Introduction and Tissues
Human Anatomy
BIOL 1010
Liston Campus
What is Anatomy?
Anatomy (= morphology): study of body’s structure
Physiology: study of body’s function
Structure reflects Function!!!
Branches of Anatomy





Gross: Large structures
Surface: Landmarks
Histology: Cells and Tissues
Developmental: Structures change through life
Embryology: Structures form and develop before birth
Hierarchy of Structural
Organization
Each of these build upon one another
to make up the next level:
Chemical level
Cellular
Tissue
Organ
Organ system
Organism
Hierarchy of Structural
Organization
Chemical level


Atoms combine to make molecules
4 macromolecules in the body
 Carbohydrates
 Lipids
 Proteins
 Nucleic acids
Hierarchy of Structural
Organization
Cellular

Made up of cells and cellular organelles
(molecules)
 Cells can be eukaryotic or prokaryotic
 Organelles are structures within cells that
perform dedicated functions (“small organs”)
http://cmweb.pvschools.net/~bbecke/newell/Cells.html
Hierarchy of Structural
Organization
Tissue


Collection of cells that work together to
perform a specialized function
4 basic types of tissue in the human body:
 Epithelium
 Connective tissue
 Muscle tissue
 Nervous tissue
www.emc.maricopa.edu
Hierarchy of Structural
Organization
Organ

Made up of tissue
 Heart
 Brain
 Liver
 Pancreas, etc……
Pg 181
Hierarchy of Structural
Organization
Organ system (11)

Made up of a group of related organs that
work together











Integumentary
Skeletal
Muscular
Nervous
Endocrine
Cardiovascular
Lymphatic
Respiratory
Digestive
Urinary
Reproductive
Circulatory
Pg 341
Urinary System
Hierarchy of Structural
Organization
Organism



An individual human, animal, plant, etc……
Made up all of the organ systems
Work together to sustain life
Anatomical Directions
Anatomical position
Regions

Axial vs. Appendicular
Anatomical Directions-It’s all Relative!





Anterior (ventral) vs. Posterior (dorsal)
Medial vs. Lateral
Superior (cranial) vs. Inferior (caudal)
Superficial vs. Deep
Proximal vs. Distal
Anatomical Planes



Frontal = Coronal
Transverse = Horizontal = Cross Section
Sagittal
Pg 5
Reference Point
Anterior – (ventral)
Closer to the front surface of
the body
Posterior – (dorsal)
Closer to the rear surface
of the body
Frontal Plane
Medial –
Lying closer to the midline
Lateral –
Lying further away from the
midline
Sagittal Plane
Superior – (cranial)
Closer to the head in relation to
the entire body
(More General)
Inferior – (caudal)
Away from the head or
towards the lower part of
the body
Horizontal Plane
Superficial –
Towards the surface
Deep –
Away from the surface
Surface of body or
organ
Proximal –
Closer to the origin of a body
part
(More Specific)
Distal –
Further away from the
origin of a body part
Origin of a structure
4 Types of Tissue
1)Epithelium
2)Connective
3)Muscle
4)Nervous
Tissues:
groups of cells closely associated that
have a similar structure and perform a related function
Four types of tissue




Epithelial = covering/lining
Connective = support
Muscle = movement
Nervous = control
Most organs contain all 4 types
Tissue has non-living extracellular
material between its cells
EPITHELIAL TISSUE:
sheets of
cells cover a surface or line a cavity
Functions
Protection
 Secretion
 Absorption
 Ion Transport

Characteristics of Epithelium
Cellularity

Composed of cells
Specialized contacts

Joined by cell junctions
Polarity

Apical vs. Basal surfaces differ
Supported by connective tissue
Avascular
Innervated
Highly regenerative
Classification of Epithelium-based
on number of layers and cell shape
Layers


Simple
Stratified
 Stratified layers characterized by shape of apical layer

Psuedostratified
Shapes




Squamous
Cuboidal
Columnar
Transitional
Types of Epithelium
Simple squamous (1 layer)

Lungs, blood vessels, ventral body cavity
Simple cuboidal

Kidney tubules, glands
Simple columnar

Stomach, intestines
Pseudostratified columnar

Respiratory passages (ciliated version)
Stratified squamous (>1 layer)




Epidermis, mouth, esophagus, vagina
Named so according to apical cell shape
Regenerate from below
Deep layers cuboidal and columnar
Transitional (not shown)


Thins when stretches
Hollow urinary organs
All histology pictures property of BIOL 1010 Lab
Special Epithelium
Endothelium


Simple squamous epithelium that lines vessels
e.g. lymphatic & blood vessel
Mesothelium


Simple squamous epithelium that forms the lining
of body cavities
e.g. pleura, pericardium, peritoneum
Features of Apical Surface of
Epithelium
Microvilli: (ex) in small intestine
 Finger-like extensions of the plasma membrane

of apical epithelial cell
Increase surface area for absorption
Cilia:


(ex) respiratory tubes
Whip-like, motile extension of plasma membrane
Moves mucus, etc. over epithelial surface 1-way
Features of Lateral Surface of
Epithelium
Cells are connected to neighboring cells via:


Contour of cells-wavy contour fits together
Cell Junctions (3 common)
 Desmosomes
 Proteins hold cells together to maintain integrity of tissue
 Tight Junctions

Plasma membrane of adjacent cells fuse, nothing passes
 Gap junction

Proteins allow small molecules to pass through
Features of the Basal Surface
of Epithelium
Basement membrane



Sheet between the epithelial and connective tissue
layers
Attaches epithelium to connective tissue below
Made up of:
 Basal lamina: thin, non-cellular, supportive sheet made of
proteins



Superficial layer
Acts as a selective filter
Assists epithelial cell regeneration by moving new cells
 Reticular fiber layer


Deeper layer
Support
Glands
Epithelial cells that make and secrete a
product
Products are water-based and usually contain
proteins
Classified as:


Unicellular vs. multicellular
Exocrine vs. Endocrine
Page 138
Glands:
epithelial cells that make and
secrete a water-based substance w/proteins
Exocrine Glands





Secrete substance onto body surface or into
body cavity
Activity is local
Have ducts
Unicellular or Multicellular
(ex) goblet cells, salivary, mammary,
pancreas, liver
Glands:
epithelial cells that make and
secrete a water-based substance w/proteins
Endocrine Glands





Secrete product into blood stream
Either stored in secretory cells or in follicle
surrounded by secretory cells
Hormones travel to target organ to increase
response (excitatory)
No ducts
(ex) pancreas, adrenal, pituitary, thyroid
4 Types of Tissue
1)Epithelium
2)Connective
3)Muscle
4)Nervous
4 Types of Connective Tissue
1)
2)
3)
4)
Connective Tissue Proper
Cartilage
Bone Tissue
Blood
Connective Tissue (CT):
most abundant and diverse tissue
Four Classes
Functions include connecting, storing &
carrying nutrients, protection, fight
infection
CT contains large amounts of non-living
extracellular matrix
Contains a variety of cells and fibers
Some types vascularized
All CT originates from mesenchyme

Embryonic connective tissue
Fibers in Connective Tissue
Fibers For Support

Reticular:
 form networks for structure & support
 (ex) cover capillaries

Collagen:
 strongest, most numerous, provide tensile strength
 (ex) dominant fiber in ligaments

Elastic:
 long + thin, stretch and retain shape
 (ex) dominant fiber in elastic cartilage
Components of Connective Tissue
Fibroblasts:



cells that produce all fibers in CT
produce + secrete protein subunits to make them
produce ground matrix
Interstitial (Tissue) Fluid



derived from blood in CT proper
medium for nutrients, waste + oxygen to travel to cells
found in ground matrix
Ground Matrix (substance):



part of extra-cellular material that holds and absorbs
interstitial fluid
Made and secreted by fibroblasts
jelly-like with sugar & protein molecules
1) Connective Tissue Proper
Two kinds: Loose CT & Dense CT

Functions
 Support and bind to other tissue
 Hold body fluids
 Defends against infection
 Stores nutrients as fat

Each function performed by different kind
of fibers and cells in specific tissue
Defense from Infection
Areolar tissue below epithelium is body’s first
defense
Cells travel to CT in blood




Macrophages-eat foreign particles
Plasma cells-secrete antibodies, mark molecules for
destruction
Mast cells-contain chemical mediators for
inflammation response
White Blood Cells = neutrophils, lymphocytes,
eosinophils-fight infection
Ground substance + cell fibers-slow invading
microorganisms
Loose CT Proper
Areolar CT



All types of fibers present
All typical cell types present
Surrounds blood vessels and nerves
Specialized Loose CT Proper
Adipose tissue



Loaded with adipocytes, highly vascularized, high
metabolic activity
Insulates, produces energy, supports
Found in hypodermis under skin
Reticular CT



Contains only reticular fibers
Forms caverns to hold free cells, forms internal
“skeleton” of some organs
Found in bone marrow, holds blood cells, lymph
nodes, spleen
Dense/Fibrous Connective Tissue
Contains more collagen
Can resist extremely strong pulling forces
Regular vs. Irregular

Regular-fibers run same direction, parallel to pull
 (eg) fascia, tendons, ligaments

Irregular-fibers thicker, run in different directions
 (eg) dermis, fibrous capsules at ends of bones
Dense regular
Dense irregular
Components of CT Proper Summarized
Cells
Matrix
Fibroblasts
Gel-like ground
substance
Defense cells
Collagen fibers
Reticular fibers
Elastic fibers
-macrophages
-white blood cells
Adipocytes
2) Cartilage
Chondroblasts produce cartilage
Chondrocytes mature cartilage cells

Reside in lacunae
More abundant in embryo than adult
Firm, Flexible
Resists compression

(eg) trachea, meniscus
Avascular (chondrocytes can function w/ low oxygen)
NOT Innervated
Perichondrium



dense, irregular connective tissue around cartilage
growth/repair of cartilage
resists expansion during compression of cartilage
Cartilage in the Body
Three types:

Hyaline





most abundant
fibers in matrix
support via flexibility/resilience
(eg) at limb joints, ribs, nose
Elastic
 many elastic fibers in matrix too
 great flexibility
 (eg) external ear, epiglottis

Fibrocartilage
 resists both compression and
tension
 (eg) meniscus, annulus fibrosus
Components of Cartilage Summarized
Cells
Matrix
Chondrocytes
Gel-like ground
substance
Chondroblasts
Lots of water
(in growing cartilage)
Fibroblasts
Some have collagen and
elastic fibers
3) Bone Tissue:
(a bone is an organ)
Well-vascularized
Function:





support (eg) pelvic bowl, legs
protect (eg) skull, vertebrae
mineral storage (eg) calcium, phosphate
(inorganic component)
movement (eg) walk, grasp objects
blood-cell formation (eg) red bone marrow
Bone Tissue
Osteoblasts

Secrete organic part of bone matrix
Osteocytes



Mature bone cells
Sit in lacunae
Maintain bone matrix
Osteoclasts

Degrade and reabsorb bone
Periosteum

External layer of CT that surrounds bone
 Outer: Dense irregular CT
 Inner: Osteoblasts, osteoclasts
Endosteum


Internal layer of CT that lines cavities and covers trabeculae
Contains osteoblasts and osteoclasts
academic.kellogg.cc.mi.us/.../skeletal.htm
Compact Bone
External layer
Osteon (Haversian system)



Parallel to the long axis of the bone
Groups of concentric tubules (lamella)
Lamella = layer of bone matrix where all fibers run in the same
direction
 Adjacent lamella fibers run in opposite directions

Haversian Canal runs through center of osteon
 Contains blood vessels and nerves
 Connected to each other by perforating (Volkman) canals
Interstitial lamellae fills spaces and forms periphery
www.mc.vanderbilt.edu/.../CartilageandBone03.htm
Bone Anatomy: Spongy bone
Spongy bone (cancellous bone): internal layer

Trabeculae: small, needle-like pieces of bone form
honeycomb




each made of several layers of lamellae + osteocytes
no canal for vessels
space filled with bone marrow
not as dense, no direct stress at bone’s center
Shapes of Bones
Flat = skull, sternum, clavicle
Irregular = pelvis, vertebrae
Short = carpals, patella
Long = femur, phalanges,
metacarpals, humerus
Anatomy of a Long Bone
Diaphysis


Medullary Cavity
Nutrient Artery & Vein
2 Epiphyses


Epiphyseal Plates
Epiphyseal Artery & Vein
Periosteum

Does not cover epiphyses
Endosteum


Covers trabeculae of spongy bone
Lines medullary cavity of long bones
training.seer.cancer.gov/.../illu_long_bone.jpg
2 Types of Bone Formation
Intramembranous Ossification


Membrane bones: most skull bones and clavicle
Osteoblasts in membrane secrete osteoid that mineralizes
Endochondral Ossification: All other bones




Begins with a cartilaginous model
Cartilage calcifies
Medullary cavity is formed by action of osteoclasts
Epiphyses grow and eventually calcify
 Epiphyseal plates remain cartilage for up to 20 years
Bone Growth & Remodeling
GROWTH

Appositional Growth = widening of bone
 Bone tissue added on surface by osteoblasts of periosteum
 Medullary cavity maintained by osteoclasts

Lengthening of Bone
 Epiphyseal plates enlarge by chondroblasts
 Matrix calcifies (chondrocytes die and disintegrate)
 Bone tissue replaces cartilage on diaphysis side
REMODELING

Due to mechanical stresses on bones, their tissue needs
to be replaced
 Osteoclasts-take up bone ( = breakdown) release Ca2++ , PO4 to
body fluids from bone
 Osteoblasts-form new bone by secreting osteoid

Ideally osteoclasts & osteoblasts work at the same rate!
Components of Bone Tissue Summarized
Cells
Matrix
Osteblasts
Gel-like ground substance
calcified with inorganic
salts
Fibroblasts
Collagen fibers
Osteocytes
Osteoclasts
4) Blood: Atypical Connective Tissue
Function:



Transports waste, gases, nutrients,
hormones through cardiovascular system
Helps regulate body temperature
Protects body by fighting infection
Derived from mesenchyme
Hematopoiesis: production of blood cells


Occurs in red bone marrow
In adults, axial skeleton, girdles, proximal
epiphyses of humerus and femur
Blood Cells
Erythrocytes: (RBC) small, oxygen-transporting
most abundant in blood
no organelles, filled w/hemoglobin
pick up O2 at lungs, transport to rest of body
Leukocytes: (WBC) complete cells , 5 types
fight against infectious microorganisms
stored in bone marrow for emergencies
*Platelets = Thrombocytes:
fragments of cytoplasm
plug small tears in vessel walls, initiates clotting
Components of Blood Summarized
Cells
Matrix
Erythrocytes
(red blood cells)
Plasma
(liquid matrix)
Leukocytes
(white blood cells)
NO fibers
*Platelets
(cell fragments)
4 Types of Tissue
1)Epithelium
2)Connective
3)Muscle
4)Nervous
Muscle Tissue
Muscle cells/fibers


Elongated
Contain many myofilaments: Actin & Myosin
FUNCTION




Movement
Maintenance of posture
Joint Stabilization
Heat Generation
Three types: Skeletal, Cardiac, Smooth
Skeletal Muscle Tissue
(each skeletal muscle is an organ)
Cells



Long and cylindrical, in bundles
Multinucleate
Obvious Striations
Skeletal Muscles-Voluntary
Connective Tissue Components:



Endomysium-surrounds fibers
Perimysium-surrounds bundles
Epimysium-surrounds the muscle
Attached to bones, fascia, skin
Origin & Insertion
academic.kellogg.cc.mi.us/.../muscular.htm
Cardiac Muscle
Cells




Branching, chains of cells
Single or Binucleated
Striations
Connected by Intercalated discs
Cardiac Muscle-Involuntary
Myocardium-heart muscle

Pumps blood through vessels
Connective Tissue Component

Endomysium: surrounding cells
www.answers.com
Smooth Muscle Tissue
Cells
Single cells, uninucleate
No striations
Smooth Muscle-Involuntary
2 layers-opposite orientation (peristalsis)
Found in hollow organs, blood vessels
Connective Tissue Component
Endomysium: surrounds cells
4 Types of Tissue
1)Epithelium
2)Connective
3)Muscle
4)Nervous
Nervous Tissue
Neurons: specialized nerve cells conduct impulses

Cell body, dendrite, axon
Characterized by:



No mitosis (cell replication)
Longevity
High metabolic rate
www.morphonix.com
Nervous Tissue: control
Support cells (= Neuroglial): nourishment,
insulation, protection





Satellite cells-surround cell bodies within ganglia
Schwann cells-surround axons (PNS)
Microglia-phagocytes
Oligodendrocytes-produce myelin sheaths around axons
Ependymal cells-line brain/spinal cord, ciliated, help
circulate CSF
Brain, spinal cord, nerves
Integumentary System
Functions

Protection
 Mechanical, thermal, chemical, UV




Cushions & insulates deeper organs
Prevention of water loss
Thermoregulation
Excretion
 Salts, urea, water

Sensory reception
Microanatomy - Layers of the
Skin
Epidermis
 Epithelium
Dermis

Connective tissue
Hypodermis / subcutis


Loose connective tissue
Anchors skin to bone or muscle
Skin Appendages = outgrowths of epidermis



Hair follicles
Sweat and Sebaceous glands
Nails
www.uptodate.com/.../Melanoma_anatomy.jpg
Cell Layers of the Epidermis
Stratum corneum

Dead keratinocytes
Stratum lucidum


Only in “thick” skin
Dead keratinocytes
Stratum granulosum

Water proofing
Stratum spinosum

Resists tears and tension
Stratum basale



Sensory receptors
Melanocytes
Keratinocytes (in all layers)
15minbeauty.blogspot.com
Layers of the Dermis
Highly innervated
Highly vascularized
Collagen & Elastic fibers
2 layers:

Papillary layer (20%)





Areolar CT
Collagen & Elastic fibers
Innervation
Hair follicles
Reticular layer (80%)
 Dense irregular CT
 Glands


sebum
2.5 million sweat glands!!
 Smooth muscle fibers
 Innervation
www.uptodate.com/.../Melanoma_anatomy.jpg
Hypodermis
Also called superficial fascia
Areolar & Adipose Connective Tissue
Functions



Store fat
Anchor skin to muscle, etc.
Insulation
Structure of Tubular Organs
LUMEN
Tunica Mucosa



Lamina epithelialis
Lamina propria
Lamina muscularis mucosa
Tunica Submucosa
Tunica Muscularis


Inner circular
Outer longitudinal
Tunica Adventitia / Serosa


Adventitia – covers organ directly
Serosa – suspends organ in the peritoneal cavity