Chapter #1
Classification of Living
Organisms
Classification
What is life……………?
A set of characteristic/traits, that are
present in all the living things but not in
nonliving.
 All living things have to perform seven life
processes.
Do you know what they are……..?
MRS-GREN
If something does not perform all
of the seven life processes then it
is not alive.
Movement
Respiration
Sensitivity
Growth
Reproduction
Excretion
Nutrition
1. Movement
Is an action by an organism or part of
organism causing a change of position
or place
2. Respiration
Respiration
Respiration is the process in which the cells of an organism
obtain energy by combining oxygen and glucose, resulting
in the release of carbon dioxide, water, and ATP
(energy).
Glucose + Oxygen  ENERGY + Carbon dioxide + Water
3. Sensitivity
Sensitivity is the ability of living things to detect changes
in their surroundings and respond to these changes.
Humans have five senses; do you know what they
are?
Touch
Skin
Taste
Tongue
Smell
Nose
Sight
Eyes
Hearing
Ears
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Which organs are
associated with these
senses?
Sensitivity in Plants
pitcher plant
Shameplant plant
4. Growth
Is permanent increase in
size and dry mass.
5. Reproduction
All organisms need to reproduce. Reproduction is process
in which organisms produce young ones of their own kind.
If organisms did not reproduce, then once those organisms
died there would be no more of the species left.
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5. Reproduction
 Some animals reproduce by laying
eggs.
Example: Birds
 Some animals reproduce by giving birth to live young.
Example: Mammals
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Plant Reproduction
Some plants reproduce using the wind to carry pollen from
one flower to another.
Some plants reproduce
using insects or birds
to carry pollen from
one flower to another.
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6. Excretion
Excretion is the process where an organism gets rid of
metabolic waste products that would otherwise cause it
harm.
7. Nutrition
Nutrition is the taking in of materials for growth
development and energy.
Nutrition
 Carnivores
 Omnivores
 Herbivores
Green plants make their own food using
sunlight, water and carbon dioxide. This
process is called PHOTOSYNTHESIS.
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Additional Characteristics
 When we study the living organism
under the microscope
 They all are made up of cells
Cell contain
• Cytoplasm
• Cell membrane
• DNA
• Ribosome
• Enzymes
Human skin Cells
Objectives:

Classification
 Five Kingdoms of Life.
 Distinct characteristics of each of the Five
Kingdoms of Life.
 Characteristics of each Kingdom.
1.2. Classification
Why do we need to classify living things?
 There are about 1.4 million
species of discovered
organisms on the earth
 We divide them into different
groups to make studying them
easier
Means of Classification
I. Physical appearance
•
All the organism with similar
phenotype/characteristics are put in one group
e.g. Morphology
Anatomy
II. Using DNA Sequences to help classification
 Based on the arrangement of DNA Bases (ATCG)
 Modern method of classification of species
The classification system
Swedish naturalist 1735
 He divided all the different kind of
living things into groups called
species
12000 species
Linnaeus classification was based on
same appearance and same behavior
Linnaeus
Classification reflects evolutionary
relations
• More the organisms share features, evolved
from more recent common ancestor and vice
versa
Base sequence in DNA are used as a
means of classification
• More similar the base sequences, more
closely related species are, sharing more
recent common ancestor and vice versa
Classification of Living Organism
KING PHILIP CAME OVER FOR
GOOD SPAGHETTI
Binomial system of classification
• Binomial = two names (genus and
species)
• Worldwide system used by scientists
• The genus always has a capital letter e.g.
Panthera leo is the binomial name for lion
Species
The group of organisms which can
freely interbreed with each other
to produce fertile offspring
Five Kingdom System
 Organisms are divided into five large groups called
kingdoms
Kingdom Animalia
 Characteristics
 Multicellular
 Cells have nucleus but no cell
wall and chloroplast
 Feed on organic substances
made by other living organism
Kingdom Plantae
Characteristics
 Multicellular
 Cells have nucleus and also contain
cell wall
 Cell wall is made up of cellulose and
often contain cytoplasm
 Prepare their own food by
photosynthesis
Fungi kingdom
Eg: Mushrooms
Characteristics
 Multicellular
 Have nuclei
 Have cell wall, made of chitin
 Do not have chlorophyll
 Feed by saprophytic or parasitic
nutrition
Edible
Mushrooms
Nonedible
Mushrooms
kingdom Protista
Contains quite a mixture of organisms
Characteristics:
 Multicellular or Unicellular
 Cells have a nucleus
Cells may or may not have a chloroplasts
Some feed by photosynthesis and other feed
on organic substances made by other organisms
Animals like
Plants like
Kingdom Monera
Characteristics
 Prokaryotes
 Unicellular
 No true nucleus
 Have cell wall that is made of
peptidoglycan
 No membrane bounded
organelles
Viruses
Viruses
Viruses are not true living
things
They can do nothing until
they enter a living cell.
Diseases
 Common cold
 Influenza
 AIDs( HIV)
Scientists do not classify a virus as a living thing. This is
because:
 It does not show all seven processes for life
 when it enters a cell, it changes the way a
cell works so it can make copies of the virus.
Characteristics of Viruses
 Very small (100 times
smaller than bacteria)
 No typical cell structure
 Contain strand of DNA or
RNA
 Surrounded by a protein
coat called Capsid
 The only life process they
can show is the
reproduction inside the
host cell
1.5. Classifying Animals
Phylum Vertebrates
Animals with a supporting rod
running along the length of the body
They have the backbone
(vertebral column)
Vertebrae=the bones that make up the spine
Class Fish
All live in water
except for one or two
(mudskipper) which spend short period of time
breathing air
Characteristics
Vertebrate with
scaly skin
Have gills
Have fins
Class Amphibians
Most of the amphibians live on land but they always go back
to the water to breed
Toad, Frogs and Salamanders
Characteristics
 Vertebrates with moist scale-less skin
 Egg laid in the water, Larva ( tadpole) lives
in the water
 Adults often lives on the land
 Larva has gills and Adult has lungs
Class Reptiles
Snakes, crocodiles, Lizards, turtles and
tortoises
Characteristics
They are vertebrate with Scaly Skin
Lay eggs with rubbery shells
They Don’t need go back to the water for
breeding because their eggs have water
proof shells which stops them from drying out
Class Birds
 Birds lay eggs with hard shells
(like reptiles)
Characteristics
 Vertebrate with feathers
 Forelimbs have become wings
 Lay eggs with hard shells
 Endothermic
 Have Beak
 Heart has four chambers
Class Mammals
Characteristics
Vertebrate with hairs on the body
Have placenta
Young Feed on milk from mammary gland
Endothermic
Have Diaphragm
Heart has four chambers
Have different type of
teeth(Incisors, canines, premolars and molars)
Phylum Arthropods
 Also known as invertebrates
 They are more successful group, because they have
waterproof exoskeleton that allow them to live in the
dry conditions
They have many kinds on the earth than other
species
Characteristics
Several pairs of legs
Exoskeleton
Insects
They are mainly terrestrial
Arthropods with three pairs of legs
Two pairs of wings
Body is divided into head thorax and abdomen
Breath through trachea
Most insects reproduce oviparously, i.e. by laying eggs.
The eggs are produced by the female in a pair of ovaries.
At the time of fertilization, the eggs travel along
oviducts to be fertilized by the sperm and are then
expelled from the body ("laid"),
Crustaceans
Crabs, Lobsters and woodlice
Characteristics
They breath through gills
Most of them live in the wet
places
Arthropods with more than four
pairs of legs
Breath through Gills
 Fusion of a sperm with an egg,
 Some crustaceans are parthenogenetic;
 That is, they produce eggs that develop
without being fertilized by a sperm.
Arachnids
Spiders, Ticks and Scorpions
They are land-dwelling
Characteristics
Arthropod with four pairs of
jointed legs
 Breath through gills
Internal fertilization.
Myriapods
These are the centipedes and millipedes
Characteristics
Body consist of many segments
Each segment has jointed legs
Fertilization is internal
Centipedes generally have a life span of 4 to 6
years
millipedes live for 1 to 10 years
Classification of Plants
 Plants are organisms that have cell with the
cell wall made up of Cellulose
 Some parts of the plants are green
green pigment (chlorophyll)
Which absorb energy from sunlight
The plant uses this energy to make glucose using
carbon dioxide and water from the environment.
this process is known as photosynthesis
 Ferns /Moses
 Flowering plants
Ferns
Fern have leaves called fronds
They don’t produce flower
They reproduce by mean of spores produced on
the underside of the fronds
Characteristics
Plants with roots, stems and leaves
Have leaves called fronds
Don’t produce flowers
Reproduce by spores
Flowering Plants
They can be tiny or very large
Many trees are flowering plant
Characteristics
 Plants with root stem and leaves
 Reproduce sexually by means of
flowers and seeds
 Seeds are produced inside the ovary
in the flower
Flowering plants can be divided
into two main groups
1. Monocotyledonous
2. Dicotyledonous
Monocotyledonous
Characteristics
They have only one cotyledon in their seeds
They usually have the branching root system
They have leaves in which the veins run parallel to one
another
Dicots or Dicotyledon
They have two cotyledons in their seeds
They frequently have tap root system
Their leaves are often broader than monocots
leaves, and they have network of branching
veins.
Dichotomous Keys
A dichotomous key is a
method for determining
the identity of something.
 It is like a road map
made of questions with a
yes/no answer.
 Depending on the answer
we will follow one path
or another
Keys are used to identify organisms based on
a series of questions about their features
 Dichotomous means ‘branching into two’
and it leads the user through to the name
of the organism by giving two descriptions
at a time and asking them to choose
Yes
No
 Each choice leads the user onto another
two descriptions
 In order to successfully navigate a key,
you need to pick a single organism to
start with and follow the statements
from the beginning until you find the
name
 You then pick another organism and start
at the beginning of the key again,
repeating until all organisms are named