BIOLOGY (Greek Words) bios – “ life “
logus – “ to study “
 science of life
 the study of living things
BRIEF HISTORY OF BIOLOGY
I. PRIMITIVE PERIOD
 characterized by uncritical accumulation of
information
 mainly derived from the practical processes or
necessities of obtaining materials like the basic needs
 accumulation of knowledge was not recorded
II. CLASSICAL PERIOD
 began with the Greeks and continued with the
Romans
 it marked by great curiosity about natural phenomena
and ability to organize biological knowledge and
record it
 HIPPOCRATES
 ARISTOTLE
 THEOPHRASTUS
 GALEN
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III. RENAISSANCE PERIOD
(14TH to 16TH centuries )
 curiosity about living things, its structure and
functions were the main concern during this time
 MICHAEL ANGELO
 ANDREAS VESALIUS
 WILLIAM HARVEY
 LEONARDO da VINCI
IV. MODERN ERA (17th century to present)
 The introduction of microscope at the beginning of
the 17th century marked the start of modern biology
 ANTON VAN LEEUWENHOEK
 ROBERT HOOKE
 ROBERT BROWN
 MATTHIAS JACOB SCHLEIDEN
 THEODORE SCHWANN
 CAROLUS LINNAEUS
 JEAN BAPTISTE LAMARCK
 CHARLES DARWIN
 LOUIS PASTEUR
 GREGOR MENDEL
 HUGO de VRIES
 E. H. STARLING
 ERNST HAECKEL
 H. E. COWLA
 V. E. SHELFORD
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BRANCHES OF BIOLOGY
I.ACCORDING TO ASPECT OR METHOD OF
STUDY:
1. Anatomy
14. Histology
2. Biogeography
15. Limnology
3. Biochemistry
16. Morphology
4. Biological Earth Science 17. Nomenclature
5. Biological Psychology
18. Ontogeny
6. Biomathematics
19. Organology
7. Biophysics
20. Oceanography
8. Cytology
21. Paleontology
9. Ecology
22. Pathology
10. Embryology
23. Phylogeny
11. Evolution
24. Physiology
12. Endocrinology
25. Systematic
Taxonomy
13. Genetics
26. Zoogeography
II.ACCORDING TO THE TYPE OF ORGANISMS
1. Bacteriology
10. Mammalogy
2. Botany
11. Microbiology
3. Carcinology
12. Mycology
4. Conchology
13. Ornithology
5. Entomology
14. Parasitology
6. Helminthology
15. Phycology
7. Herpetology
16. Protozoology
8. Ichthyology
17. Virology
9. Malacology
18. Zoology
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THE NATURE OF LIFE
LIFE – is the state of an animal or plant in which its
organs are capable of performing their
functions
CHARACTERISTICS OF LIVING THINGS AND
HOW IT DIFFERS FROM NON-LIVING
NON-LIVING
CHARACTERISTICS
LIVING THINGS
THINGS
1.ORGANIZATION
 made up of cells
 made up of
atoms
 can combine
chemical elements for  can not
their needs
recombine
materials
2.GROWTH
 internal growth
 external
(INTUSSUSCEPTION)
growth
(ACCRETION)
3.LIFE CYCLE
 definite life cycle
 no orderly
(IRREVERSIBLE)
cycle
4.REPRODUCTION
 can reproduce
sexually or asexually
 can not
reproduce
5.FORM/SIZE
 definite form/size
6.MOVEMENT
 can move by
themselves
 materials can
vary widely
 can move by
external force
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7.IRRITABILITY
 disproportionate
reaction to changes
8.ADAPTABILITY
 “autoplastic”
 “alloplastic”
9.METABOLISM
 anabolism
 catabolism
 vital processes takes
place
10.CHEMICAL
COMPOSITION
 made up of organic &  no definite
chemical
inorganic
composition
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 proportionate
reaction to
change
 can not adapt
to changes
 does not
undergo vital
processes
COMPARISON BETWEEN PLANTS and ANIMALS
POINT OF
COMPARISON
1.FORM and
SRUCTURE
2.METABOLISM
ANIMALS
PLANTS
 body form is
rather constant
 organs are
mostly internal
 cells are within
delicate
membrane
 growth is
usually
differential
 mostly with
melanin
pigment
 body form is often
variable
 “Heterotrophs”
(major
consumer)
 undergo
cellular
respiration
 end products
are CO2,H2O
& urea
 “Autotrophs”
(major producer)
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 organs are added
externally
 cells are within
thick rigid cell
walls
 growth is usually
terminal
 mostly with
chlorophyll
pigment
 undergo
photosynthesis
 O2 is released as
by product
3.IRRITABILITY
 with nervous
system
 can respond
faster to
stimuli
 without nervous
system
 respond slower to
stimuli
THE NATURE OF LIFE:
THEORIES ON THE ORIGIN OF LIFE
1. Divine Creation Theory
2. Biogenesis
3. Abiogenesis or Spontaneous Generation
4. Cozmozoic or Interplanetary
5. Naturalistic Theory
6. Philosophical Theory of Eternity
7. Big Bang Theory and Chemical Evolution
8. Coacervate Theory
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CHEMICAL BASIS OF LIFE
PROTOPLASM – the living part of the cell which is
composed of complex mixture of inorganic and organic
compounds.
MATTER – anything that occupies space and has
mass
I. PHYSICAL PROPERTIES OF MATTER
Example:
 odor
 color
 taste
 transparency
 physical states
density
boiling point
freezing point
melting point
STATES OF MATTER
1. Gases
3. Solids
2. Liquids
4. Plasma
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II. CHEMICAL PROPERTIES
Substance undergoes change in composition
Example:
 rusting (shiny bright metal) reddish
brown
 cooking egg (colorless albumin)
change to white
ATOMS
 basic building block of matter
 smallest particle/unit of an element
 composed of protons (+)
neutrons (neutral)
electrons (-)
MOLECULES – smallest particle of a compound/
element consisting of two or more atoms
ELEMENTS
 simplest form of a substance that can not be
decomposed by simple chemical means
 possess either positive or negative charge
 classified into metals, non metals & metalloids
COMPOUNDS
 substances whose molecules are made up of two
or more kinds of atoms
 classified into organic & inorganic
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CHEMICAL BONDING
 interactions involving atoms of elements
combining with one another
 classified into covalent bond, ionic bond &
hydrogen bond
I.COMPOUNDS:
A. Organic – contain carbon atoms in their molecules
FOUR IMPORTANT ORGANIC COMPOUNDS IN
THE ORGANISMS BODY
1. CARBOHYDRATES – simplest and most abundant;
main source of energy in the body
THREE CLASSES OF CARBOHYDRATES
1. starches
2. cellulose
3. sugars
a. MONOSACCHRIDES/SIMPLE SUGARS
Example:
 glucose (dextrose or blood sugar)
 fructose (fruit sugar)
 galactose (milk sugar)
 mannose
molecular formula – C6H12O6
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b. DISACCHARIDES/DOUBLE SUGARS
Example:
 sucrose (table sugar)
 lactose (milk sugar)
 maltose (malt sugar)
molecular formula – C12H22O11
c. POLYSACCHARIDES/COMPLEX
SUGARS
Example:
 starches (energy storage in plant)
 glycogen (animal starch)
 cellulose (structural materials in
plants)
2. PROTEINS – the most important organic compounds
AMINO ACIDS
 building blocks of proteins
 important for growth and repair of tissues
 act as enzymes, hormones, antigens and
antibodies
THREE TYPES OF PROTEINS
1. fibrous protein – keratin and silk
2. globular protein – hemoglobin
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3. conjugated protein – nucleoprotein ( histones ),
glycoprotein (mucin), lipoprotein (serum & brain
tissue), chromoprotein (cytochrome)
3. NUCLEIC ACIDS
 the large and the most complex organic molecules
 important for protein synthesis and heredity
POLYPEPTIDES – are the building blocks of
nucleic acids
TWO KINDS OF NUCLEIC ACIDS
1. DNA (deoxyribonucleic acid)
found inside the nucleus of cell
2. RNA (ribonucleic acid)
found both inside and outside the nucleus of
the cell
4. LIPIDS
 are fats and other related substances
 insoluble in water
 soluble only in chloroform and acetone
GLYCEROL and FATTY ACIDS
 are the building blocks of lipids
 important in the storage of energy and component
of the cell membrane
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TYPES OF LIPIDS
a. Simple Lipids – oils, fats, waxes
b. Compound/Complex lipids – steroids, cholesterol
and phospholipids
B. Inorganic Molecules
 usually do not have carbon atoms
 often associated with non living things
THE MOST COMMON INORGANIC
MOLECULES FOUND IN AN ORGANISMS BODY
1. WATER
 most abundant component of the protoplasm (60 –
90%)
 universal solvent
 retain heat well
 high surface tension
2. GASES (oxygen and carbon dioxide)
 importance in the organism’s body
a. respiratory gases
b. in tissue fluids (blood & lymph)
c. in oxidation of food molecules in order to release
energy
3. MINERALS
4. ORGANIC SALTS
present in the bone, teeth
and shells
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Examples:
 calcium carbonate - CaCO3
 calcium phosphate - ( Ca3( PO 4 ) 2 )
 sodium chloride - NaCl
Important in Vital Processes such as:
a. irritability of muscles and nerves
b. growth and repair of tissues
c. act as buffers or regulators of acid-base balance
VITAMINS
 Inorganic compounds usually of plant origin
 Accessory food factors needed by man and
animals for normal growth and development
BASIC FOOD GROUPS:
The Basic Seven Food Groups Based on their Nutrient
Contents
GROUP I - meat, poultry, fish, eggs, dried beans, peas
and nuts
GROUP II - green and yellow leafy vegetables
GROUP III- citrus fruits, raw cabbage, salads greens and
tomatoes
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GROUP IV- potatoes, other vegetables and non-citrus
fruits
GROUP V - bread, breakfast cereals, flour biscuits and
crackers
GROUP VI - butter and fortified margarine
GROUP VII- milk and milk products
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THE CELLULAR BASIS OF LIFE
CELL (CYTOLOGY)
 the basic structural and functional unit of all living
things
 varies in shape and size
BRIEF HISTORY OF CELL BIOLOGY
1. ROBERT HOOKE (1665) - cells
2. ANTON VAN LEEWENHOEK (1674) - protozoan,
red blood cells, capillary system
3. ROBERT BROWN (1833) - nucleus
4. DUJARDIN (1835) - protoplasm
5. MATTHIAS SCHLEIDEN (1838)
6. THEODOR SCHWANN (1839) - all living things are
composed of cells
7. RUDOLF VIRCHOW (1858) - all cells come from
pre-existing cells
CELL THEORY
1. All organisms are made up of cells and a cell is the
structural and functional unit of organisms.
2. Cells are capable of self-reproduction and cells come
only from pre-existing cells.
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TYPES OF CELLS
PROKARYOTIC CELLS
EUKARYOTIC CELLS
 cells without true nucleus  cells with true nucleus
 cell size ranging from 1 to  ranging from 10-100um
10 um in linear dimension
 outer boundary is
 composed of plasma
composed of cell wall &
membrane made up of
plasma membrane
phospholipids bilayer of
proteins
 no membrane bounded
 with membrane nucleus
nucleus (not distinct)with
composed of multiple
nucleoid containing single chromatin
chromosome(DNA only)
 cytoplasm contains few
 contains many organelles
organelles like ribosomes,
thyllakoids, enzymes
 undergo aerobic &
 aerobic respiration only
anaerobic respiration
 divide by binary fission
 by mitosis/meiosis
 mostly unicellular
 mostly multicellular
 ex.bacteria, cyanobacteria  ex. Animals, plants, protest,
or blue green algae
fungi
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MORPHOLOGY and PHYSIOLOGY OF
EUKARYOTIC CELL
STRUCTURES CHARACTERISTICS FUNCTIONS
1.Cell Membrane/  outermost membrane  give strength,
Plasma
of the cell
shape and
Membrane
protection to
the cell
 with cilia,
flagella
 microvilli
 pinocytic
vesicles
2.Protoplasm
 triple layered
composed of protein
& lipids
3.Nucleus
consist of:
 the most distinct
structure located at
the center of the cell
 the control
center of the
cell
 important in
cellular
reproduction
a. nuclear
membrane
 encloses the nucleus
 protects and
regulates the
 regulates
traffic flow
of materials
 jelly-like living
 exhibit the
substance of the cell
properties
comprising the
and activities
nucleus & cytoplasm
of life
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passage of
materials
b. nucleoplasm
 the cytoplasm inside
the nucleus
 chromosomes
and nucleoli
are
suspended on
it
c. chromosomes
 thread like bodies
that bear the genes
 important in
heredity
d. nucleolus
 dark staining bodies
inside the nucleus
 for protein
synthesis
4.Cytoplasm
 the protoplasm
outside the nucleus
contains organelles
and inclusions
 serve to carry
out the
direction of
the nucleus
ORGANELLES  permanent,
subcellular structure
in the cytoplasm
 performed
the different
metabolic
activities of
the cell
A. Endoplasmic
Reticulum
 routes of
 system of membrane
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enclosed canals
forming network in
the cytoplasm
TYPES:
 Smooth ER
 Rough ER
b.Ribosomes
transport for
the different
materials
within the
cells
 without ribosomes
 with ribosomes
 for protein
 spherical bodies
synthesis
aggregates of protein
and RNA
C.Golgi Complex  system of membrane  secretes
chemical
enclosed vesicles
products,
membrane
repair,
transport of
materials,
packaging
secretory
products
D. Mitochondria  rounded cylinders or  powerhouse
of the cell
globules
E. Lysosomes
 act as the
 contains powerful
“suicide bag of
digestive
hydrolytic enzymes
the cell”
system of the
cell
F. Plastids
 gives color to
 mostly found in
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plants
 colored substances
within the cells
KINDS:
 chromoplast
 leucoplast
G.Centrosomes
H.Vacuoles
KINDS:
 food vacuoles
 water
vacuoles
 colored plastids
 contained
chlorophyll(green)
 colorless plastids or
white
 small dark bodies
located above the
nucleus contains one
or two centrioles
 membrane enclosed
cavities filled with
fluid or granular
materials
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the
organisms
 contained
pigments and
other
materials
 play a role in
spindle
formation
during cell
division
 for the
storage of
food and
water
DIFFERENCES BETWEEN PLANT and ANIMAL
CELL





PLANT CELL
bounded by cell wall
and plasma
membrane, containing
cellulose and other
compounds
contained plastids
lack lysosomes
have large vacuoles
for the storage of H2O
undergo
photosynthesis
ANIMAL CELL
 bounded by plasma
membrane only, no
cell wall
 lack plastids
 contained lysosomes
 small vacuoles for the
storage of food
 undergo digestion
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CELLULAR REPRODUCTION / CELL DIVISION
 process exhibit by all living organisms as they grow or
increase in size and number of the cell
TYPES:
1. MITOSIS (duplication division )
 process that produces two daughter cells with the
same quantity and quality of chromosomes as the
parent cell (diploid)
 involve the division of…
 nucleus (karyokinesis)
 cytoplasm (cytokinesis)
 occur in the somatic cell (body cells) of eukaryotic
organism
2. AMITOSIS (direct cell division)
 process of division but there is no evidence of mitotic
changes
 the nucleus and cytoplasm simply divide unequally or
roughly equal without undergoing the phases of
mitosis
 cells do not function normally
 occur in prokaryotic organism or in degenerating cells
under pathological conditions
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3. MEIOSIS (reduction division)
 process that produces four daughter cells with haploid
no. of chromosomes as the parent cell
 involves two successive divisions mitosis 1 and
meiosis 2
 occur in sex cells (egg and sperms)
CELL CYCLE:
 the cyclical process of growth and mitosis
 consists of 4 phases, the 3 stages of interphase (G1, S
and G2)) and the mitotic phase
INTERPHASE
 the preparatory stage for the cell to undergo mitosis
 consists of 3 subdivisions , the
 G1 period (pre synthesis interphase)
 S period (synthesis phase)
 G2 period (post synthesis interphase)
MITOTIC PHASE (consists of 4 phases)
1. PROPHASE
 the stage of preparation
 the chromosomes appear much shorter but thicker and
start to coil tightly
 centrioles become visible and move to the opposite
poles of the nucleus
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 nucleolus no longer visible
 nuclear membrane start to disappear
 mitotic apparatus formed (asters, spindles fibers)
2. METAPHASE
 the stage of separation
 chromosomes migrate and align at the equatorial plane
(center)
 centromeres of each chromosomes are attached to the
spindle fibers
3. ANAPHASE
 the stage of migration
 centromeres of each chromosomes divide or split
 each chromatid of a double stranded chromosome
separates from its sister chromatid and goes to the
opposite poles
 cytokinesis begins (formation of cell plate in the plant
cell and cleavage furrow in animal cell)
4. TELOPHASE
 stage of nuclear reconstruction
 two sets of chromatids reached the opposite poles
 chromosomes start to uncoil, becomes longer, thinner
and less distinct
 nuclear membrane starts to reappear enclosing each of
chromosomes
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 nucleolus also reappear while mitotic apparatus
disappear
 cytokinesis completed resulting into two daughter
cells with the same quantity and quality of
chromosomes as the parent cell
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TISSUES
 composed of cells with similar structures and
functions
PLANT TISSUES
I. MERISTEMATIC TISSUE
 cells capable of active cell division (mitosis)
A. TERMINAL / APICAL MERISTEMS
 located at the tips of roots and stems
 responsible for the increase in length of the plant
B. INTERCALARY MERISTEMS
 portion of the apical meristems separated from the
apex during development
 lie below the node and the base of stem of grasses
C. LATERAL MERISTEMS
 located in the periphery of the roots and stems
 responsible for the increase in the diameter of the
organ
II. PERMANENT TISSUE
 composed of mature, differentiated cells
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A. SURFACE TISSUE
 form the protective outer covering of the plant
Example:
Epidermis
 short – lived in many plants
 replaced by periderm tissue when the plants grow or
becomes matured (outer bark of old trees)
B. FUNDAMENTAL TISSUE
 simple tissues composed of a single type cell
 form the bulk of the softer parts of plants
 responsible for storage, basic metabolism and support
TYPES:
1. PARENCHYMA (most abundant plant tissue)
 cells usually have thin primary walls, no secondary
walls
 with large vacuoles
chlorenchyma – parenchyma with chloroplast
function for photosynthesis
aerenchyma – parenchyma with intercellular
spaces to improve gas exchange
 both found in leaves, also in stems and roots
2. COLLENCHYMA
 composed of elongated cells
 cell walls are irregularly thickened
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 important supporting tissue in young plants, in the
stem of non-woody older plants and in leaves (petiole)
3. SCLERENCHYMA
 composed of rigid cells, uniformly thick
 with heavily lignified secondary walls
 occur in all mature parts of the plants
 support the non-extending regions of plants
TYPES:
 SCLEREIDS- short cells with variable shapes
 FIBERS- long, slender cells
4. ENDODERMIS
 a layer surrounding the vascular tissue core of roots
and stems
 appear like elongated parenchyma cells with lignified
and suberized band called “casparian strip”
C. VASCULAR TISSUE / CONDUCTIVE TISSUE
 Composed of several kinds of cells that differ in
structure and in function
 Specialized for long distance transport of water and
dissolved solutes (nutrients)
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TYPES:
1. XYLEM
 Responsible for the transport of water and dissolved
substances upward in the plant body
2. PHLOEM
 Responsible for the transport of food / nutrients both
up and down in the plant body
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ANIMAL TISSUES
I. EPITHELIAL TISSUE
 covering of external surface or lining of all free body
surfaces (internal)
 forms continuous layer of compactly arranged cells
Functions: mainly for covering and protection
TYPES AS TO SHAPE OF THE CELLS:
1. SQUAMOUS EPITHELIUM
 made up of thin, flat cells that resemble blocks
Location: outermost layer of the skin, lining of mouth,
esophagus
2. CUBOIDAL EPITHELIUM
 cube shaped cells in appearance
Location: lining of ducts, thyroid gland and kidney
tubules
3. COLUMNAR EPITHELIUM
 rectangular shaped cells
Location: lining of the trachea, stomach, small
Intestine
4. CILIATED/ FLAGELLATED EPITHELIUM
 maybe columnar or cuboidal cells w/c are provided
with cilia or flagellum
Location: innermost lining of the trachea, intestine,
spermducts oviduct
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TYPES AS TO STRUCTURE/NO. OF CELLS
1. SIMPLE EPITHELIAL TISSUE
 one layer of cells
2. STRATIFIED EPITHELIAL TISSUE
 two or more layers
3. PSEUDOSTRATIFIED EPITHELIAL TISSUE
 all cells are in contact with the basement membrane
but not all reach the surface
AS TO FUNCTION:
1. GLANDULAR EPITHELIAL TISSUE
 for secretion
2. SENSORY EPITHELIAL TISSUE
 for reception of stimuli and transmission of impulses
3. GERMINAL EPITHEIAL TISSUE
 for reproduction
4. PROTECTIVE EPITHELIAL TISSUE
 for protection, covering
II. CONNECTIVE TISSUE/ SUPPORTIVE
 cells are far apart, very variable embedded in
intercellular matrix (liquid, semi-solid, solid)
 contains large amount of cementing substance
between cells
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Functions:
 binds structure together
 connects many body parts
 fill spaces, store fats and forms blood cell
 provides support and protection
Types as to Arrangement of Fibers in the Matrix:
1. Loose connective tissue
 loose arrangement of fibers in the matrix
 cells (fibroblasts) are farther apart separated by
jelly-like matrix with white collagen fibers (for
flexibility and strength) and yellow elastic fibers (for
elasticity)
 lies beneath the epithelium of the skin and most of
the internal organs
a. mesenchyme
b. mucous connective tissue
c. reticular connective tissue
d. areolar connective tissue
e. adipose connective tissue
2. Dense (fibrous) connective tissue
 contains many collagen fibers that are packed
closely together
 more specific functions in vertebrates than loose
connective tissue
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 with less amorphous ground substance
a. irregular arranged dense connective tissue
b. regular arranged dense connective tissue
3. Specialized connective tissue
a. cartilages
 skeleton during embryonic stage; composed of cells
(chondrocytes) located in small spaces called
“lacunae with collagenous or elastic fibers”
Types as to appearance of the matrix:
 hyaline cartilage
 elastic cartilage
 fibrocartilage
b. bones or osseous tissues
 rigid form of connective tissue
 comprises most of the skeleton in higher vertebrates
 composed of cells (osteocytes) located in small
cavities (lacunae) of calcified matrix
 radiating from each lacuna are narrow channels
(canaliculi) which penetrate adjacent canaliculi of
neighboring lacunae forming lamellar structure
c. hemopoietic tissue
 formation and maturation of blood cells
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d. blood
 composed of blood cells (erythrocytes, leukocytes,
and thrombocytes) and a fluid intercellular
substance (plasma)
III. MUSCULAR TISSUE
 cells are usually elongated and are bound together
into sheets or bundle by connective tissue
 muscle cells have greater capacity for contraction
than most other cells
 responsible for most movement in higher animals
TYPES AS TO STRUCTURE/ FUNCTION:
a. Skeletal/ Striated Muscle
 composed of long, cylindrical filamentous cell
 found attached to the skeleton
 responsible for voluntary movement of the body
b. Cardiac/ Striated Muscle
 composed of linear, branching bundles of fibers
joined end to end by intercalated disc
 found in the walls of the heart
 responsible for the involuntary contraction of the
organ
c. Smooth/ Unstriated Muscle
 also called visceral muscle
 composed of elongated cells with tapered ends
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 spindle shaped or fusiform
 found in the internal organs (stomach,intestine)
 responsible for the involuntary movement of these
organs
IV. NERVOUS TISSUE
 composed of nerve cells or neurons
 has great capacity to respond to stimuli since they
can be easily stimulated and can transmit impulses
rapidly
NEURONS
 Made up of cell body ( perikaryon ) and one or
more protoplasmic processes (axon and dendrites)
 Do not undergo cell division
 Responsible for reception of stimuli and
transmission of impulses
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THE PLANT AS AN ORGANISM
The plant is a diverse group of organisms. Its members
range from simple unicellular and multicellular algae to
highly developed vascular plants. It is divided into
categories based upon the structure and reproduction
methods.
Of all the members of the plant kingdom, the vascular
plants show the greatest internal specialization into tissues
and organs. It is considered as the dominant plant group on
land today.
MAJOR GROUPS OF VASCULAR PLANTS:
1. SPORE – BEARING
 those that produces spore instead of seed
an asexual reproductive cell that develops into a
new plant
Example: ferns, club mosses, horse tails
2. GYMNOSPERMS
 group of seed producing plants in which the seeds are
naked or not protected by a case, “ovary wall”
 it may or may not produce CONES
a fruiting structure composed of modified leaves or
branches
37
Example: CYCADS – look like a short palm tree
GINKGOS – large tree with fan shaped leaves
CONIFERS or CONE BEARERS – pine tree,
junifers, red wood
3. ANGIOSPERMS (flowering plants)
 the largest group among vascular plants
 group of seed producing plants in which the seeds are
enclosed or protected by an ovary wall (fruits)
 its unique and outstanding structure is the FLOWER
Example: all the crop plants in orchards, garden and
fields from tiny herbs, shrubs to trees
TWO MAJOR SUBCLASSES:
A. MONOCOTYLEDONS (monocot)
Example: grasses, rice, corn, lilies, orchids and other
grass like plants
B. DICOTYLEDONS (dicot)
Example: roses, sunflowers, citrus plants, maple trees
And other great variety of plants
38
STRUCTURAL DIFFERENCES BETWEEN THE
TWO
MORPHOLOGICAL
MONOCOT
STRUCTURE
1. Cotyledons/Embryo  1 cotyledon
trimerous
2. Flowers/Petals
 MULTIPLE OF
3’s
3. Leaves/Venation
 Parallel- Veined
4. Roots
 Fibrous/Diffuse
5. Stem Anatomy
 Scattered
Vascular
Bundles
 Numerous
 Without
Vascular
Cambium
DICOT
 2 cotyledons
pentamerous
 MULTIPLE
OF 5’s
 Net – Veined
 Tap Root
 Vascualr
Bundles in
Rings
 Few
 With vascular
Cambium
TYPICAL ORGANS OF FLOWERING PLANTS:
A. VEGETATIVE ORGANS – root, stem, leaves
 for growth, development and maintenance of life
B. REPRODUCTIVE ORGANS – flowers, fruit, seeds
 concerned with sexual reproduction and production of
seeds
39
ORGANS
 composed of several tissues grouped together into
structural and functional unit
PLANT ORGANS
I. SHOOT SYSTEM – visible structure above the ground
portion (aerial)
A. STEM
 ascending axis of the plant on which the leaves and
buds are attached
 consist of nodes and internodes
Function: for support, conduction, and storage of
food and water substances
TYPES OF STEM:
HERBACEOUS
WOODY –
B. LEAVES
 lateral outgrowth of the stem
 usually flat, thin, expanded and green in color
 cutinized and with chlorophyll
Function: site for the process of PHOTOSYNTHESIS,
RESPIRATION and TRANSPIRATION
40
TYPES OF LEAVES:
SEED LEAF
FOLIAGE LEAF
C. FLOWERS
 reproductive organ of the plant
 usually with colored petals and contain pigments
 male germ cell from the STAMEN unite with the
female germ cell from PISTIL, an embryo is formed.
Function: concerned with the production of seeds and
fruits
D. FRUITS
 matured or ripened ovary of the flower
 contain the seeds which carry the embryo
Function: help in the dispersal of seeds to distant places;
hold and protect the seeds
E. SEEDS
 fertilized and developed ovules
 contain the embryo
Function: responsible for the development of new species
II. ROOT SYSTEM – structure beneath the ground
portion, usually subterranean, no chlorophyll and
uncutinized
Function: root for ANCHORAGE and ABSORPTION of
food and water substances
41
TYPES OF ROOT:
TAP ROOT
FIBROUS/DIFFUSE
ADVENTITIOUS
ORGANS
1. ROOT
2. STEM


3. LEAVES

4. FLOWER

5. FRUITS

6. SEEDS

STRUCTURES/PARTS
primary root, secondary root
nodes, internodes, lenticles,
buds, leaf scar
blades/lamina (margin, midrib
veins)petiole, stipule
stamen (anther, filament)
pistil (stigma, style, ovary)
petals, sepals, peduncle,
receptacle
pericarp (exocarp, messocarp,
endocarp)
placenta, locule, seeds
seed coat (testa, tegmen)
cotyledon
42
ANIMAL ORGANS
1. SKIN (INTEGUMENT) - outermost covering of the
body surface
Function:
 protection
 sensation
 respiration
 absorption
 regulation of body temperature
2. STOMACH – the largest and highly muscular part of
the digestive tube
Function:
 temporary storage of food
 partial digestion of food
3. SMALL INTESTINE – the longest and most coiled
part of the digestive tube
Function:
 site of final/complete digestion and absorption of
food
4. HEART – highly muscular pumping organ of the body
Function:
 pumps blood to all parts of the body
43
5. BLOOD VESSELS – closed tube that serves for the
passageway of blood
Function:
 for the passageway of blood (artery, vein, capillary)
6. LUNGS – spongy paired organs
Function:
 for gaseous exchange/respiration
7. KIDNEYS – paired bean shaped excretory organs of the
body
Function:
 eliminates nitrogenous wastes of the body by
filtering the blood
8. LIVER – the largest gland in the body
Function:
 secretes bile (emulsifier of fats)
9. REPRODUCTIVE ORGANS
A. OVARIES – female sex organs that produces and
secretes egg cells (ova) and hormones (estrogen,
progesterone)
B. TESTES – male sex organ that produces or
secretes sperm cells and male hormones
(testosterone)
44
10. BRAIN – most specialized organ of the body located
in the cranial cavity of the skull (master organ)
Function:
 the coordinator and the director of conscious and
unconscious activities (center of communications)
45
ORGAN SYSTEM
 group of organs that work together in the
performance of a specific function
THE TEN ORGAN SYSTEMS OF VERTEBRATE
ANIMALS and THEIR PRINCIPAL FUNCTIONS
1. INTEGUMENTARY SYSTEM
 body covering and protection from the environment
2. MUSCULAR SYSTEM
 movement and locomotion
3. SKELETAL SYSTEM
 support and framework of the body
4. DIGESTIVE SYSTEM
 converting insoluble food to soluble or absorbable
forms; egestion of wastes
5. RESPIRATORY SYSTEM
 exchange of gases (carbon dioxide and oxygen)
6. CIRCULATORY SYSTEM
 transportation of different materials or substances
7. REPRODUCTIVE SYSTEM
 production of new individuals of the same kind
8. EXCRETORY SYSTEM
 elimination/disposal of nitrogenous wastes of
metabolism
46
9. NERVOUS SYSTEM
 reception of stimuli; transmission of impulses and
coordination of functions
10. ENDOCRINE SYSTEM
 regulation of internal processes and adjustment to
external environment
47
INTEGUMENTARY SYSTEM
Functions:
 covering and protection
 secretions of substances
 excretion of metabolic wastes
 sensation
 respiration
 regulation of temperature
 storage of reserve food
 nourishment for the young
THE SKIN (INTEGUMENT)
 largest organ of the vertebrate’s body
 covers the surface of the body
 consists of three layers; (1) outer epidermis (2) inner
dermis (3) subcutaneous layer
LAYERS OF THE SKIN:
1. EPIDERMIS (outer, thinner)
 made up of stratified squamous layer of epithelial
tissue
 a layer of dead cells that usually shed as thin flakes
(keratinized)
 composed of “melanin” pigments
 with epidermal derivatives/structures like hair, nail,
claw, hoof, horn, antler
 divided into five specific layers (mammals)
48
a. stratum corneum
b. stratum lucidum
c. stratum granulosum
d. stratum spinosum
e. stratum germinativum
2. DERMIS (inner, thicker)
 made up of fibrous connective tissue containing
collagen and elastic fibers
 contains muscle fibers, glands, pigment cells, blood
vessels, hair follicle and sensory nerves
 provides structural support for the epidermis and act
as matrix for many nerve endings, muscles and
specialized cells
 consists of two regions
a. papillary regions
b. reticular regions
SKIN GLANDS:
A. SWEAT GLANDS
 give off small amount of liquid waste matter
B.OIL GLANDS OR SEBACEOUS GLANDS
 give off oily substances that make the hair smooth and
glossy (sebum)
 prevents the skin from dryness
C. MUCOUS GLAND
 give off slippery substance due to mucin
49
3. SUBCUTANEOUS LAYER (innermost)
 composed of fat – rich cells (adipose tissue) that
serves for the storage of fats
 act as shock absorbers
 provides insulation to conserve body heat
COMMON SKIN DISORDERS:
 acne
 eczema
 tinea flave (an-an)
 prickly heat (bungang araw)
 sunburn
 athlete’s foot
 boil
 contact dermatitis
 scabies
50
SKELETAL SYSTEM
Functions:
 support the body
 attachment of muscles
 protection of internal organs
 act as levers for locomotion
 production of blood cells
 give stability and shape to the body/frame work
 stores the elements sodium, calcium, and potassium,
then releases to the blood
 holds the reserves protein that the body uses during
fasting
SKELETON
 the framework of the animals body composed of
cartilage, bone or a combination of both
CARTILAGE – white, soft, rubbery tissues
BONE – opaque, hard, compact tissues
TYPES OF SKELETON:
I. AS TO FORMATION
MEMBRANE OR DERMAL BONE
 Formed by direct OSSIFICATION (bone)
ENDOCHONDRAL OR CARTILAGE BONE
 Formed by replacement of pre – existing cartilage
into a bone
CHONDRIFICATION
OSSIFICATION
51
II. AS TO KIND OF BONE TISSUE
 spongy bone
 compact bone
III. AS TO LOCATION
EXOSKELETON or Dermal Skeleton
 build up outside the body
 formed from a secretion called CHITIN
Example: Arthropods
ENDOSKELETON
 build up inside the body surrounded by soft tissue
 divided into AXIAL and APPENDICULAR skeletons
Example: vertebrates
AXIAL REGION – forms the main axis of the body
 composed of the vertebral column, ribs, sternum and
skull
1. VERTEBRAL COLUMN/ BACKBONE (26)
 the main axial support of vertebrates
 a chain of bones that runs down the middle of your
back
 protects the SPINAL CORD
2. RIBS (12 Pairs or 24)
 series of cartilaginous or elongated bony structures
attached to the vertebrae
 forms the THORACIC CAGE involved in breathing
 protects the heart and lungs
52
Types of Ribs
a. TRUE RIBS – the first 7 pairs
b. FALSE RIBS – the next 3 pairs
c. FLOATING RIBS – the last 2 pairs
3. STERNUM / BREAST BONE (1)
 flat narrow structure that serve as ventral attachment
of the ribs in mammals
 strengthen the anterior part of the trunk
4. SKULL (29)
 the framework of the head
 includes the bones of the cranium (brain box), sense
capsule (nose, ear, eye) and visceral arches (jaw,
hyoid, larynx)
 encloses and protects the brain as well as the sense
organs
APPENDICULAR REGION – endoskeletal structures
which are located laterally or at the side of the body
 composed of the pectoral girdle (shoulder), pelvic
girdle (hip), bones of the forelimbs or (arm), and the
bones of the hind limbs or (legs)
53
UPPER EXTREMITIES: (64)
1. PECTORAL GIRDLE
2. FORELIMBS
- scapula
- humerus
- coracoid
- radius & ulna
- clavicle
- carpals
- metacarpals
- phalanges
LOWER EXTREMITIES: (62)
3. PELVIC GIRDLE
4. HINDLIMBS
- ilium
- femur
- ischium
- tibia & fibula
- pubis
- patella
- tarsals
- metatarsals
- phalanges
Distribution of Bones in Human:
New Born Baby - 350 bones
Adult Human
- 206 bones
I. AXIAL REGION – 80 bones
 cranium ………….8
 face………………14
 ears……………….6
 hyoid……………...1
 sternum…………...1
 vertebral column…26
 ribs………………24
54
II. APPENDICULAR REGION – 126 bones
 pectoral girdle and forelimbs………………64
 pelvic girdle and hindlimbs………………..62
JOINTS – (SYNDESMOLOGY)
 articulations between cartilages or bones
LIGAMENTS – connective tissue that connects bone
to bone
GENERAL TYPES OF JOINTS:
1. SYNARTHROSES – are immovable joints
Example: sutures of the skull
2. AMPHIARTHROSES – slightly movable joints
Example: intervertebral disk
(in between vertebrae – sacrum & ilium)
3. DIARTHROSES – freely movable joints
- most common joints in the body
TYPES:
a. Gliding Joint / Arthrodia
ex. wrist, ankle
b. Hinge Joint / Ginglymus
ex. elbow, knee
c. Ball and Socket / Enarthrosis
ex. shoulder, hips
d. Pivot Joint / Diarthroses Rotatoria
ex. joint between the atlas and axis of the vertebral
column (neck)
55
COMMON DISORDERS OF THE BONE:
 dislocation
 sprain
 fracture
 rickets
 osteoporosis
 scoliosis
 bursitis
56
MUSCULAR SYSTEM (MYOLOGY)
Functions:
 for movement ad locomotion
 give shape and form to the body
 produce heat for the body (thermoregulation)
MUSCLE STRUCTURES:
1. Muscle cells are long, elongated, slender structure
called MUSCLE FIBERS which are covered by a
delicate membrane called SARCOLEMMA.
2. Each muscle fiber is subdivided into smaller cylinders
called MYOFIBRILS.
3. The myofibril is composed of SARCOMERES attached
end to end.
4. Within each sarcomere are alternating thin and thick
myofilaments of ACTIN and MYOSIN proteins.
5. The entire muscles are surrounded by an external
connective tissue wrapping called the EPIMYSIUM or
FASCIA.
6. Each muscle bundle is further enclosed by a connective
tissue layer called the PERIMYSIUM.
7. Four or more muscle fibers are in turn enclosed the
ENDOMYSIUM.
MUSCLES ARE ATTACHED TO THE BONES BY A
TOUGH FLEXIBLE TISSUE CALLED TENDONS
57
TYPES OF MUSCLES: (AS TO STRUCTURE)
BASIS OF
SKELETAL
SMOOTH
CARDIAC
COMPARISON MUSCLE
MUSCLE
MUSCLE
1.Location
 attached to  wall of the  walls of the
the skeleton
stomach &
heart
intestine
2. Shape of the  elongated or  spindle elongated
fibers
filamentous
shaped or
fibers that
fusiform
branch
 striated
 unstriated
 striated
3. Number of
 many per
 one per
 one per
nuclei
muscle cell
muscle or
muscle cell
or
uninucleated
but appears
multinucleat
to be many
ed
4. Position of
 peripheral
 central
 central
nuclei
 present
 absent
 present
5. Cross
(dark &
striations
light)alterati
on
 most rapid  slowest
 intermediat
6. Speed of
e
contraction
 voluntary
 involuntary  involuntary
7. Type of
- controlled by - cannot be
- controlled
nervous control
the will
controlled
by the will
58
AS TO ACTION:
Agonist or prime mover – principal mover for specific
action.
1. Antagonist – for opposite movement
2. Synergist – helps to stabilize movement of one joint
3. Fixator – fixes the position of the limb when the
movement is occurring
AS TO SPECIFIC FUNCTION:
1. FLEXORS
7. ELEVATORS/
LEVATORS
8. DEPRESSORS
9. CONSTRICTORS
10.DILATORS
11.SPHINCTERS
2. EXTENSORS
3. ADDUCTORS
4. ABDUCTORS
5. PRONATORS
HOW THE MUSCLE WORKS:
 Skeletal muscles must be stimulated by nerves to
operate.
 Smooth muscles must be stimulated by hormones and
a special set of nerves that belong to the autonomic
nervous system
According to the SLIDING FILAMENT THEORY,
muscle cells are made up of long parallel chains of protein
molecules that can slide over each other. If the muscle cell
59
is stimulated, the molecular chains slide over one another
and the cell contracts.
All muscle fibers produce wastes called LACTIC ACID
as they work. If a muscle work very hard, these wastes
collect in the muscle and lead to MUSCLE FATIGUE or
inability of the muscles to contract due to accumulation of
lactic acid and the depleton of ATP.
COMMON DISORDERS OF MUSCLE:
 RHEUMATISM
 ARTHRITIS
 GOUT
 MUSCLE CRAMPS
 MUSCULAR ATROPHY
 MUSCLE BRUISE
60
DIGESTIVE SYSTEM
Functions:
 ingestion of food
 digestion or breaking down of complex substances
(food) into simple forms (nutrient)
 absorption of digested food
 egestion or excretion of undigested food
TYPES OF DIGESTION:
As to Action
1. Mechanical Digestion – food is converted into small
pieces by physical means such as mastication by teeth
2. Chemical Digestion – food is converted into simpler
forms by the action of enzymes
As to Location
1. Intracellular – digestion takes place within the cell
particularly in the lysosomes
Example: unicellular organisms – amoeba,
paramecium
2. Intercellular or Extracellular – digestion takes place
Outside the cell; inside the digestive tube
Example: multicellular organisms/ vertebrates
61
COMPOSITION OF EXTRACELLULAR DIGESTION
1. Digestive Tube/ Alimentary Canal
 start from the MOUTH and end in ANUS
2. Digestive Glands
 organs that secrete juices containing enzymes for the
digestion of food
3. Accessory Parts
 includes structures that help in the digestion of food
Example: tongue and teeth
THE DIGESTIVE TUBE:
1. ORAL/ BUCCAL CAVITY (mouth)
a. Teeth – used for mastification of food
External parts:
 crown
 root
 neck
Internal parts:
 enamel
 dentine
 pulp cavity
 cementum
TYPES AS TO STRUCTURE/FUNCTION
 incisors
 canines
62
 premolars
 molars
TYPES AS TO APPEARANCE
 primary / milk teeth (20)
 permanent teeth (32)
b. Tongue – for tasting, manipulation, aid in swallowing
the food
c. Oral Glands – secrete mucus/ saliva for the lubrication
of food
d. Palate – roof of the mouth
2. PHARYNX/ THROAT
 common passageway of food and air
3. ESOPHAGUS
 pathway for the passageway of food
 exhibit peristalsis movement
4. STOMACH
 the largest and highly muscular part of the digestive
tube (pouch-like)
 lined with numerous folds called RUGAE
 maximum capacity 2.5 pints or more
 food can stays for about 3-5 hours
 function for temporary storage and partial digestion of
food “CHYME” thick semi fluid mass
63
The parts or division of stomach :
a. cardiac sphincter (anterior opening)
b. fundus (body)
c. pyloric sphincter (posterior end)
5. SMALL INTESTINE
 the longest and most coiled part
 lined with numerous folds called VILLI
 about 22 ft. long and food stays around 4-5 hrs.
 function for final digestion and absorption of food
The parts/ divisions of small intestine:
a. duodenum – anterior
b. jejunum – middle
c. ileum – posterior end
6. LARGE INTESTINE
 posterior part of the digestive tube
 joined to the small intestine by the ileocolic junction
(VERMIFORM APPENDIX)
 food stays for about 5 to 25 hrs. or more
 function for the temporary storage of undigested food
and further absorption of water and minerals before
the waste materials are excreted
The parts/divisions are:
a. caecum – anterior
64
b. colon – middle part divided into ascending colon,
transverse colon and descending colon
c. rectum – posterior
7. ANUS
 posterior opening of the digestive tube
 exit of fecal matter regulated by anal sphincter muscle
THE DIGESTIVE GLANDS:
1. SALIVARY GLANDS
 Secrete saliva for lubrication of food found in the
oral cavity
Types:
a. parotid – saliva with PTYALIN enzymes
b. submaxillary
c. sublingual
2. MUCUOS GLANDS
 secrete mucin for lubrication of food found in
oral cavity, esophagus, small and large intestines
3. GASTRIC GLANDS
 secrete gastric juice found in the rugae of
stomach
 composition of gastric juice are…
a. mucin
d. lipase
b. HCL
e. rennin
c. pepsin
65
4. INTESTINAL GLANDS
 secrete intestinal juice found in the VILLI of
small intestine
 composed of enzymes
a. mucin
e. sucrase
b. trypsin
f. maltase
c. amylase
g. lactase
d. lipase
5. PANCREAS
 secrete pancreatic juice that contains…
a. amylase
b. lipase
c. trypsin
6. LIVER
 largest gland of the body that secretes BILE which is
stored in the GALL BLADDER
BILE – emulsifies fat into fat globules
Other functions:
 detoxify nitrogenous wastes
 production of FIBRINOGEN
 center for fat and carbohydrate
metabolism
COMMON DISORDERS/ DISEASES:
1. peptic/ gastric ulcer
5. appendicitis
2. indigestion
6. mumps
3. constipation
7. tooth decay
4. diarrhea
66
CIRCULATORY SYSTEM
Functions:
 transport the oxygen and carbon dioxide, soluble food
materials, organic wastes, and hormones
 regulation of the pH of tissues
 protection of the body against invading microbes
 regulation of body temperature in warm – blooded
animals
TYPES OF CIRCULATION
Open-type
 well-developed blood vessels passing from the heart
to the tissues where it opens into spaces called lacunae
 from these spaces blood returns to the heart through
body spaces called hemocoel
 comes in direct contact with the tissue cells
Closed-typed
 blood is confined inside tubes or blood vessels
 blood passes from the heart to the tissue and back
through these vessels
Divisions of closed-typed circulatory system
1. blood vascular system – includes the blood,
heart, and blood vessels
2. lymphatic system – includes the lymph or
tissue fluid, and lymph vessels
67
THE BLOOD
 a specialized connective tissue
 the main transporting medium of the body
 8% of total body weight (4 to 6 liters in average adult)
 considered to be the “essence of life”
Composition of Blood
Plasma
 fluid portion of the blood
 55% of total blood volume
 90 – 92% water, 7-8% plasma proteins, and 1-2%
salts and other components
 average pH of 7.4
Formed elements
 include the cells (erythrocytes and leukocytes)
and cell fragments (thrombocytes)
 45% of total blood volume
 95% RBC; 5 % WBC and platelets
Erythrocytes
 red blood corpuscles (RBC)
 small, biconcave disks with polysaccharides on the
outer membrane
 almost the entire interior is packed with hemoglobin
68
 about 4-6 million cells per mm3, and each one of these
cells contains about 200 million hemoglobin
molecules
 hemoglobin contains 4 globin protein chains each
associated with heme, an iron containing group, iron
combines loosely with oxygen, and this way oxygen is
carried in the blood
 responsible in the transport of oxygen to body tissues
 in mammals, short life (less than 4 months), due to
lack of nucleus
 manufactured in the red bone marrow of the skull, the
ribs, the vertebrae, and the ends of long bones
 destroyed in the liver and the spleen
 when RBC are destroyed, hemoglobin is released, the
iron is covered and is returned to the red bone
marrow, and the heme portions undergo chemical
degradation and are excreted by the liver as bile
pigments
Leukocytes
 white blood cells (WBC)
 less than 1% of the cells in human blood
 about 5,000 – 9,000 cells/mm3
 larger than RBC, with nucleus, no hemoglobin,
essentially colorless
 not confined to the bloodstream, migrate out into the
interstitial fluid
69
 play important function in the immune system
Types of leukocyte
1. granulocytes
2. agranulocytes
Types of Granulocytes as to Staining Properties
1. neutrophils
2. eosinophils
3. basophils
Types of Agranulocytes as to Function
1. monocytes
2. lymphocytes
Thrombocytes
 called as platelets in humans
 from fragmentation of megakaryocytes, large
cells in the bone marrow; no nucleus
 involved in blood clotting or coagulation
ABO BLOOD CLASSIFICATION
 the most common blood grouping is the ABO
classification
 based on the types of protein present in the blood cells
(antigen A and antigen B) and in the plasma (anti-a
and anti-b)
70
 agglutination (clumping of blood cells) will form
when antigen A combines with anti-a or antigen b
combines with anti-b
 each blood types contains the following:
Blood type
Type A
Type B
Type AB
Type O
Antigen
Antigen A
Antigen B
Antigen A and B
no antigen
Antibody
anti – B
Anti – A
no antibodies
anti – A & anti - B
Blood transfusion relationships
 blood type A can donate to A and AB and can
receive from A and O
 blood type B can donate to B and AB and can
receive from B and O
 blood type AB can donate to AB and can
receive from A, B, AB, and O and receive from
O, thus called universal donor
THE HEART
 the main pumping organ of the body
 highly muscular organ located in the mid-ventral
region of the thoracic cavity
 enclosed by a tough connective tissue, the
pericardium
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Chambers of the Heart
1. Atria or Auricles – have thin walls, received blood
from the veins and pump it into the ventricle
2. Ventricles – with much thicker walls, pump the
blood out of the heart to all parts of the body
Types of Heart as to Numbers of Chambers
1. two-chambered heart – found in fishes and it has
one auricle and one ventricle
2. three-chambered heart – found in amphibians and
reptiles, it has two auricles and one ventricle. It exhibits
double but incomplete circulation but there is slight mixing
of venous and arterial blood in the ventricle
3. four-chambered heart – found in birds and
mammals, it has two auricles and two ventricles, exhibits
double and complete circulation, no mixing of venous and
arterial blood in the ventricle
The Human Heart
 cone-shaped muscular organ about the size of a fist
 located between the lungs, tilted, the apex is
directed to the left
 internally, the left and right side is separated by a
septum
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 atria and ventricles are separated by atrioventricular
valves, tricuspid valve on the right and bicuspid
valve on the left
 between ventricle and its vessels, regulated by a
semilunar valve, pulmonary and aortic semilunar
valves
The Heartbeat
 about 70 times/minute, each heartbeat lasts about
0.85 sec
 cardiac cycle includes systole (contraction of heart
muscle) and diastole (relaxation of heart muscle)
 contraction is intrinsic (outside nervous stimulation)
due to nodal tissue
 SA (sinoatrial) node in the upper dorsal wall of right
atrium, initiates atrial contraction, also called as
pacemaker
 AV node (atrioventricular) node in the base of the
right atrium, initiates ventricle contraction
 expels 60 ml of blood per beat
THE BLOOD VESSELS
Types of Blood Vessels as to Direction of Blood Flow
Arteries
 carry oxygenated blood away from the heart,
except pulmonary arteries, which carry
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deoxygenated blood away from the heart going to
the lungs; branched into arterioles connecting
small arteries to capillaries
Capillaries
 connect arterioles and venules; about 0.5 to 1 mm
long; could be found in the metabolic organs
Veins
 carry deoxygenated blood towards the heart,
except pulmonary veins, which carry oxygenated
blood towards the heart; branched into venules,
connecting small veins to capillaries
Layers of the Blood Vessels (except capillaries and
venules)
1. tunica intima (inner layer) includes
endothelium
2. tunica media (middle layer) includes elastic
and smooth muscle tissue
3. tunica adventitia or tunica externa (outer
layer)
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CIRCULATION PATTERNS
Pulmonary circulation
 blood flow through the system of blood vessels
that carry blood from the right ventricle of the
heart to the lungs and from the lung and back
to the left atrium
Systemic Circulation
 blood flow through the system of blood vessel
that carry blood from the left ventricle of the heart
to the tissues of the body and back from the body
to the right atrium
PATHWAY OF BLOOD (BLOOD CYCLE)
 body tissues ( capillaries ) – for collection of CO2
and wastes
 venules and veins
 superior and inferior vena cava
 right atrium of the heart
 tricuspid valve
 right ventricle
 pulmonary semilunar valve
 pulmonary aeteries
 lungs (alveoli/capillaries) – for gas exchange
 pulmonary veins
 left atrium of the heart
 bicuspid valve
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




left ventricle
aortic semilunar valve
dorsal aorta
arteries and arterioles
body tissues (capillaries) – for distribution of O2
and nutrients
COMMON BLOOD-RELATED DISORDERS
 Hypertension or High Blood Pressure
 Thrombosis
 Leukemia
 Arteriosclerosis
 Hemophilia
76
RESPIRATORY SYSTEM
FUNCTIONS
 exchange of gases
 oxidation of food molecule in order to produce
energy in the form of ATP
TYPES OF RESPIRATION
Direct Respiration
 exchange of gases between the cells of an organism
and the environment
 essential gases are oxygen and carbon dioxide
Indirect Respiration
 exchange of gases through specialized organs and
involves two phases, external (between blood and
environment) and internal (between blood and body
cells)
RESPIRATORY ORGANS
 Direct Surfaces (skin and pharyngeal regions) – some
amphibians and fishes like mudhopper and eels use
their skin, salamanders use their pharyngeal regions
 Gills – most aquatic animals use external or internal
gill filaments
 Lungs – terrestrial animals
Characteristics of a Good Respiratory Organ
77
 have a large surface area, to accommodate greater
amount of gases
 be thin, for it will take gases the shortest time
possible to pass through it
 be moist, for the gases will be dissolved
 be permeable so that gases dissolved in water can
pass through it
 be accessible to the source of oxygen and be elastic,
to accommodate more air
PARTS OF RESPIRATORY TRACT
 nostrils or external nares – outer opening for entrance
of air
 nasal chamber of cavity – lined with mucus-secreting
and ciliated epithelium
 internal nares – posterior opening connected to the
pharynx
 pharynx – or throat, common passageway of air from
the nasal cavity and food from the oral cavity
 glottis – opening of the cartilaginous larynx, covered
by a flap of tissue, the epiglottis, to prevent food from
entering the glottis when swallowing
 larynx – or voice box containing the vocal chords
 trachea – or windpipe made up of rings of cricoid
cartilages
 bronchi (bronchus) – leading to the lungs
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 bronchioles – smaller branches of each bronchus
(secondary and tertiary bronchi) within the lungs
 alveoli (alveolus) – or air sacs, thin and moist, site of
gas exchange between the alveoli and adjacent blood
capillaries; in man, there are about 300 million alveoli
with a total surface area of about 70 square meter (half
an area of a tennis court)
LUNGS
 composed of elastic tissue and some muscles
 in human, covered by visceral pleura, a thin layer of
smooth epithelium
 located at the pleural cavity lined with parietal pleura
 diaphragm, a dome-shaped muscular partition from
the floor of the chest cavity separates the pleural
cavities from the abdominal cavity
 right lung is divided into three lobes, the left into two
Pulmonary Volume
 tidal volume – volume of air inspired or expired
during quiet breathing, about 500 ml (tidal air; 350 ml
reach the alveoli and 150 ml left in the respiratory
passages)
 inspiratory reserve volume – amount of air that can be
inspired forcefully after inspiration of the normal tidal
volume, about 3000 ml (complimental air)
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 expiratory reserve volume – amount of air that can be
expired forcefully after expiration of normal tidal
volume, about 1100 ml (supplemental air)
 residual volume – volume of air still remaining in the
respiratory passages and lungs after maximum
expiration, about 1200 ml (residual air)
Pulmonary Capacities
 vital capacity – sum of tidal air, complimental air, and
supplemental air, the maximum volume of air that a
person can expel from his respiratory tract after a
maximum inspiration, about 4600 ml
 inspiratory capacity – sum of tidal air and
complimental air, amount of air that a person can
inspire maximally after normal expiration, about 3500
ml
 functional residual capacity – sum of supplemental air
and residual air, amount of air remaining in the lungs
at the end of normal expiration, about 2300 ml
 total lung capacity – sum of tidal air, complimental
air, supplemental air, and residual air, about 5800 ml;
equal to the vital capacity plus the residual air
MECHANICS OF BREATHING
During Inspiration
 diaphragm and other chest muscles contract
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 ribs also expand
 volume of thoracic cavity increases
 the pressure in the lungs fall below atmospheric
pressure
 air rushes in to equalize the pressure through the
nostrils going to the alveoli
During Expiration
 diaphragm and other chest muscles return to normal,
relax position
 ribs also return to normal position
 size of thoracic cavity reduced
 lungs contract forcing the air out due to increase in
pressure
COMMON DISEASES ASSOCIATED WITH
RESPIRATORY SYSTEM





common colds
asthma
bronchitis
pneumonia
tuberculosis (TB)
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EXCRETORY SYSTEM
FUNCTIONS
 collection and elimination of metabolic waste products
 maintains homeostatis
METABOLIC WASTES
 heat
 carbon dioxide from respiration
 water derived from the oxidation of carbohydrates and
fats
 bile salts and pigments from the destruction of RBC
 mineral salts from the breakdown of other worn-out
tissues and from excess dietary intake
 urea from protein metabolism
HUMAN EXCRETORY SYSTEM
 located in the lower abdomen
 excretory structures include the kidneys, urinary
bladder, ureters, and urethra
 the main wastes collected is called urine
 the other organs for excretion include the liver, lungs
and skin
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Kidneys
 paired, bean shaped organs located on both sides of
the spinal column
 around 5 in long 3 in wide and 1 in thick
 composed of over one million nephrons
 organs for homeostatis for they regulate the
composition of the blood
Blood Supply of the Kidney
 renal artery – carry blood with dissolved cellular
wastes into the kidney
 renal vein – carry filtered blood out of the kidney
Internal parts of the kidney
 cortex – outer granulated layer
 medulla – radially striated or lined layer
 renal pelvis – inner space or cavity continuous with the
ureter
Structure of the Nephron
Renal corpuscle or corpuscles of Malphigii
 glomerulus – composed of several looped capillary
vessels which connect afferent arteriole (entry of
blood) with the efferent arteriole(exit of blood)
 Bowman’s capsule – encloses the glomerulus
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Renal tubules
 capsule – expanded as the Bowman’s capsule
enclosing the glomerulus
 proximal convoluted portion – connected to the
capsule, about 14mm in length and 60µm in diameter
 loop of Henle – consisting of two straight (ascending
and descending) limbs running parallel to each other
 distal convoluted portion – short and much convoluted
leading to a short, arched connecting potion, which
empties into a straight collecting duct leading to the
renal pelvis
Steps of Urine Formation
Pressure filtration
-small molecules (water, glucose, amino acids, salts, urea,
uric acids) from the glomerulus were forced by the blood
into the Bowman’s capsule
Selective Reabsorption
- molecules (water, glucose, amino acids, salts) return to
the blood at the proximal convoluted tubule through
diffusion and active transport
84
Tubular secretion
-molecules (uric acid, creatinine, ammonia) from the blood
moved into the distal convoluted tubule through active
transport
Reabsorption of water
-water returns by osmosis following active reabsorption of
salts along the length of the nephron and notably at the
loop of Henle and collecting duct
Excretion
-urine is formed and goes out of the kidney through the
pelvis and ureter going into the urinary bladder for
temporary storage
COMMON KIDNEY DISORDERS
 Acute renal failure
 Chronic renal failure
 Urinary calculi
85
NERVOUS SYSTEM
FUNCTIONS
 coordination and integration of many activities of the
body through the conduction of impulses from the
receptors to the effectors
ORGANIZATION OF THE NERVOUS SYSTEM
Origin
 develops from an embryonic dorsal hollow nerve cord
Composition
 brain, spinal cord, nerve cells, neuroglial cells
 consist of vast increase in the number of neurons
compared to invertebrates
 consists of several types of paired sensory receptors
due to cephalization and bilateral symmetry
Divisions
 Central Nervous System (CNS) – includes the brain
and the spinal chord
 Peripheral Nervous System (PNS) – includes all the
nerve cells outside the CNS, both the cranial nerves
and the spinal nerves
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NEURONS
 nerve cells
 for reception of stimuli and transmission of reactions
 responsible for the integration of impulses
 composition of the brain
Parts of a Neuron
Cell body
-part of a neuron where nucleus and other organelles are
located
Protoplasmic processes
 axon – a long cylinder that conducts nerve impulses
away from the cell body; covered by tightly packed
spiral of Schwann cells containing myelin serve as
insulator and considered as glial cells (with supportive
and nutritive functions)
 dendrite – short, highly branched extensions that
conduct nerve impulses toward the cell body
Types as to Number of Protoplasmic Process
 unipolar neuron – with only one protoplasmic process;
found in dorsal root ganglion of the spinal chord
 bipolar neuron – with two protoplasmic processes
(axon and dendrites); found in the retina of the eye
87
 multipolar neuron – with several dendrites and one
axon; found in ventral horns of the grat matter of the
spinal cord
Types as to Functions
 sensory neurons – transmit impulses from sensory
receptors of the sense organ to nerve center (CNS)
 motor neuron – transmit impulses from the nerve
center to the effectors (muscles or glands)
 adjustor or associative neuron – connects sensory and
motor neuron; located in the nerve center, also called
interneuron
NEUROGLIAL CELLS
 supporting cells of the nervous tissue
 composed of actively dividing cells
 can cause brain tumor
Types as to Structure and Function
 astrocytes – star-shaped neuroglial cells, connect
neurons and capillaries
 microglia – phagocytes, dispose dead cells, bacteria,
etc.
 ependymal – line the fluid-filled cavities of the CNS
for protection
 oligodendrocytes – form the myelin sheath around the
fibers
 Schwann cells and satellite cells
88
CENTRAL NERVOUS SYSTEM
 lies in the midline of the body
 most of the cells are neuroglial cells
 consists of the spinal cord and the brain where nerve
impulses are coordinated and interpreted
Spinal cord
 continuation of the base of the brain surrounded by
vertebrae;
 covered by three protective membranes (meninges);
 the spaces between the meninges are filled with
cerebrospinal fluid (CSF), which cushion and protect
the CNS;
 CSF is also contained in the central canal of the cord;
Two main functions of the spinal cord
 center for many reflex actions;
 provides means of communication between the brain
and the spinal nerves
Gray Matter
 consist of cell bodies and short unmyelinated fibers;
 H-shaped in a cross section;
 includes interneurons and portions of sensory neurons
and motor neurons
89
White Matter
 consist of bundles of myelinated long fibers of
interneurons (tracts)
 connects the spinal cord to the brain
 dorsally, contains ascending tracts taking information
to the brain
 ventrally, contains descending tracts carrying
information from the brain
Brain
 most specialized organ of the body
 located in the cranial cavity of the skull
 made up of soft nervous tissue covered by three
membranes or meninges
Meninges of the Brain
 pia mater – innermost membrane; closely adhering to
the surface of the brain and dipping down into its
many folds; well supplied with blood vessels that
carry food and oxygen to the brain
 arachnoid mater – middle membrane; made up of
fibrous and elastic connective tissues; separated to the
pia mater by the cerebrospinal fluid
 dura mater – outermost membrane; thick and tough
linings of the cranium
90
Hemispheres of the Brain
 left hemisphere – controls the right side of the body
 right hemisphere – controls the left side of the body
Divisions of the Brain
 cerebrum
 cerebellum
 diencephalons (hypothalamus and thalamus)
 the brain stem (medulla oblongata, pons and midbrain)
Cerebrum
 foremost part and largest part (in humans) of the brain
 the seat of consciousness, intelligence, sensory
perception of sight, olfactory, and auditory senses, and
coordination of body movement
 controls the activities of the lower parts of the brain
 can override the functioning of the brain stem and
diencephalons
 can initiate voluntary motor activities and controls the
actions of the cerebellum
 consists of two large masses called cerebral
hemispheres, connected by corpus callosum
Lobes of Cerebrum
 frontal lobe – responsible for the elaboration of
conscious thought and control the movement of
skeletal muscles; includes the motor elaboration,
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articulation, mastication, deglutition, and movement
of tongue, lips, hands, arms and legs
 parietal lobe – responsible for the sensations of
temperature, touch, pressure, and pain from the skin;
includes salivation and sensory elaboration of the
mouth, lips, tongue, hands, arms, and legs
 temporal lobe – responsible for hearing and smelling,
visual and auditory recollection, and perceptual
judgment
 occipital lobe – responsible for vision
Cerebellum
 lies below the posterior portion of the cerebrum
 separated from the brain stem by the fourth ventricle
 functions in muscle coordination, posture and balance
Diencephalon
Hypothalamus
 forms the floor of the third ventricle
 maintains homeostasis of the internal environment
 contains center for regulating hunger, sleep, thirst,
body temperature, water balance, and blood pressure
 controls the pituitary gland, serves as a link between
the nervous and endocrine systems
92
Thalamus
 forms the sides and roof of the third ventricle
 the last portion of the brain for sensory input before
the cerebrum
 serves as a central relay station for sensory impulses
and channels them to appropriate regions of the
cerebrum for interpretation
The Brain Stem
Medulla oblongata
 lies between the spinal cord and the pons, anterior to
the cerebellum
 contains a number of vital centers for regulating
heartbeat, breathing, and blood pressure
 also contains reflex centers for vomiting, coughing,
sneezing, hiccupping, and swallowing
 contains tracts that ascend or descend between the
spinal cord and the brain
Pons
 contains bundles of axons traveling between the
cerebellum and the rest of the CNS
 helps in regulating breathing rate
 contains reflex centers concerned with head
movements in response to visual and auditory stimuli
93
Midbrain
 act as a relay station for tracts passing between the
cerebrum and the spinal cord or cerebellum
 contains reflex centers for visual, auditory, and tactile
responses
PERIPHERAL NERVOUS SYSTEM
 lies outside the CNS
 contains both cranial and spinal nerves
Nerves
 bundles of long neuron fibers held together by
connective tissue
 sensory nerves contain sensory fibers, motor nerve
contain motor fibers, and mixed nerves contain both
types of fibers
Cranial nerves
 in humans, there are 12 pairs of cranial nerves
attached to the brain
 some of these are sensory nerves and others are mixed
nerves
 mainly concerned with the head, neck, and facial
regions of the body
 include the vagus nerve which has branches to the
pharynx and larynx and most of the internal organs
94
Spinal nerves
 in humans, there are 31 pairs of spinal nerves emerged
from the spinal cord
 emerge from the spinal cord by two short roots –
dorsal root and ventral root
 dorsal root contain the axons of sensory neurons
which conduct impulses to the cord
 ventral root contain the axons of motor neurons which
conduct impulses away from the cord
 all spinal nerves are mixed nerves conducting
impulses to and from the spinal cord
Somatic System
 includes all nerves that serve the skeletal muscles
(effectors) and exterior sense organs including those
in the skin (receptors)
 initiate reflex action
Automatic System
 includes all nerves that serve the internal organs
automatically and usually without need for conscious
intervention
 function automatically and subconsciously; innervate
internal organs
 utilize 2 motor neurons (the first has a cell body
within the CNS and a preganglionic fiber, the second
95
has a cell body within the ganglion and a
postganglionic fiber) and 1 ganglion for each impulse
 divided into sympathetic and parasympathetic systems
Sympathetic System
 fight or flight
 norepinephrine (NE) is neurotransmitter
 postganglionic fiber is longer than preganglionic fiber
 preganglionic fiber arises from the middle portion of
the cord
 important during emergency situations
 accelerates heartbeat, dilates the bronchi, increases the
breathing rate
 inhibits digestive tract
Parasympathetic System
 “housekeeper” of the nervous system
 acetylcholine (Ach) is neurotransmitter
 preganglionic fiber is longer than postganglionic fiber
 preganglionic fiber arises from the brain and lower
portion of the cord
 promotes all the internal responses with a relaxed
state; retards heartbeat, promotes digestion
96
Reflexes
 automatic, involuntary responses to changes occurring
inside or outside the body
 some reflexes involve the brain others involve only
the spinal cord and a spinal nerve (reflex arc or spinal
reflex)
Reflex Arc
 major functional unit of the nervous system
 allows us to react rapidly to internal and external
stimuli
Steps of reflex arc
 nerve impulses move along the axon of a sensory
neuron toward the cell body located outside the cord
 from the cell body of the sensory neuron, the impulses
are picked up by an interneuron lies within the cord
 then pass to the dendrites and the cell body of a motor
neuron that lies ventrally within the cord
 the impulses will leave the cord by way of the ventral
root traveling along the axon of the motor neuron
going to the muscle fibers, which contracts
TYPES OF RECEPTORS
Chemoreceptors
 stimulated by changes in the chemical concentration
of substances
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 located in the nasal cavity and the tongue as olfactory
receptors
Thermoreceptors
 stimulated by changes in temperature
 located in the skin as free nerve endings
Mechanoreceptors
 stimulated by changes in pressure and movement
 located in the inner ear, skin, and muscles and tendons
as hair cell, specialized nerve endings and as free
nerve endings respectively
Photoreceptors
 stimulated by light energy
 located in the retina of the eyes as rods and cones
Pain receptors
 stimulated by tissue damage
 located widespread in the body as free nerve endings
COMMON DISEASES ASSOCIATED WITH
NERVOUS SYSTEM
 Epilepsy
 Multiple Sclerosis (MS)
 Meningitis
 Mental illness
 Stroke
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ENDOCRINE SYSTEM
FUNCTIONS
 Coordinates, together with the nervous system, the
activities of the body
 Involved in the synthesis and secretion of hormones
 Hormonal functions include:
 control of energy production and utilization
 control of the composition of extracellular
water and electrolytes
 maintains normal growth and development
ENDOCRINE GLANDS
 ductless glands that synthesize and secrete hormones
 a hormone is an organic substance needed by the body
in minute quantities to elicit a specific physiological
response
 hormones are produced by one part of the body that
have an effect on specific target cells located in
different parts of the body
Hypothalamus
 a small gland about 1.0 cm in diameter located at the
base of the brain
 intimately associated with the pituitary gland
 secretes releasing hormones that travel via a portal
system and stimulate the anterior pituitary
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 Pituitary Gland
 a small gland located at the base of the brain in the
depression of the skull
 connected to the brain through a short stalk called
infundibulum
Divisions of the pituitary gland
 anterior lobe or adenohypophysis
 secretes 6 hormones
 FSH, follicle-stimulating hormone
 LH, luteinizing hormone (in female) or
ICSH, interstitial cell-stimulating hormone
(in male)
 luteotrophic hormone or prolactin
 ACTH, adrenocorticotrophic hormone
 TSH, thyroid-stimulating hormone
 STH, somatotrophic hormone or GH, growth
hormone
 posterior lobe or neurohypophysis
 secretes 3 hormones:
 vasopressin, for constriction of the vessels
 ADH, antidiuretic hormone
 oxytoxin, controls smooth muscles
Thyroid Gland
 composed of two lobes, on each side of the trachea
connected by an isthmus
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 secrete thyroxin that regulate growth and development
 enlargement of this gland results in a condition known
as goiter
Parathyroid Gland
 small glandular bodies located on the dorsal surface of
the thyroids
 secrete parathormones (PTH) that maintains the ration
of calcium and phosphorus in the body
Thymus Gland
 located between the upper part of the sternum and the
pericardium
 a temporary organ which reaches greatest
development at age 14 to 16
 secretes thymosin that controls metabolic rate and
involved in the formation of WBC
Adrenal Cortex
 secretes cortisol and aldosterone that causes
gluconeogenesis and sodium retention and potassium
excretion in the kidneys respectively
Adrenal Medulla
 two small masses located above the kidneys
 secrete epinephrine and norepinephrine
 promotes “fight or floght” reactions during emergency
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Pancreas
 both an exocrine and endocrine gland
 the endocrine part consists of the islets of Langerhans
that secrete the hormones insulin
 insulin lowers the blood sugar, little secretion resulted
into diabetes mellitus
Gonads
 the interstitial cells (Leydig cells) of the testes secrete
testosterone
 the follicles of the ovary secretes estrogen, the corpus
luteum secretes progesterone
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REPRODUCTIVE SYSTEM
Function:

ASEXUAL REPRODUCTION
 only one parent is involved
 no special reproductive organs or cells are required
 ensures rapid increase in number
 exhibited only among lower forms of life such as bacteria,
fungi and lower forms of invertebrates
Methods of Asexual Reproduction
 Fission – the body of the parent is divided into two
approximately equal parts, transverse or longitudinal, each
of which develops into a new individual similar to the
parents; common among protozoan
 Budding – the organism is unequally divided and the new
individual evolves as an outgrown (bud) from the parent;
common in hydra and freshwater sponges
 Fragmentation – the individual breaks or splits into two or
more parts, each part capable of becoming a complete
individual; common among flatworms and echinoderms
 Sporulation – the numerous cells produced are enclosed in a
cyst-like structure so that a part of it surrounds each of the
several daughter nuclei after repeated divisions; common
among sporozoans; also called multiple fission
 Regeneration – the capacity to replace or regenerate parts
lost by injury; common among echinoderms and planaria
103
SEXUAL REPRODUCTION
 involves two parents, male and female
 each parent is provided with a reproductive organ
(gonad) for the production of reproductive cells
(gametes)
 for the male, gonads are paired testes that produce the
sperm cells
 for the female, gonads are paired ovaries that produce
the egg cells
Methods of Sexual Reproduction
 Conjugation – two individuals fuse together and
exchange micronuclei and then separate to continue
binary fission; common among protozoan and ciliates
 Parthenogenesis – a modified form of sexual
reproduction wherein an unfertilized egg develops into
a complete individual; common among rotifers, ants,
bees, and crustaceans
 Hermaphroditism – both male and female sex organs
are present in the same individual (hermaphrodite or
monoecious) but does not reproduce by selffertilization; two individuals exchange germ cells with
each other in cross-fertilization; common among
lower forms of animals, such as flatworms and
earthworms; some do reproduce by self-fertilization
such as tapeworms and snails; protoandry, if the
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sperm cells are formed first; protogyny, if the egg
cells are formed first
 Biparental reproduction – exhibited by dioecious
animals; it involves separate and distinct male and
female individuals, each of which has its own
reproductive system; fertilization may take place
externally or internally
HUMAN MALE REPRODUCTIVE SYSTEM
 Sex organs (gonad) – testes
 Sex cells (gametes) – sperm cells
 Sex hormones – testosterone
External structure
Penis
 the copulatory organ, responsible for the transfer of
sperm cells into the female reproductive tract
 cylindrical organ that usually hangs (flaccid) in front
of the scrotum
 composed of the shaft, glans penis and a foreskin
(prepuce) covering the glans penis
 composed of 3 cylindrical columns of spongy, erectile
tissue containing blood spaces
 during sexual arousal, arterial blood flow fills the
blood spaces in the erectile tissue that causes erection
 the release of semen is called ejaculation
105
Scrotum
 pouch containing the testes that hangs down as an
appendage of the body
 also serves as a thermoregulator to protect the
sperm cell against changes in body temperature
(1.0 to 1.5oC cooler than the body temperature)
Internal Structure
Testes
 the male sex organ
 suspended within the scrotal sac of the scrotum
 composed internally of numerous seminiferous
tubules embedded within the interstitial cells
 seminiferous tubules are responsible for the
formation of the male gametes, sperm cells;
immature sperm cells move from the
seminiferous tubules to the epididymis to
mature, about 20 days
 interstitial cells are responsible for the
production and secretion of the male sex
hormones, testosterone
Ducts
 tubes that conduct the sperm cell/semen
 vas eferens (vasa eferentia) – tiny tubes
connecting the seminiferous tubules of the
testis to the coiled epididymis;
106
 epididymis (epididymides) – the coiled part of
the sperm duct that lies near the testis for
temporary storage of matured sperm;
 vas deferens (vasa deferentia) – coiled tube
carrying sperm from the epididymis to the
urethra during ejaculation;
 ejaculatory duct – a part of the sperm duct
connecting the vas deferens to the urethra
where fluid secreted by the sex glands are
mixed with the sperm
 urethra – the tube that conducts both the urine
from the urinary bladder and the semen from
the testes during ejaculation
Glands
 organs that produces seminal fluid
 seminal vesicle (vesicular gland) – lie at the
base of the bladder, joining the vas deferens to
form the ejaculatory duct, secrete thick, viscous
fluid containing fructose and alkaline substance
for the survival of the sperm
 prostate gland – a mass of glandular tissue at
the base of the urethra that secretes an alkaline
fluid that has a stimulating effect on the sperm
as they are released
 Cowper’s gland (bulbo-urethral gland) –
located slightly below the prostate gland
secreting mucous fluid for lubrication
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HUMAN FEMALE REPRODUCTIVE ORGAN
 Sex organs (gonads) – ovaries
 Sex cells (gametes) – egg cells
 Sex hormones – estrogen and progesterone
External Structure (collectively called as vulva, the
external female genitali)
 Mons pubis (mons veneris)
 a pad of a fatty flesh located above and in front
of the labia, normally covered with pubic hair
after puberty
 Labia
 two sets of lips that protect the entrance to the
vagina; made up of outer and larger folds of skin
covered with pubic hair called labia majora and
inner labia minora located beneath the labia
majora
 Clitoris
 A bud or projection of sensitive erectile organ
located at the anterior part of the labia at the
juncture of the labia minora, often hidden
beneath a hood of flesh called the prepuce
 Vestibule
 the opening into the vagina, normally guarded
by a thin membrane called hymen in the virgin
state
108
 Urethral opening
 opening of the urethra for the excretion of urine
Internal Structure
 Ovary
 the female sex organ
 lodged within the peritoneal cavity where they
are held in position by mesenteries or ligaments
 composed internally of numerous follicle each
containing an egg cell
 follicles contain the female gamete, egg cell, that
will undergo maturation for a cycle of 28 days
 also responsible for the production and secretion
of the female sex hormones, estrogen before
ovulation and progesterone after ovulation
 ovulation is the release of egg cell (secondary
oocyte) from the follicle of the ovary
 Fimbriae
 fingerlike projections at the end of each oviduct
that capture or sweep the egg cell during
ovulation
 Fallopian tube (oviduct)
 the egg carrying tubes extending from the ovaries
to the uterus where fertilization takes place
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 the inner wall is lined with cilia for the propulsion
of the egg during its course down to the uterus for
about 12 to 24 hours
 Uterus (womb)
 special hollow organ where the embryo develops
for 9 months during pregnancy; provided with
thick muscular wall, numerous blood vessels and
specialized lining called endometrium
 implantation of the fertilized egg cell takes place
a week after fertilization
 varies with different mammals, simplex in man,
duplex in rodents, bicornuate in horses and
bipartite in cats
 Cervix
 a muscular ring of tissue at the mouth of the
uterus protruding into the vagina
 Vagina
 hollow muscular tube leading to the outside, with
elastic wall not only for the reception of the male
penis during copulation but also for the passage
of infant during childbirth
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SEX HORMONES
 hypothalamus controls the sexual functions of the
gonads, it secretes gonadotropin-releasing hormone
(GnRH) that stimulates the anterior pituitary gland to
produce follicle stimulating hormone (FSH) and
luteinizing hormone (LH), LH is called interstitial
cell-stimulating hormone (ICSH) in males
 FSH promotes formation and maturation of sperm
cell (spermatogenesis) in the seminiferous tubules of
the testes and the development of an egg cell
(oogenesis) in the follicle of the ovary
 LH promotes the development of the corpus luteum
which secretes progesterone
 ICSH controls the production of testosterone by the
interstitial cells
Testosterone
 the main sex hormone in males
 produced by the interstitial cells of the testes
 essential for the normal development and functioning
of the reproductive organs
 necessary for the maturation of sperm cells
 brings about and maintains the secondary sexual
characteristics that develop during puberty stage:
taller heights
broader shoulders
deeper voice
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greater muscular development
hair on face, chest arms, legs and other parts
of the body
causes receding hairline and baldness
Estrogen and progesterone
 main sex hormones in females
 estrogen is produced by the developing follicle of the
ovary and progesterone by the corpus luteum after
ovulation
 estrogen is essential for the normal development and
functioning of the reproductive organs
 mainly estrogen brings about and maintains the
secondary sexual characteristics that develop during
puberty stage
soft and rounded body appearance due to
greater accumulation of fats beneath the skin
softening of the skin
wider hips due to the enlargement of the pelvic
girdle
both estrogen and progesterone are responsible
for the development of the breast
MENSTRUAL CYCLE
Ovarian Cycle
 primary follicles containing primary oocytes begin
producing estrogen
112
 secondary follicles containing secondary oocytes
continue producing estrogen
 graafian follicle develops
 secondary oocytes surrounded by follicle cells is
released (ovulation)
 corpus luteum produces progesterone
 corpus luteum degenerates
Uterine Cycle
Menstrual Period (from day 1 to 5)
 low level of female sex hormones in the body
causing the uterine lining to disintegrate and its
blood vessels rupture
 a flow of blood (menses) passes out of the
vagina (menstruation)
Proliferative phase (day 6 to 13)
 increased production of estrogen by an ovarian
follicle causes endometrium to thicken and to
become vascular and glandular
Ovulation (day 14)
 graafian follicle burst and the secondary oocyte
is released from the ovary
113
Secretory phase (day 15 to 28)
 increased production of progesterone by the
corpus luteum causes the endometrium to
double the thickness and the uterine glands to
mature
 producing a thick mucoid secretion ready to
receive the developing embryo
EMBRYOLOGY
 concerned with the origin of the body structures of
an individual and its developmental processes
 the study of the development of an egg from the
time of its maturation until the organism is
completely formed
 embryo refers to the offspring in the uterus from
weeks 2 through 8 of development
EMBRYONIC MEMBRANES
1. Amnion – a thin membrane derived from the
embryonic cell layers that forms a fluid – filled
pouch, which loosely envelops the embryo and
fetus until birth
2. Chorion – a membrane derived from embryonic
cell layers that surrounds and protects the embryo
and fetus, part of the chorion joins with the uterine
lining and develops into the placenta
114
3. Allantois – a membrane derived from the
embryonic tissue that contains blood vessels which
develops into the blood vessels of the umbilical
cord
4. Yolk sac – a balloon – like membrane surrounding
a cavity containing nutrients and blood cells for the
embryo from week 2 after fertilization until the
placenta has fully developed
COMMON SEXUAL DISEASES AND
DYSFUNCTION











Erectile dysfunction
Female orgasmic dysfunction
Vaginismus
Breast Cancer
Sterility
Infertility
Gonorrhea
Syphilis
Genital herpes
AIDS
Trichomoniasis
115
BASIC GENETICS:
DEFINITION OF TERMS
 Genetics – the study of heredity and variation
 Heredity – the transmission of traits from one
generation to another, from parents to offspring; the
protoplasmic continuity between parents and offspring
 Variation – any difference existing between
individuals of the same species
 Chromosome – rod-shaped in the nucleus of
eukaryotes and prokaryotes that contains the
hereditary units or genes; seen particularly during cell
division
 Gene – the unit of heredity occupying a particular
location on the chromosome and passed on to
offspring
 Locus – the location of a gene on a chromosome
 Diploid – the 2N number of chromosomes; twice the
number of chromosomes found in gametes
 Haploid – the N number of chromosomes; half the
diploid number; the number characteristic of gametes
that contain only one set of chromosomes
 F1 generation – first filial generation; the firstgeneration offspring of a genetic cross that has at least
two generations
 F2 generation – second filial generation; the second
generation offspring of a genetic cross
116
 Homozygous – a pair of similar or like genes for any
one character
 Heterozygous – a pair of contrasting traits of two
kinds of genes
 Genotype – the particular genes of an individual that
determine a specific trait
 Phenotype – the outward appearance of an organism,
caused by genetic and environmental influences
 Allele – a pair of similar or contrasting characters; one
of two or more alternative states of a gene
 Dominant allele – hereditary factor that expresses
itself when the genotype is heterozygous
 Recessive allele – hereditary factor that expresses
itself only when the genotype is homozygous
 Hybrid – the offspring of two parents that differ in
one or more heritable characters
 Monohybrid cross – cross in which the parents differ
in one pair of alternative characters
 Dihybrid cross – cross in which the parents differ in
two pairs of alternative characters
 Homologous chromosomes – a pair of chromosomes
that have the same shape and contain genes for the
same traits
 Mutation – a sudden change in the genetic make-up;
an abrupt and heritable modification of a character
117
TESTCROSS
 used to determine if an individual expressing
dominant trait is homozygous or heterozygous
 the results indicate whether an individual who has
phenotype is heterozygous or homozygous
 if any of the offspring of a testcross have
phenotype determined by the recessive allele,
parent with the dominant phenotype must
heterozygous
the
the
the
the
be
MONOHYBRID CROSS
 one-trait testcross
 if the parent expressing the dominant trait is
homozygous, none of the offspring will show the
recessive characteristics
 but if the parent expressing the dominant trait is
heterozygous, there is a 50% chance that any offspring
will show the recessive characteristics
DIHYBRID CROSS
 two-trait testcross
 if the parent expressing the dominant trait is
homozygous, one of the offspring will show the
recessive characteristics
 but if the parent expressing the dominant trait is
heterozygous, there is a 75% chance that an offspring
will show at least one of the recessive characteristics
118
PUNNETT SQUARE
 a “checkboard” grid designed to determine all possible
genotypes produced by a given cross
 introduced by poultry geneticist, R. Punnett in early
1900’s
GREGOR JOHANN MENDEL
 an Austrian Augustinian monk; born in 1822 to
peasant parents;
 studied science and mathematics at the University of
Vienna where he failed an exam for a teaching
certificate;
 taught natural science at a local technical school;
 formulate center laws of heredity in early 1860’s;
Before Mendel
 the belief was Blending Theory of Inheritance;
 both sexes contribute equally to a new individual;
 a cross between plants with red flowers and plants
with white flowers would yield only plants with pink
flowers;
The Work of Mendel
Mendel’s Experiments
 he chose to work with the garden pea, Pisum sativum;
this plant was easy to cultivate and had a short
generation time;
 he choose 22 varieties of peas;
 when these varieties self-pollinated, the offspring
were like the parent plants and like each other;
119
 he cross-pollinated the varieties for his experiment;
 studied the inheritance of relatively distinguishable
traits seed shape, seed color, and flower color;
 he followed the inheritance of individual traits, he
gathered statistical data and used his understanding of
mathematical laws of probability to interpret the
results.
Mendel’s Conclusion
Mendel’s First Law: LAW OF SEGREGATION
 “Each organism contains two factors for each traits,
and the factors segregate (separate) during the
formation of gametes so that each gamete contains
only one factor for each trait. When fertilization
occurs, the new organism has two factors for each
trait, one from each parent.”
Mendel’s Second Law: LAW OF INDEPENDENT
ASSORTMENT
 “Members of one pair of factors segregate (assort)
independently of members of another pair of factors.
Therefore, all possible combinations of factors can
occur in the gametes.”
SOLVING GENETIC PROBLEMS
 Know which characteristic is dominant.
120
 Decide on the appropriate key. Recommended use is
the first letter of the recessive trait.
 Determine the genotype of the parents.
 Determine all possible types of gametes for both
parents.
 Choose what method will be used, Punnett square or
forked-line method.
Some common human traits
Human traits
Dominant
Skin
Freckles
Pigmentation
Hairline
Widow’s peak
Unattached
Earlobes
(Free lobes)
Red-green
Color vision
vision
Hair on back of
Present
hand
Left thumb over
Interlace fingers
right
Bent towards
Bent little finger
ring finger
Hair form
Curly hair
Eye lashes
Long eyelashes
Ability to curl
Tongue
tongue
121
Recessive
No freckles
Continuous
Attached
Red-green
blindness
Absent
Right thumb
over left
Straight
Straight hair
Short eyelashes
Inability to curl
the tongue
SEX-LINKED TRAITS (HUMAN)
 Genes which are carried on the sex chromosomes,
mostly on the X chromosomes only and not on the Y
 There are now more than 120 known sex linked traits
in humans.
FEW EXAMPLES OF SEX-LINKED TRAITS:
TRAITS
DESCRIPTIONS
1. HEMOPHILIA
 a condition where the
blood lacks agents
necessary to cause
clotting
of
blood
following an injury
 a heredity disorder
common among the
royal families
2.COLOUR
 the inability of an
BLINDNESS
individual
to
distinguish
between
the colours red and
green
3. OPTIC TROPHY
 a deterioration of optic
nerve
4.JUVENILE
GLAUCOMA
 a condition leading to
hardening
of
the
eyeball from increased
internal pressure
122
 a condition where a
person can see objects
clearly close up but not
a distance
 premature loss of hair
common among males
5.MYOPIA
6. BALDING
Each Human cell contains 23 pairs of chromosomes,
including the two sex chromosomes (xy)
Number of chromosomes in Human – 46
Female eggs
22pairs
of somatic chromosomes and
X – sex chromosomes
22-X (Homogametic sex)
MALE SPERM
22-X
22-Y
(HETERO GAMETIC SEX)
123
CHROMOSOMAL BASIS OF SEX
DETERMINATION
22
X
22
X
Egg
sperm
[P(x)=1] [P(x)=1/2]
22
X
Egg
[P(x)=1]
44
XX
22
Y
sperm
[P(y)=1/2]
44
XY
FEMALE ZYGOTE
MALE ZYGOTE
SIGNIFICANCE
OF
SEX
CHROMOSOMAL
ABERRATIONS (ABNORMALITIES)
CAUSES:
1. Nature also makes mistakes. Certain mechanisms may
fail during meiosis or mitosis, causing failure of the
homologous chromosomes to separate during anaphase
(non-disjunction) producing certain eggs with two xchromosomes or none (22-xx or 22-o) instead of one (22x)
124
2. ENVIRONMENTAL FACTORS
 increasing chemical pollution
 drug abuse
 viral infections
 ionizing radiation (gamma, x-ray, beta or alpha
particles)
 radio isotopes in medicine, industry
 radioactive wastes from nuclear reactors
 fallouts of nuclear weapon testing
THE HUMAN GENETIC DISORDER:
 CYSTIC FIBROSIS – condition arises from the
production of abnormal amounts of mucous secretions
by the lungs and the pancreas
 HUNTINGTON’S DISEASE – a nervous disorder
which usually appear between 35 and 45 years of age
(mid-life)
- symptoms includes loss of memory, severe
depression, anger, difficulty in speaking and
swallowing
 PHENYLKETONURIA (PKU) – a disease caused
by the inability of the body to produce a specific
enzyme required to break down a protein in itself.
125
CHROMOSOMAL DISORDERS:
1. DOWN SYNDROME (MONGOLISM)
 No. of chromosomes (47) with extra 21 chromosomes
CHARACTERISTICS:
 mental retardation
 poor muscle development
 large tongue
 slanted eyes
 flat forehead
2. KLINEFELTER’S SYNDROME
 No. of chromosomes (47) with extra x chromosome
(xxy)
 small testes
 sterility (devoid of germ cells)
 tall, slim
 with developed breast
 frequent mental retardation
3. TURNER’S SYNDROME
 No. of chromosomes (45) with the x chromosome
only (xo)
 failure to develop secondary sex characteristics of
female
 short stature
 webbed neck
126
 flat chested
 sterility in females
4. SUPER MALE/META MALE
 No. of chromosomes (47) with extra y chromosomes
(xyy)
 neither the super/bionic man nor the usual male sex
symbols
 mental retardation
 possible cause of violent behavior
5. SUPER FEMALE/METAFEMALE
 No. of chromosomes (47) with extra x chromosome
(xxx)
 neither the super/bionic woman nor the usual female
sex symbols
 mental retardation
 short, stocky, flat chested
 generally sterile
TREATING/DETECTING GENETIC DISORDERS
OR DISEASES
 KARYOTYPING – process that can be used to detect
a number of chromosomal abnormalities which in turn
are indicators of possible future genetic disorders
 AMNIOCENTESIS – a prenatal diagnostic technique
in which amniotic fluid is removed and the cells
127
present used to produce a karyotype of the fetus which
can yield vital information in detecting any
abnormalities
 ULTRA SOUND – technique that enables the doctor
to locate the exact position of the fetus ona monitor,
thus ensuring the fetus is not accidentally injured
during amniocentesis
 POST NATAL DIAGNOSIS – very useful in the
detection of genetic disorders of biochemical origin
a. SERUM TEST (blood extraction)
- can detect cystic fibrosis
-immediate medical treatment such as antibiotics
and pulmonary therapy can extend the life
expectancy
b. PKU SCREENING- done on all new borns
within the first two weeks of birth
- has lead to a decrease in the number of fatalities
caused by PKU (phenylketonuria)
GENE TECHNOLOGY (The Artificial Intervention in
Genetics)
 BIOTECHNOLOGY – the use of scientific and
engineering principles to manipulate organisms.
 GENETIC ENGINEERING – the science applied
to the manipulation of genes to improve the
characteristics of plants and animals, to produce
128
medically important products and to treat genetic
disorders in humans
TYPES:
A. CLONING – the process extracting or isolating the
chromosomes of one organism from the nucleus of the
cell, synthesizing the DNA, then inserting it to another
organism of the same species to produce the desired copies
or CLONES
B. EMBRYO TRANSPLANT – the removal of an
embryo from one female organism (or a test tube) to place
the embryo in another female organism
EXAMPLE:
 TEST TUBE BABIES - are form of embryo
transplant. The donor sperm is combined with a
recipient egg and fertilization occurs in vitro (in
glass). The fertilized egg is then inserted into the
female uterus by syringe.
C. ARTIFICIAL INSEMINATION – the process of
mechanically placing the sperm in the vagina or uterus,
after which fertilization is allowed to occur naturally
- used in animal breeding
- means to preserve some animal species in danger of
extinction
-solved the problem of infertility in human
129
D. RECOMBINANT DNA – “GENE SPLICING
TECHNOLOGY”
-the product of genetic engineering in which pieces or
small fragments of DNA from plant or animal cells are
combined to form new sequences
Example.
PLASMID
microorganisms/bacteria
TECHNOLOGY
in
PRODUCTS FROM GENETICALLY ENGINEERED
MICROBES
 INTERFERONS – group of antiviral compounds that
may treat few forms of cancer (skin cancer) like
melanoma and leukemia
-fight viral infection
-boost the immune system
-relieve rheumatoid arthritis






INSULIN
GROWTH HORMONE
PLASMINOGEN ACTIVATOR
TUMOR NECROSIS FACTOR
INTERLEUKIN 2
ENZYMES
130
CLASSIFICATION AND NOMENCLATURE
IMPORTANT TERMS:
 SYSTEMATICS – the study of the diversity of
organisms at all levels of organizations
-includes the taxonomy and classification of organisms
 TAXONOMY – deals with identification and naming
(nomenclature) of organisms
 PHYLOGENY – the evolutionary history of a group
of organism; the scientific basis of classification
 IDENTIFICATION – recognition of certain
distinguishing characters of the plant specimen; results
in the comparison of the specimen with similar
specimens
 DESCRIPTIONS –the listing of features/characters
of the plant specimen
 CLASSIFICATION –arrangements of plants into
groups having common characteristics
-results in the placing of plants into a hierarchy of
ranks or categories
 NOMENCLATURE –the orderly application of
binomial names to a particular taxon
CARL VON LINNE (1707-1778)
LINNAEUS”
 known as the proponent of Taxonomy
131
“CAROLUS
 introduced the use of Binomial System of
Nomenclature for all species
 published 2-volume set of Species Plantarum in 1753
which included 7,300 kinds of plants
TAXONOMIC CATEGORIES
 The group of organisms in a particular category is
called taxon
 Each of the category could be subdivided into three
additional categories as in SUPERORDER, ORDER,
SUBORDER, and INFRAORDER
THE SEVEN OBLIGATORY HIERARCHICAL
CATEGORIES
KINGDOM – maybe composed of several phyla or
division
PHYLUM – (Division in plants) maybe composed of
several classes
CLASS – maybe composed of several orders
ORDER –maybe composed of several families
FAMILY – maybe composed of several
genera
GENUS – maybe composed of several
species
SPECIES- maybe composed of
several subspecies or
varities
132
EXAMPLE/CLASSIFICATION OF HUMAN:
KINGDOM Animalia
PHYLUM Chordata
CLASS Mammalia
ORDER Primates
FAMILY Hominidae
GENUS Homo
SPECIES sapiens
SCIENTIFIC NAME: HOMO SAPIENS
SCIENTIFIC NAME
 A binomial nomenclature given to a particular species
 Composed of the Generic name (genus) and species
epithet
 Should be treated in Latin or should be Latinized
 Should be underlined separately or italized
 Latin is used to avoid jealousy among scientific
community
 Should follow the rules and recommendations set by
the International Code of Botanical/Zoological
Nomenclature (ICBN)
 The universal standard name for any organisms
133
KINGDOM OF ORGANISM
I.TWO KINGDOM SYSTEM
 proposed by Aristotle, kingdom Plantae (immobile)
and kingdom Animalia (mobile)
II. THREE KINGDOM SYSTEM
 proposed by German scientist, Earnst Haeckel (1866),
adding kingdom Protista for unicellular organisms
III. FOUR KINGDOM SYSTEM
 proposed by H.F. Copeland (1938) adding kingdom
Mychota (Monera) for the Prokaryotes and renamed
Prostita to Protoctista for the Protozoan and Fungi
IV. FIVE KINGDOM SYSTEM
 proposed by R.H. Whittaker (1957) revised the earlier
arrangements into 5 kingdoms
MONERA,
PROTISTA, FUNGI, PLANTAE AND ANIMALIA
 unnatural and not based on phylogeny
 criteria used in classification are types of cells
(prokaryote and eukaryote), mode of nutrition
(autotrophs and heterotrophs), motility and life cycles
 most commonly used, especially for academic
purposes
V. EIGHT KINGDOM SYSTEM
 proposed by American Molecular Biologist, C. Woese
(1990) and introduced the concept of domain based on
phylogenetic evolution and molecular data
134
 organisms are arranged in phyletic sequence divided
into three domains, BACTERIA, ARCHAEA AND
EUKARYA
DOMAIN I.
Kingdom I.
DOMAIN II.
Kingdom 2.
DOMAIN III.
Kingdom 3
Kingdom 4
Kingdom 5
Kingdom 6
Kingdom 7
Kingdom 8
BACTERIA
Eubacteria (typical bacteria)
ARCHAEA
Archaeabacteria (Achaic bacteria)
EUKARYA
Archezoa (ancient animals)
Protista (protozoans)
Chromista (brown algae)
Plantae (red and green algae) and plants
Fungi
Animalia
VIRUSES – exceptional form of living things
- not included in the kingdom of classification
- borderline forms between living and non-living
things
135
I. KINGDOM: MONERA
A. PHYLUM: SCHIZOPHYTA (BACTERIA)
 the only representative of kingdom Monera
 most abundant and most common organisms on earth
 believed to be the first form of life on earth
 no membrane-surrounded nucleus (prokaryotes)
 the simplest and smallest living organisms. less than
1µ (micron) or 0.01mm in length
TYPES OF BACTERIAL CELLS
A. AS TO SHAPE
1. Coccus (cocci) – sphere shaped or globular
2. Baccilus (bacilli) – cylindrical or rod shaped
3. Sprillum (spirilla) – spiral or corkscrew shaped
B. AS TO GRAM POSITIVENESS (cell wall
components)
1. Gram positive bacteria – colored violet after staining
with gram-staining solution
 with murein in cell wall
2. Gram negative bacteria – colored red after staining with
gram staining solution
 no murein the cell wall
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C. AS TO NUTRITIONAL REQUIREMENTS
1. Lithotrophs (Antotrophs) – organisms that depend on
inorganic matter for growth
2. Organotrophs (Heterotrophs) organisms that depend on
organic matter fro growth
D. AS TO OXYGEN REQUIREMENTS
1. AEROBES
a. Obligate aerobes – when they survive mainly in the
presence of atmospheric oxygen
b. Facultative aerobe – basically anaerobic organisms but
are able to survive in the presence of atmospheric oxygen
2. ANAEROBES
a. Obligate anaerobes – survive mainly in the absence of
atmospheric oxygen
b. Facultative anaerobes – basically aerobes but can
survive even in the absence of atmospheric oxygen
3. MICROAEROPHILES – organisms that survive in the
presence of small amount of atmospheric oxygen
E. AS TO THERMAL REQUIREMENTS
1. Psychrophilic – organisms grow at a temperature below
100C; cold-loving organisms
2. Mesophilic – organisms grow around 37oC
3. Thermophilic – grow at 45oC or more
most organisms grow as mesophiles.
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F. AS TO PH REQUIREMENT
1. Acidophilic – organisms prefer an acidic environment
2. Basophilic - organisms prefer an alkaline environment
BACTERIA maybe
1. Pathogenic – related to the production of disease
process in man
2. Non-pathogenic – do not caused diseases in man
 SAPROPHYTIC – as saprophytes they are involved in
the following activities:
a. decomposition of dead matter
b. soil fertilization (nitrogen cycle)
c. sewage purification
d. useful in industrial processes
e. useful in food manufacture
f. used in genetic engineering for the production of some
useful substances such as “interferons” insulin, growth
hormones and others
g. some are agents of diseases like…






cholera
diphtheria
tuberculosis
abscesses
bubonic plague
leprosy
bacterial dysentery
whooping cough
gonorrhea
pneumonia (strep.)
U.T.I.
tetanus
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B. PHYLUM: CYANOPHYTA (Blue-green algae)
 most primitive kind of algae commonly called
“seeweed” or “water moss”
 closely related to bacteria
 considered autotrophs or self-feeders
 contains chlorophyll A (green pigment), carotene and
xanthophylls
(yellow),
phycocyanin
(blue),
phycoerythrin (red)
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II. KINGDOM: PROTISTA
 mostly unicellular; live in fresh water, salt water or
moist places
 free-living or parasitic
 cells have nuclei (eukaryotic type)
 live singly or colonial: each cell colony can perform
all life processes
 divided into plant-like protests (ALGAE) and animallike protists (PROTOZOA)
A. ALGAL PROTISTS
 aquatic organisms capable of photosynthesis
 part of phytoplanktons
 possess chloroplast and cell wall
 store reserve food
 usually unicellular, some are colonial and
multicellular
 classified according to their color: green, brown,
golden brown and red algae
1. PHYLUM CHLOROPHYTA (green algae)
 mostly marine; closely related to the first plants;
possess clorophylls a and b
 stored reserve food as starch inside the chloroplast
 may reproduce sexually and asexually
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Examples:
Spirogyra, volvox, ulva, oedegonium
2. PHYLUM PHAEOPHYTA (brown algae)
 grow along the shoreline
 commonly called as “seeweeds”
 possess chlorophyll a and b, and FUCOXANTHIN
 store reserve food as laminarin
 source of ALGIN, a pectin-like material that is added
to ice cream and other cream products for smooth
consistency
Examples:
Laminaria, focus, sargassum
3. PHYLUM CHRYSOPHYTA (golden brown, yellow
green, diatoms)
 the most numerous unicellular algae in the oceans and
in freshwater habitats
 contains chlorophyll a, carotenes and xanthophylls
 cell wall has an outer layer of silica
 important source of food and oxygen
Examples:
Vaucheria, synura pinnularia, navicula (diatoms)
4. PHYLUM PYRROPHYTA (Dinoflagellates)
 bounded by protective cellulose plants
 most have 2 flagella
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 possess chlorophyll a and c, carotenes and fucoxanthin
(yellow brown pigment)
 extremely numerous in the oceans
 frequently color coastal waters orange, red or brown
as indications of RED TIDES
 they produce neurotoxin that can cause paralysis of
respiratory muscles
 some are luminescent called “fire plants”
Examples: Gymnodinium, Gonyaulax
5. PHYLUM RHODOPHYTA (red algae)
 multicellular eukaryotes
 live in warmer sea water
 possess chlorophyll a and phycobilins
 reserve food is glycogen – like floridean starch
 source of agar used commercially to make capsules
for vitamins and drugs
 used as base materials for cosmetics
 used as culture medium for bacteria and in food
preparation (baking, dessert, jellies)
Examples: Halymenia, Galaxaura
6. PHYLUM EUGLENOPHYTA (Euglenoid flagelattes)
 unicellular aquatic protests about 500 species
 possess one to several flagella
 show both the characteristics of plants and animals
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 plant-like because they have chloroplast that contains
chlorophyll and can manufacture food by
photosynthesis (autotrophs)
 animal-like because they lack cell wall
-motile organisms; can also ingest food particles
(heterotrophs)
Example: Euglena – fresh water green flagellates,
 indicator species of organic pollution
 some are also found in marine waters and mud
B. ANIMAL PROTISTS (PROTOZOANS)
 mostly motile, unicellular, colonial, multi-cellular
organisms
 usually aquatic, part of zooplanktons that fed on
phytoplanktons
 considered heterotrophic, some are holozoic
saprotrophic, parasitic
 classified according to their locomotory organs
pseudopods, cilia, flagella
1. PHYLUM SARCODINA (Rhizopods/amoeboids)
 about 8,000 species
 float or creep about in water
 a thin cell membrane surrounds the protoplasm of the
cell body
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 with protoplasmic extension called…PSEUDOPODIA
OR “FALSE FEET” for movement and capturing the
food (engulf their prey)
 some may cause disease such as Entamoeba
histolytica, a parasite in human intestine that causes
amoebic dysentery
Example: Amoeba
2. PHYLUM CILIOPHORA (ciliates)
 about 5,000 species
 move by means of hairlike processes called “CILIA”
 most are holozoic (engulf whole food)
 divide by transverse binary fission
 retain a more or less permanent shape because of a
(hard covering) known as PELLIOLE
 differ from others by having 2 types of nuclei
the large macronucleus that controls the normal
metabolism of the cell
the
small
micronuclei
concerned
with
reproduction
Example: Paramecium, Balantidium coli
3. PHYLUM SPOROZOA (sporozoans)
 about 2,000 species
 all parasitic with complicated life cycle
 not capable of locomotion (non motile)
 feed on protoplasm and body fluids of their host
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Example: Plasmodium
Plasmodium vivax – causative agent of malaria
from the bite of female Anopheles mosquito
“Anopheles minismus flavirostvis”
- injects sporozoites in the blood of a person,
enters the blood stream, destroys the RBC
- brings chills and high fever
4. PHYLUM ZOOMASTIGINA (zooflagellates)
 about 1,200 species
 move by means of flagella
 unicellular, some are colonial, others are parasitic
 mostly mutualistic or live in symbiotic relationships
with other animals that may cause human diseases
Example:Trichomonas, Trypanosoma, Giardia
RELEVANCE/ SIGNIFICANCE:
 algal protists (algae) supplied food and oxygen to
aquatic animals
 70 species of algae are edible or can be eaten by man
like…
the ULVA (see lettuce), CAVLERPA or (ar – arosep),
CODIUM
 some have industrial uses
- brown alga – algin used in making ice cream
- red alga – carrageenan, agar are used as stabilizer
in food, paints, cosmetics, pharmaceuticals
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 some species are harmful
- Dinoflagellates are the cause of RED TIDE




Animal Protists (protozoans)
important in the hydrosphere
serve as indispensable link in the food chain
some species cause serious diseases in man
- malaria (Plasmodium)
- amoebiasis (Entamoeba)
- Fatal sleeping sickness (Trypanosoma)
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III. KINGDOM FUNGI
 multicellular eukaryotes about 80,000 species
 heterotrophs organisms, cannot produce their own
organic materials, lack chlorophyll
 obtain nutrients from dead organic matter
(decomposers) so they can be (SAPROPHYTES) or
from other living organisms (PARASITIC)
 grow best in moist, warm, organic rich environments
 optimum pH for most species is 5.6
 mostly aerobic
 energy reserve is glycogen
 reproduce by formation of sexual or asexual spores or
by fragmentation of the hypha
 this includes the mushrooms, bracket fungi, bread
mold, yeasts, mildews, slime molds
MORPHOLOGY/ BODY STRUCTURES:
1. Thallus – main body of the fungi
- actively growing vegetative portion
2. Hypha – filamentous or thread like structure that grows
from the body
3. Mycelium – a group of hypha
4. Spores – non- motile structure produce by fungi during
sexual and asexual reproduction
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CLASSIFICATION:
 about 1.5 million species of fungi are in the world
1. PHYLUM BASIDIOMYCOTA (club fungi)
 the most advance group, about 1,500 species
 produce spores on a special structure called the
“Basidium”
Example: mushrooms, bracket fungi, rusts that infect some
trees and smuts that infect corn
2. PHYLUM ZYGOMYCOTA (conjugation fungi)
 the simplest form of fungi, about 1,000 species
 reproduce by conjugation resulting into a zygosphore,
a fungus which attacks fruits
 the most popular species of this group is the
Example: bread mold (Rhizopus)
3. PHYLUM ASCOMYTA (sac fungi)
 the largest division of fungi, about 15,000 species
 asexual reproduction is more common
Example: yeast, blue – green molds, morels and
powdery mildews which attack plants
*yeast are found in decaying fruits, grains and other
food, a little larger than bacteria
 used in making of wine, bread (dough nut)
4. PHYLUM OOMYCOTA (water molds)
 about 500 species
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 parasitize fishes and same food crops
 found in water or moist habitats
 cell wall is made up of cellulose instead of chitin
Example: Saprolegnia – parasitizes fishes
Peronospora – blue mold of tobacco
5. PHYLUM DEUTEROMYCOTA (Imperfect fungi)
 always reproduce asexually by coniodiospores
 no sexual reproduction unlike the other 5 phyla
 include some important fungi/ parasites that causes
athlete’s foot and ringworm
Example: Penicillium – the source of penicillin
Candida – causes yeast infection
6. PHYLUM MYXOMYCOTA (slime molds)
 about 400 species
 resemble giant amoebas because they move over
decaying organic matter by amoeboid movement
 seen on rotting logs, decaying leaves or moist soil
 the thallus of this mold is called “PLASMODIUM”
Example: Dictyostelium, Physarum
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IV. KINGDOM PLANTAE (plants)
 multicellular eukaryotic organisms
 mostly autotrophic (major producer in the world)
 non motile organisms
 over 300,000 species
 with cell wall made up of cellulose substance
 reproduce by sexual or asexual means
 with chlorophyll pigment needed in the process of
photosynthesis
CLASSIFICATION:
I. DIVISION BRYOPHYTA (Bryophytes)
 non vascular plants or lack conducting tissues (no
xylem and phloem)
 the first plants to live on land
 small multicellular plants lack true roots, stems, and
leaves
 mostly terrestrial occurring in moist places, like in
moist soil, rocks, cement fences and walls, tree trunks,
forest floors, banks of streams and others
THREE MAJOR GROUPS:
1. CLASS MUSCI (true mosses)
 about 4 cm. long with tiny, spirally arranged green
leaves
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 grow as a colony forming green mats that cover moist
and shady soil, rocks, cement structure, tree trunks
 the most common or popular mosses in our country is
the Sphagnum or “peat moss” that used as planting
medium for potted plants because it can hold/ absorbs
great amount of water
2. CLASS HEPATICAE (Liver worts)
 with flat, leathery thallus that shaped like the liver
*wort – “herb”
 grows in areas where mosses are found
 green in color about 1 cm. wide
 the most common genera are the Marchantia and
Porella
3. CLASSS ANTHOCEROTAE (hornworts)
 looks like a small, flat, green structure about 2 cm.
wide with numerous lobes that grows adhering to the
ground
 the most common genus is the Anthroceros
II. DIVISION TRACHEOPHYTA (Tracheophytes)
 vascular plants or with conducting tissues (xylem and
phloem)
 the dominant land plants that ranges from herbs,
shrubs and trees
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 generally grows taller and wider than bryophytes
because of the presence of xylem and phloem
 can be seed bearers or non seed bearers
 seed bearers can be flowering (Angiosperm) or non
flowering (Gymnosperm)
 the body is divided into different organs…(the roots,
stems, leaves, flowers)
1. SUBDIVISION PSILOPHYTINA (Psilopsids)
 non seed bearing plant with body axis extending down
ward into the soil
 leaves and roots are absent; usually small plant
Example: Psilotum
2. SUBDIVISION LYCOPHYTINA (Clubmosses)
 non seed bearing, usually small with simple
irregularly arranged leaves
 dominant land plant group in the swamps that covered
the earth about 300 million yrs. Age
Example: Lycopodium, Selaginella
3. SUBDIVISION SPHENOPHYTINA (horse tails)
 non seed bearing, known mostly as fossils
 generally small herbaceous plants
 form a strobilus or cone that resembles a horse tail
Example: Equisetum
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4. SUBDIVISION PTEROPHYTINA (Fern)
 most extensive and numerous of the seedless plants
comprising more than 12,000 species
 the leaves are more broad and more vascularized than
the others
 commonly grown in gardens for their beautiful leaves
Example: ferns
5. SUBDIVISION SPERMATOPHYTINA (seed plants)
 the seedbearing plants with well developed vascular
tissues
 undergo pollination process (cross/ self)
 group into gymnosperm and angiosperm based on
how the seeds are borne
A. GYMNOSPERM (naked seeds) non flowering
 seeds are not surrounded by a mature ovary wall,
(exposed)
 seeds are borne on the surface of cones “cone bearing
plants”
1. CLASS CYCADOPSIDA (cycads)
 dioecious plants with palmlike or fern like form
 produce strobili or cones
 grow in warm climates
 abundant during the age of dinosaurs
 locally known as the “PITOGO” or sago palm
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2. CLASS GINKGOPSIDA (ginkgoes)
 dioecious plants with tree habit
 have strap – shaped or fan – shaped leaves with catkin
like strobili
 common as an urban tree resistance to air pollution
 survived today as a single specie , the ginkgo or the
“maiden hair tree”
3. CLASS CONIFEROPSIDA (conifers)
 monoecious plants most of which are trees
 with typical scale like or needle like leaves that are
usually evergreen (pine tree)
 the most conspicuous of the gymnosperm especially in
colder climates
 most common local species of pines are Pinus
insularis and Pinus merkusli with both male and
female cones in the same tree
4. CLASS GNETOPSIDA (gnetopsids)
 mostly large and coarse plants, frequently with thick
unbranched stem bearing crown of palm like leaves
 tropical dessert plants; extinct
Example: Gnetum, Ephedra, Welwitschia
B. ANGIOSPERMS (flowering plants)
 constitute the dominant terrestrial vegetations
 close to 219,300 species of flowering plants
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 with seeds contained or enclosed within the ovary of
the flower
 includes a great variety of shrubs, trees and
herbaceous plants
 can grow as annuals, biennials and perennials
CLASS MAGNOLIOPSIDA
SUBCLASS MONOCOTYLEDONEAE (monocot)
 plants with only one cotyledon or (seed leaves)
Example: rice, corn, lilies
SUBCLASS DICOTYLEDONEAE (dicot)
 Plants with two cotyledons
Example: fruit bearing trees like mango, avocado,santol
flowers like rose, gumamela
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V. KINGDOM ANIMALIA
 all animals are many-celled
 the cells are differentiated to form specialized tissues
 tissues are usually grouped to form organs and the
organs to organ systems
 most animal cells have a nucleus and organelles such
as mitochondria, golgi bodies, lysosomes and
robosomes
 animal cells are bounded by a plasma membrane
 they are not rigid like plant cells. Animals are
heterotrophic
 they feed on other organisms
 most animals are motile and can move from place to
place
 all animals are capable of sexual reproduction
although some reproduce asexually
1. Phylum Porifera (Sponges)
 Some sponges are the simplest of the animals.
 The body is perforated with minute pores called ostia
for the entrance of water into a central cavity, the
spongocoel.
 The larger openings, the oscular, are for the exit of
water.
 Sponges have no organs, only tissues.
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 Digestion takes place within the cell called
intercellular digestion.
 Flagellated cells circulate the water in the
spongocoel.
 The skeleton is in the form of microscopic spicules or
a network of sponging or both.
 The sponge is attached to the sea bottom or to rocks
by means of a stolon.
a. Class Calcarea
 Calcareous sponges
 Spicules limy (CaCO3). 1-, 3- or 4-rayed; body
surface bristly; marine in shallow waters.
Example: Grantia
b. Class Hexactinellida.
 Glass sponges. Spicules siliceous, 6-rayed; marine,
at 300 feet or deeper.
Example: Venus’ flower basket.
c. Class Demospongiae.
 Skeleton siliceous; mostly marine.
Example: bath sponge.
d. Class Sclerospongiae.
 Coralline sponges
 Massive skeleton of calcium carbonate
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Example: Merlia.
2. Phylum Coelenterata (Cnidaria) Coelenterates
 Most coelenterates are colorful so that most of the
time they are referred to as “flower animals”.
 These are the animals that fascinate scuba divers for
they abound in the sea bottom.
 The body of the coelenterates is radially symmetrical.
 The digestive tube is in the form of a hollow,
gastrovascular cavity.
 There is no anus.
 Hence the digestive tube is incomplete.
 Their mouth is surrounded with tentacles which are
provided with stinging cells or nematocysts.
a. Class Hydrozoa. Hydroids.
 Mouth opens directly into a digestive cavity
that lacks partitions; hydroid stage usually in
colonies; medusa with velum.
Example: Hydra (freshwater polyp)
b. Class Scyphozoa. Jellyfishes.
 Small to large medusae, chiefly of gelatinous
mesoglae, and of bell or umbrella shape,
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margined with tentacles; polyp stage minute or
none
Example: Acrometoides (a common specimen found
in Manila bay)
c. Class Anthozoa. Sea anemones, corals, etc.
 All polyps (no medusae); a flat oral disk with
tentacles; digestive cavity divided by radial
partitions.
Examples: sea anemone, sea fan, staghorn coral,
organ pipe coral and black coral.
3. Phylum Platyhelminthes (Flatworms)
 These are the unsegmented worms.
 The body is dorsoventrally flattened and
bilaterally symmetrical.
 The digestive tube is incomplete because there is
no anus.
 Flatworms are either free-living or parasitic.
 They are usually hemaproditic.
a. Class Turbellaria (Free-living flatworms)
 their body is ribbonlike to dislike.
 they have no hooks or suckers.
 they are either marine, freshwater or terrestrial.
Example: Planaria
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b. Class Trematoda (Flukes)
 their body is often leaflike, with thick cuticle and
no cilia.
 some have ventral suckers or hooks or both.
 all are parasitic.
Example: Fasciola (liver fluke)
c. Class Cestiodea. (Tapeworms)
 their body is flat, narrow, elongate, comprising of
a scolex.
 they make use of suckers or hooks or both for
attachments.
 all are parasitic.
Example: Taenia (pork tapeworm)
4. Phylum Nematoda. (Roundworms)
 their body is cylindrical.
 there are about 10,000 species of these worms.
 some feed on decaying matter and are therefore
scavengers.
 most species are parasitic on plants and animals
 a few are free-living.
 a typical example is Ascaris lumbricoides,
eelworm of man.
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 the sexes are separate.
 the female looks differently from the male and are
therefore sexually dimorphic.
 the body is slender and cylindrical, tapering at
both ends.
 it is covered by a smooth, tough and elastic
cuticle, bearing minute striations.
 the female is larger than the male.
 turbatrix aceti, vinegarell, is the most familiar
example of a free-living nematode.
 this is seen as the minute organism on the surface
of naturally fermented vinegar.
 these are non-pathogenic forms.
 parasitic forms include hookworms, whipworms
and pinworms.
5. Phylum Rotifera (Wheel Animalcules)
 They are called wheel animalcules because of two
groups of cilia which beat the water like a pair of
spinning wheels.
 They are microscopic forms found in freshwater
ponds, streams, muddy ditches and street gutters.
 They feed on unicellular forms with the use of the
wheel organ.
Example: Hydatina.
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6. Phylum Bryozoa (Moss Animals)
 They are called moss animals because they are
similar in appearance to bryophytes.
 All bryozoans are aquatic and most are marine.
 They are colonial most are attached or sessile.
 The body is cylindrical with the mouth
surrounded by ciliated tentacles. The digestive
system is complete.
Example: Bugula.
7. Phylum Mollusca (Mollusks)
 Their body is radially symmetrical, usually no
segmentation.
 Their soft bodies are covered by a mantle that
usually secretes a limy shell.
 They usually have an anterior head and a ventral
muscular foot for locomotion.
 The digestive tract is complete.
 Sexes are usually separate.
 Some are found in saltwater, others in freshwater
and some on land.
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a. Class Polyplacophora. Chitons
 Their body is usually elliptical.
 They have shells made up of eight plates.
 They are marine type.
Example: Chiton.
b. Class Scaphopoda. Tooth shells
 They have a tubular shell open at both ends and
shaped like an elephant’s tusks.
Example: Dentalium.
c. Class Gastropoda. Univalve mollusks.
 They are known as stomach-footed mollusks.
 The foot is long and flat and lies under the belly.
 It is used for creeping, hence, the name stomachfooted or gastropods.
 They are also called univalves of the presence of
single shell which may be spiral or not.
 The heads is distinct, with one or two pairs of
tentacles.
Example: snail, slug, abalo and cowry.
d. Class Bivalvia. Bivalve mollusks.
 They are known as the hatchet-footed mollusks.
 The foot is wedge-shaped and is used for digging.
 The shell is made up of two valves, hence the
name, bivalves.
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 They have no head or jaws.
Examples: clam, mussel and oyster.
e. Class Cephalopoda. Squids,octopus, etc.
 They are known as the head-footed mollusks
because the foot is in the form of tentacles attached
to the head, hence the name head-footed.
 The foot is used for food-getting.
 Eyes are larger and prominent.
 The shell is internal as in squids or external as in
the nautili.
Examples: squid, octopus (devilfish) and nautilus.
8. Phylum Annelida (Segmented Worms)
 There are about 10,000 anneloids.
 The unique feature of this group is segmentation.
 The body is divided into similar ringlike segments
or somites.
 They have a complete digestive tract.
 They are found in freshwater, and in moist and
damp places, in seashores or in burrows.
a. Class Polychaeta. Sandworms, tubeworms, etc.
 Segmentation is conspicuous, with many somites
having lateral projections that bear numerous
setae.
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 The head is evident, with tentacles. Sexes are
usually separate. They are chiefly marine.
Example: clamworm.
b. Class Oligochaeta. Earthworms, etc.
 Segmentation is also conspicuous.
 They have no head or parapodia.
 Their setae are usually few per somite.
 They are found in freshwaters and moist soil.
Example: Pheretima benguetensis (common local
earthworm).
c. Class Hirudinea. Leeches.
 Their bodies are flat.
 The somites are inconspicuous, each is divided
internally into several annuli.
 They have no setae or parapodia.
 The first and last body segments are modified to
form suckers used for locomotion and attachment.
Example: Hirudo (leech)
9. Phylum Arthropoda(Artropods)
 This is the largest of all phyla.
 They are found in almost any environment-on
land, underground, in water, on plants, on animals
and inside animals.
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 The anthropods are joint-footed with numerous
paired appendages.
 The body is covered by a chitinous exoskeleton.
 Their digestive tract is complete.
 Sexes are usually separate.
a. Class Merostomata.
 The cephalothorax broadly joined to abdomen on
which are five or six pairs of appendages.
 They are aquatic type.
Example: horseshoe crab
b. Class Arachnida. Arachnids.
 Their abdomen lacks locomotor appendages.
 They are usually terestial.
Examples: tick, scorpion, head louse, spider, and
itch mite.
c. Class Crustacea. Crustaceans.
 They have two pairs of antennae, one pair of jaws,
and two pair of maxillae.
 The body is divided into a cephalothorax and
abdomen.
 The cephalothorax is formed by the fusion of the
head and thorax.
 Most of them are aquatic.
166
Examples: crayfishes, lobster, crab, shrimp and
prawn.
d. Class Insecta. Insects.
 These animals have distinct head, thorax and
abdomen.
 The thorax typically with three pairs of legs and
two pairs of wings.
 They are mainly terrestrial.
Examples: grasshopper, fly, butterfly and mosquito.
e. Class Chilophoda. Centipedes.
 Their body is long, flattened and has 15 to 181
somites, each with a pair of legs.
 They have one long pair of antennae.
 Centipedes are predators.
 They are terrestrial.
Example: Scolopendra (centipede)
f. Class Diplopoda. Millipedes.
 Their body is cylindrical and not flattened.
 The body is divided into a head, thorax and
abdomen.
 The abdomen has 9 to more than 100 double
somites, each with pairs of legs.
 They are terrestrial.
Example: Julus (millipede)
167
10. Phylum Echinodermata (Echinoderms)
 The body of the echinoderms is radially
symmetrical and has no segmentation.
 Characteristic of the group is the presence of spines
that are either minute or large covering of the body.
 The body is supported by a skeleton of bony plates.
 Another unique feature of the group is watervascular system of circulation.
 Water, not blood, is issued for circulation.
a. Class Crinoidea.
 Sea lilies, feather stars.
 They are flower like.
 The body is small and cup-shaped, which is called
calyx.
 Attached to it are five flexible arms.
 Each arm branches into two, each bearing slender
lateral pinnules.
 Thus, the arms resemble feathers.
Example: Antedon.
b. Class Asteroidea.
 Starfishes or sea stars.
 Their body is star-shaped or pentagonal with five
two fifty arms or rays not sharply distinct from
central disk.
168
 Their skeleton is flexible, usually with short
spines.
Example: Asterias
c. Class Ophiuroidea.
 Brittle stars.
 They have five long, segmented arms that move
like snakes, hence, they are called snake star.
 The arms easily break when handled, hence, the
name brittle star.
 It has great power of regeneration, the ability to
replace lost parts.
Example: Ophiura (brittle star)
d. Class Echinoidea.
 Sea urchins, sand dollars.
 Their body may be rounded or ovoid; some are
flattened, others are globular.
 They have no projecting arms.
 The body is covered with small or large spines.
Example:
Strongylocentrotus
(sea
urchin);
Dendraster (sand dollar)
e. Class Holothuroidea.
 Sea cucumbers.
 Their body is bilaterally symmetrical.
 They have no arms.
169
 The mouth is on one end surrounded by retractile
tentacles.
 The body is elongated or wormlike.
Example: Holothuria
11. Phylum Chordata (Chordates)
 There are three unique characteristics of this
phylum:
 they have notochord
 gill slits
 hollow nerve chord.
Protochordates
 The protochordates are the invertebrate chordates or
chordates without vertebral column.
 They look more like primitive invertebrates rather
than chordates.
 However, they share the three unique
characteristics of chordates, thus suggesting a
biological relationship or kinship with the
chordates.
Example: Amphioxus (lancelet)
Vertebrate Chordates
 There are about 49,000 species of vertebrates
inhabiting the seas, freshwater, and land.
170
 Of these, 30,000 species are fishes, the others are
terrestrial forms.
 However, the amphibians, some reptiles and some
mammals share the waters with the fishes.
a. Class Cyclostomata. Lampreys.
 Their body is cylindrical, slender and with median
fins only.
 Their mouth is always open because they have no
jaws.
 They are called cyclostomes (circular mouth) or
jawless vertebrates.
Example: Petromyzon (lamprey)
b. Class Chondrichthyes. Cartilaginous fishes.
 These fishes have skeletons of cartilage instead of
bone.
 All species breathe through their gills.
 The gill slits are exposed and seen at the sides of
the head.
 The skin is covered with placoid scales.
Examples: Squalus(shark);Raja (ray)
c. Class Osteichthyes. Bony fishes.
 These fishes have skeletons made chiefly of bone.
 All species breathe through their gills.
171
 The gill slits are covered by an operculum or gill
cover.
 The scales are usually cycloid and large.
Examples: salmon, milkfish and lungfishes
d. Class Amphibia. Amphibians.
 Most amphibians live partly on land and partly in
water.
 As a result, they have legs instead of fins and
lungs instead of gills in the adult.
 However, their larvae are aquatic and breathe
through the gills.
Examples: frogs, toads, salamanders and mud
puppies
e. Class Reptilia. Reptiles.
 These animals have dry skin covered with horny
scales (hardened skin).
 They breathe through their lungs.
 Most of them are terrestrial and only a few are
aquatic.
 They lay large eggs covered by a soft shell.
Examples: tuatara, lizards, snakes, crocodile and
alligator
172
f.Class Aves. Birds.
 Birds are the only group of vertebrates (excluding
bats) capable of true flight.
 This is the only group with feathers.
 They breathe through the lungs.
 They lay eggs covered by a hard shell.
 Birds are warm-blooded or homeothermous.
 Most of them are terrestrial but some are aquatic.
 Some birds are unable to fly like the ostriches.
Examples: duck, crow, and sparrow
g. Class Mammalia. Mammals.
 This is the only group of vertebrates with hair.
 They gave birth to their young alive.
 They nurse their young with milk coming from
their mammary glands.
 They are homeothermous or warm-blooded.
Examples: man, kangaroo, horse, pig, cat, dog, cow,
whale, bat, rabbit, fox, monkey, bear and others.
173
ECOSYSTEMS
DEFINITION OF TERMS
 Ecology (Greek, oikos, house or home) – the study
of the interactions of organisms among themselves
and with the physical environment
 Population – all members of the same species
inhabiting a particular area
 Community – all the populations found in a
particular area
 Ecosystem – community and its physical
environment, characterized by a flow of energy and
a cycle of inorganic nutrients
 Biosphere – region of the earth (atmosphere,
hydrosphere, lithosphere) where organisms exist
 Succession – progressive change in plant and
animal life of an area
 Habitat – place where an organism lives and able to
survive and reproduce
 Biome – a natural unit of living and non – living
components that interact to form a stable system in
which the exchange of materials follow a circular
path
 Niche – functional role and position of an organism
in the ecosystem
174
 Pollution – any contamination of the environment;
any process by which humans destroy the
environment
THE ECOSYSTEM
Components
Abiotic Components
 the non – living component
 the physical environment
 includes soil, water, light, inorganic nutrients, and
weather conditions
Biotic Components
 the living components
 composed of a habitat and a niche
Different Roles (niche) of the Biotic Components
Producers
 the autotrophic organisms capable of producing their
own food;
 could be chemoautotrophs (bacteria), obtaining energy
by oxidizing inorganic compounds to synthesize
carbohydrates, or a photoautotrophs (plants),
obtaining energy from light to synthesize
carbohydrates
175
Consumers
 the heterotrophic organisms that eat available food
 classified into three groups:
1. herbivores (primary consumers) feed directly on
green plants
2. carnivores (secondary or tertiary consumers) feed
on other animals
3. omnivores feed on both plants and animals
Decomposers
 the heterotrophic organisms that break down detritus,
non – living organic matter, to inorganic matter, to be
used again by the producers
AQUATIC ECOSYSTEM
Classification of Organisms Present in Aquatic Ecosystem
1. benthos, resting or living at the bottom
2. periphyton, attached or clinging on stems or leaves
of rooted plants or other surfaces projecting above the
bottom
3. plankton, floating, dependent on the current
4. nektons, swimming can navigate at will
5. neuston, resting or swimming on the surface
Freshwater Ecosystems
 occupy relatively small portion of earth’s surface
176
 the most convenient and cheapest source of water for
domestic and industrial needs
 the study of freshwater habitats is called limnology
Types of Freshwater Ecosystems
1. Lentic or standing water – ponds and lakes
Subdivided into three major zones:
a. littoral zone, shallow water region with light
penetration up to the bottom
b. limnetic zone, open water zone up to the depth
of effective light penetration
2. Lotic or running water – rivers and streams
Subdivided into two major zones:
a. Rapid zone, shallow water where velocity of
current is great enough to keep the bottom clear
of silt and other loose materials providing a firm
substrate.
b. pool zone, deeper water where velocity of
current is reduced and silt and other loose
materials settle to the bottom providing a soft
substrate
Marine Ecosystem (Ocean)
 occupy 70% of the earth’s surface
 the great reservoir of living things and nutrients
 the study of marine habitat is called oceanography
177
Divisions of the Ocean
1. pelagic division includes the open sea
a. neritic province, shallow water above the
continental shelf, with more nutrients and
organisms because sunlight penetrates the waters
up to the bottom
Subdivided into three zones:
 supratidal (above the high tide mark)
 intertidal (between high and low tide)
 subtidal (below the low tide mark)
b. oceanic province, the region of the open sea
beyond the continental shelf, above the oceanic
basins
Subdivided into four zones:
 euphotic zone, (depth up to 120 m, upper part
of the ocean into which light can penetrate)
 bathyal zone (depth up to 3,000 m, lower part
of the ocean in complete darkness)
 abyssal zone (depth up to 4,000 m)
 hadal zone (depth betond 4,000 m)
2. benthic division includes the depths of the sea
Subdivided into three zones:
178
a. continental shelf in the sublittoral shelf, the floor of
the neritic province
b. continental slope in the bathyal zone, a sudden drop
of the ocean floor from the continental shelf up to the
abyssal plain
c. abyssal plain in the abyssal zone, the ocean floor of
the abyssal zone, interrupted by many underwater
mountain chains called oceanic ridges
TERRESTIAL ECOSYSTEM
 the most variable in terms of time and geography
 has the largest plant biomass
Types of terrestrial biomes
Tundra
-located nearest to the polar region
-vegetation includes lichens, mosses, grasses and lowgrowing shrubs
-few animals adapted to cool temperature live in the
tundra, polar bears, caribou, and musk ox; during
summer, insects and birds migrate the biome
Taiga
-located just below the tundra extending in a broad
belt across northern Eurasia and North America
-composed of coniferous forest dominated by conebearing trees such as spruce, fir and pine
179
-birds, bears, deer, moose, beavers, wolves and even
mountain lion could be found
Temperate Deciduous Forest
-located south of the taiga in eastern North America,
eastern Asia and much of Europe
-with moderate climate and relative high rainfall
-dominated by deciduous trees, oak, beech and maple
-amphibians and reptiles are found, together with
some other vertebrates as squirrels, rabbits, foxes, deer
and bears
Tropical Rain Forest
-located near the equator
-considered to be the richest biome in terms of number
and abundance of species
-has a complex structure, with many levels of life,
from simplest bryophytes and epiphytes to woody
vines and giant trees
-insects, amphibians, reptile birds, and mammals are
well represented
-characteristic of Philippine forest
Grassland (Savanna)
-located in regions where a relatively cool dry season
is followed by a hot, rainy one
180
-dominated by grasses that can adapt to changing
temperature and can tolerate high degree of grazing,
flooding, drought and sometimes fire
-supports large group of grazers (zebras and
wildebeests)
and
browsers(giraffes),
and
predators(cheetahs and lions)
Deserts
-located at about 30o, in Northern and Southern
hemispheres
-support organisms adapted to arid conditions
-plants are succulents, or shrubs with woody stems
and small leaves
-animals require little water or are adapted in storing
water such as kangaroo rat, roadrunner, insects, lizards
and snakes
SPECIES INTERACTIONS
Symbiotic Relationships
 refers to interactions in which there is a close
relationship between members of two populations
Parasitism
-one species(parasite) benefits in terms of growth and
reproduction to the harm of the other species(host)
-tapeworm(parasite) and cow or pig(hosts), mites and
dog
181
Commensalism
-one species is benefited and the other is neither
harmed nor benefited
-sucker fish and shark, crane and carabao
Mutualism
-both species benefit in terms of growth and
reproduction;
-lichens(fungi and algae), termites and protest
Predation
 one species(predator) uses the other(prey) as a food
source
 ther must be an act of killing
 lioness(predator) and zebra(prey), eagle and chicken
SUMMARY
 Ecology deals with the study of interrelationships
between living organisms and the non-living factors in
the environment, which may be affecting them.
 An ecosystem is an interacting system between the
community and its abiotic environment.
 Different interactions occur in the biotic and abiotic
components of the community.
182
VIRUSES
 not considered as true organism due to inability to
perform metabolic activities
--no metabolic machinery of their own
--lack enzyme systems
--can’t generate ATP
--can’t reproduce themselves
 called “borderline forms” between living and nonliving things
 generally smaller than the smallest bacteria (less than
200 µm in diameter)
 can be purified and crystallized or stored
 the viral crystals are still infectious when given
opportunity to invade the host cells
 considered as obligate intracellular parasites (can
multiply outside a living cell)
 can infect all sorts of cell but very specific
--bacteriophages infect only bacteria
--tobacco mosaic virus only in plants
--rabies virus only in mammals
--human immunodeficiency virus (HIV) only in blood
cells
--polio virus only in spinal nerve cells
--hepatitis virus only in liver cells
183
DISCOVERY OF VIRUS
 1884, Louis Pasteur, French Chemist suggested that
something smaller than a bacterium was the cause of
rabies and gave the name “virus” to it from Latin
meaning poison
 1892, Dmitri Ivanowsky, Russian biologist studied
tobacco mosaic disease and concluded that the
disease-causing agent was smaller than any known
bacteria and concluded that it was a toxin rather than a
microorganism
VIRAL STRUCTURE
 Outer capsid
--composed of protein-subunits
--maybe surrounded by an outer membranous
envelope
 Inner core of nucleic acid
--either DNA or RNA but not both
--may contain various proteins (enzymes) needed to
produce viral DNA or RNA
TYPES OF VIRUS
 As to host cells
1. Plant viruses – live only in the cells of seed plant,
especially flowering plants
2. Human and Animal viruses – live only in human
and animal cells
184
3. Bacteriophages – invade only bacterial cells
 As Agents of diseases
1. Virulent – can cause a disease to the host
immediately
2. Temperature – does not cause a disease to the host
immediately
 As to the type of Nucleic Acid
1. DNA VIRUS – contains DNA as the genetic
material, can cause sore throat, warts, herpes, chicken
fox, fever, small pox, measles
2. RNA VIRUS – contains RNA as the genetic
material, cam cause polio, hepatitis, rabies, common
cold, influenza, pneumonia, encephalitis
3. RETROVIRUS – contains an enzyme transcriptase,
that makes DNA from RNA, the DNA formed makes
new RNA which in turn makes new protein to be part
of a new virus
e.g. HIV VIRUS
AIDS (Acquired Immune Deficiency Syndrome)
 Caused by retrovirus HIV (Human Immunodeficiency
Virus)
 The HIV invades and destroys the body’s white blood
cells, particularly (D4 lymphocytes or helper T-cells
 Could be found in…
-blood and semen (high concentration)
185
-vaginal secretion }
-saliva, tears, urine} in trace concentration
-breast milk }
 sexually transmitted disease that may be developed
after 7 to 11 years of HIV infection
TRANSMISSION OF HIV
 exchange of bodily fluids during sexual intercourse or
oral genital contact
 sharing of blood contaminated needles by IV drug
users (intravenous)
 transfusion of infected blood
 prenatal transmission from an infected woman to her
fetus or infant
SARS (Severe Acute Respiratory Syndrome)
 a condition of unknown etiology that has been
described in patients in Asia, North America and
Europe
 a respiratory illness classified as a typical pneumonia
or an infection of the respiratory tract that is caused by
the corona virus, a virus that causes common colds in
human and more serious illness among animals
186
MODE OF TRANSMISSION
 the main way that SARS is spread is through droplet
transmission
 such droplets maybe produced when someone with
SARS sneezes or coughs
 SARS may also spread through contaminated objects
 Airborne transmission is most likely possible
ORGANS AFFECTED
 inflation of the lungs and retention of fluid in the
lungs
 tissue damage to the heart muscle and other organs
like liver
187
EVOLUTION:
I.HISTORY OF THE EARTH (MORE THAN 5
BILLION YEARS OLD)
 DIVIDED INTO THREE ERAS
A. PALEOZOIC (ANCIENT LIFE)
-the layers of the rocks and the kind of organisms
formed during this time were preserved and recorded
*EARLY PALEOZOIC ERA
-the fishes were the first vertebrates to appear (no jaws
and no paired fins)
*MIDDLE PALEOZOIC ERA
-Fishes with jaws and paired fins appeared
*LATE PALEOZOIC ERA
-Amphibians appeared along with some fishes which
had fins with lobes that enabled them to propel
themselves on land
B. MESOZOIC ERA (MIDDLE LIFE)
-considered as the great age of the reptiles
*EARLY MESOZOIC ERA
-dinosuars appeared
*MIDDLE MESOZOIC ERA
-birds appeared
*LATE MESOZOIC ERA
-dinosuars start to disappear
188
-as the great reptiles become extinct, the birds took
over
C. CENOZOIC (RECENT LIFE)
-about seven million years ago, the first mammals
appeared
*EARLY CENOZOIC ERA
-during this period, the horse was the first mammal
appeared which was only as big as a dog
-it had several toes on the foot
-gradually became larger, legs became longer and
only one toe remained on each foot
*some mammals of this era have grown in size
tremendously
like
rhinoceros,
elephants,
hippopotamus and others
*some giant mammals disappeared before theend of
the ice ages about 10 million years ago
*LATE CENOZOIC ERA
- the process of evolution showed that several
organisms change new forms, some are lost or
become extinct
GEOLOGICAL TIMETABLE:
Through the ages, the nature has left records of time
and change.
189
“GEOLOGICAL CHANGES”
-the layers of the earth’s crust were formed by
sediment that settle at the bottom of oceans, seas, lakes or
other bodies of water
-here, the layers are cemented together by chemicals
in the water and pressures of overlaying layers forming
rock called “sedimentary rocks”
-new layers settle above older layers leaving a
timetable in rock
-the exploration of these layers of sedimentary rocks
from more recent layer near the surface to the ancient layer
deep into the earth is a journey through million of years of
GEOLOGICAL TIME.
CONCEPTS OF EVOLUTION:
 The characteristics of living things change with time.
Change in the characteristics of population over the
course of many generations
 The change is directed by Natural Selection process.
Changes are in the Genetic make up of the population
EVIDENCES OF EVOLUTION
 FOSSIL – a record of the history of life that shows
that organisms have changed over time
 BIOGEOGRAPHY – the study of the distribution of
life form shows that organisms evolve in one locale
and then spread to other regions
190
 COMPARATIVE ANATOMY – related organisms
share a unity of plan
 COMPARATIVE EMBRYOLOGY – related
organisms develop similarly
 COMPARATIVE BIOCHEMISTRY - almost all
living things use the same basic biochemical
molecules, including DNA, ATP and many identical
enzymes
LAMARCK’S THEORY OF EVOLUTION
-JEAN BAPTISTE de LAMARCK (1744-1829)
proposed three theories about evolution
1. THEORY OF NEED
-the production of a new organism or part of the
organism arises from the need for it.
2. THEORY OF USE AND DISUSE
- continued use of an organ strengthens it and
continued disuse of an organ weakens it until it disappears
3. THEORY OF INHERITANCE OF ACQUIRED
CHARACTERS
-characteristics that have been acquired or changed
during the lifetime of the organisms is transmitted to the
offspring
191
DARWINISM (Charles Darwin 1809-1882)
-proposed and formulated the process of
EVOLUTION in his book “The Origin of Species” by
means of natural selection.
THEORY OF NATURAL SELECTION
-According to Darwin, the chief factors responsible
for the development of new species from common ancestry
are as follows
1. OVERPRODUCTION – all organisms produce more
offspring that can actually survive
2. STRUGGLE FOR EXISTENCE - because of
overproduction, there is a constant struggle for existence
among individuals
3. VARIATION AMONG INDIVIDUALS – plant
breeders choose plants that are disease resistant or control
the size or characteristics of fruits by experimentation
(cross fertilization)
4. SURVIVAL OF THE FITTEST – slight variations in
speed or instinct can mean survival for the fittest
individual. In this way, nature selects the characteristics of
a certain population by favoring even the slightest
variation
5. TRANSMISSION OF THE VARIATION TO THE
OFFSPRING – Darwin believed that these changes in the
individual brought about by nature giving him a special
fitness will automatically be transmitted to his offsprings
as the type selected by nature to continue their species
192
RESULTS OF NATURAL SELECTION:
 Advance body organization and improve species
 Preserve
and
accumulate
small-inherited
modifications that are profitable for the species
 The favored form increases in number and generally
the least favored decreases and become rare
ORGANIC EVOLUTION
 defined as a change in genetics of a population over
time (generations)
 a population refers to all individuals of the same
species living in a defined area at the same time
 can be studied at two different levels
1. MICRO EVOLUTION
-small scale genetic changes within populations
-occurs through several mechanism
2. MACRO EVOLUTION
-evolution within population
-can also occur through several other mech.
Ex. “speciation”- refers to the formation of new species; it
occurs when one ancestral species evolves into more than
one descendant species
-brought about by variation, migration, environment
change, selection and isolation
193
CONVERGENCE AND DIVERGENCE
*CONVERGENT EVOLUTION / CONVERGENCE
 Two or more unrelated groups that adapt themselves
to the same environment may show some common
characteristics
 A condition nearly reverse to adaptive variation
Ex. Fishes, whales and sea lions are all adapted to life
in water
*DIVERGENT EVOLUTION/DIVERGENCE
 Evolving of different characteristics in closely related
groups
 An adaptive variation form of evolution
Ex. A mammal like ancestor gave rise to bats, rabbits,
elephant, whales
194
THE DIGESTIVE GLANDS
Several Digestive glands aid in the breakdown of
various organic substances in food. These are given in
the table below indicating the enzyme they secrete and
the action of each particular enzyme.
REGION/GLANDS
Mouth
 Salivary glands
 submaxillary
 sublingual
 parotid
Pharynx
Esophagus
Stomach
 H cells
 chief cells
DIGESTIVE
ENZYME(S)
salivary
amylase
(ptyalin)
MODE OF
ACTION
Hydrolyzes starches
to polysaccharides
then to disaccharides
maltose
none
none
HCl
mucin
pepsin
195
 lowers ph
 increases acidity
of stomach
 lubricates
the
food
 splits proteins to
proteases/pepto
nes
Small Intestine
 pancreas




trypsin
chymotrypsin
carboxypeptides
amylase
 breaks down
polysaccharid
es into a
mixture
of
glucose
&
maltose
 breaks down
fats
to
glycerol
&
fatty acids
 lipase
 liver/gall
bladder
 mucosal
lining
Large intestine
Cloaca/Anus
 (breakdown
proteins
&
polypeptides
to
amino
acids)
 bile
emulsifier,
enzyme)
(an
not
 bicarbonate
enzyme)
(not
None
none
196
 facilitate
digestion
fats
 neutralizes
acid
of
197