Lesson 1 :

Diversity of living organisms

& their classification

Lesson 2:

Adaptation of Living Organism in

diverse environment

Lesson 3:

Adaptation & Continuity of life

1. Living organisms are different. In order to study them easily & make benefit of them we put them in groups (classes).

2. Living organisms -you study this year – can be classified into 3 main classes: microorganisms – plants – animals.

T hey exist in every environment. They ‘re not seen by the naked eye & are only seen by a microscope.

Activity 1:

• Aim to : Look at the water from a potted plant through a microscope.

• Materials :

S ome irrigation water from a potted plant - a dropper – glass slide – a plastic cover – some dye – a light microscope.

• Procedure (steps of work)

1. Put a drop of water taken from a potted plant on a glass slide.

2. Add a drop of dye to the water on the slide.

3. Put the plastic cover on the water & examine the slide under the microscope.

• Observation :

1. Many microorganisms are seen moving in the slide.

2. M icroorganisms have different shapes.

1. Plants like corn, wheat, palm & camphor have roots, stems & leaves.

2. Other plant – like organisms called algae . don’t have roots, stems or leaves. Brown & red algae don’t have roots, stems or leaves. They form long threads which live in marine (related to sea) environment .

• Classifying plants according to the reproductive style:

Plants which reproduce by spores	Plants which reproduce by seeds
	Gymnosperms	angiosperms
		Monocotyledons	Dicotyledons
Voughair Adiantum	Pine Cycas	Maize Wheat	Bean Pea

Bean

corn

Cycas

Pine

• Classifying animals according to body support

Internal skeleton & back bone (Vertebrates)	Absence of internal support (Invertebrates)
Fish A mphibians Bird Reptiles Mammals	Supported body (external skeleton)	Soft body (without external support)
	S nail M ussel	J ellyfish Earthworm Octopus

• Classifying arthropods according to the number of legs:

Insects	Arachnids	Myriapods
F ly Honey-bee Ant	S pider S corpion	S colopendra J ulius

• Identifying the teeth type & number in some mammals:

Animals with teeth				Animals without teeth (Edentates)
Animals with extended teeth	Animals with sharp canines	Animals with sharp incisors
		Rodents	Lagomorphs
H edgehog	Lion Tiger Tiger	Rat Squirrel S quirrel	R abbit	Sloth A rmadillo

1. Taxonomy is the science of classifying living organisms in groups according to similarities.

2. All organisms with similar shape & are able to reproduce & give birth of fertile animals form a group called species.

3. An example: Horses (brown, white or black) are one species because they can mate (reproduce) & give birth of ponies that grow into horses & reproduce again & thus the species doesn’t become extinct. Donkies form a species for the same reasons. When a female horse mates with a male donkey , it gives birth to a mule. The mule isn’t fertile & can’t reproduce.

4. The species is the base of taxonomy.

1. Fill in the blanks:

Class	An organism that belongs to this class
Angiosperms
Arthropods
Rodents
	Octopus
	Sloth
	Wheat
Vertebrate
	Vougheir
Dicotyledons
Insects
Unicellular organism

2. Choose the correct answer:

1. Microorganisms are seen by……………………

(naked eyes – mirror – microscope)

2. ……………………………don’t have roots, stem or leaves.

(adiantum – brown algae – maize)

3. Cycas belongs to…………………………

(angiosperms – aglae – plants)

4. The bodies of reptiles are …………………………………

(externally supported – soft – internally supported)

5. Spiders & ……………………………….are arachnids.

(scorpions – bees – files)

6. The basic unit of classification is the……………………….

(individual – species – microorganisms)

3. Write the scientific term:

   Unicellular organisms present in all environments.
   The group of terrestrial (on land) plants which reproduce by spores.
   The class of animals with 3 pairs of jointed legs.
   A group of animals with similar shape, they reproduce together & give birth to fertile individuals.

4. Give reasons for the following:

1. Tigers have sharp canines.

…………………………………………………………………………………………………………………………………………………………………………………………………………

2. Scientists classify living organisms.

………………………………………………………………………………………………………………………………………………………………………………………………………

3. Jellyfish has soft body.

………………………………………………………………………………………………………………………………………………………………………………………………………..

4. Spiders & ants are classified in 2 different classes.

………………………………………………………………………………………………………………………………………………………………………………………………………..

5. The front teeth of hedgehog extend outwards.

………………………………………………………………………………………………………………………………………………………………………………………………………..

6. When a zebra mates with a donkey , their offspring is infertile.

…………………………………………………………………………………………………………………………………………………………………………………………………………

5. Mention a difference between the pair of organisms:

1. Rabbit & squirrel

…………………………………………………………………………………………………..

2. Bean & wheat

…………………………………………………………………………………………………..

3. Pine & palm

…………………………………………………………………………………………………..

4. Jellyfish & fish

…………………………………………………………………………………………………..

5. Euglena & amoeba

…………………………………………………………………………………………………..

6. Hedgehog & sloth

…………………………………………………………………………………………………..

7. Earth worm & scorpion

…………………………………………………………………………………………………..

8. Paramecium & Julius

…………………………………………………………………………………………………..

1. L iving organisms live in different environments. The conditions of these environments are diverse. The desert is hot & its soil is sandy. Camels’ feet are thick flat pads to walk on the sand. The mountain has rocky surface. Horses’ hooves are hard to walk on the rocks.

2. The modification in the living organisms that enable them to adapt to the environment is called adaptation.

A daptation has 3 types:

Modification of structure	Modification of function	Modification of behavior
Examples: The structure of camel’s pad & horse’s hooves is suitable to their environment.	Examples: Sweat is secreted to adapt with hot weather. Snakes secrete poison to capture their preys (rat).	Examples: Birds migrate to warm places in winter. Bats are active during night while other organisms (horses) are active during day.

Structural adaptation :