2. Animals are clasiffied ionto two big groups :
- Vertebrates ( animals with backbones )
- Invertebrates ( animals without backbones )
- mammals
- fish
- birds
- amphibians
- reptiles
CLASS | COMMON CHARACTERISTICS |
a) Mammals | · Warm-blooded · Body is covered with hair or fur · Breathe through lungs · Give birth to young alive ( except platypus and ant-eater ) · Females have mammary glands and feed to young ones with milk · Have a pair of external ears |
b) Fish | · Cold-blooded · Body is covered with scales · Breathe by using gills · Most of them lay eggs are fertilised externally · Have fins and swim bladders to help them to swim |
c) Birds | · Warm-blooded · Body is covered with feathers · Breathe through lungs · Lay eggs with shells · Have beaks and scaly legs · Have wings and most of them can fly |
d) Amphibians | · Cold-blooded · Body is covered with moist skin · Adults breathe by using lungs or the skin. The young ones breathe through gills. · Lay eggs without shells in water and the eggs are fertilised externally · Can live on land or in water |
e) Reptiles | · Cold-blooded · Body is covered with dry, tough and scaly skin · Breathe through lungs · Lay eggs with thick shells · Most of them live on land |
5. Invertebrates
- Invertebrates are animals without backbones.
- Most of the invertebrates are small in size.
- Their bodies are supported by body fluid and hard exoskeletons. Examples of invertebrates are cockroaches, earthworms and spider.
EXAMPLES OF VERTEBRATES :
- MAMMALS
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| WHALE |
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| DOLPHIN |
- FISH
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| FISH |
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| FISH |
- BIRDS
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| SPARROW |
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| BIRD |
- AMPHIBIANS
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| FROG |
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| TOAD |
- REPTILES
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| CROCODILE |
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| TORTOISE |
EXAMPLES OF INVERTEBRATES :
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| COCKROACHES |
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| SPIDER |