Animals are classified into two groups:
1) Those that have a backbone. These are called Vertebrates
2) Those that do not have a backbone. These are called Invertebrates
These are animals with no backbones.
The common invertebrates are insects such as mosquitoes and houseflies.
Other animals like ticks and spiders, mites, worms, snails, slugs, millipedes, centipedes and crabs.
Insects are animals that have three body parts and six legs.
Vertebrates are animals with backbones.
Vertebrates can be classified into either cold blooded or warm blooded.
The cold-blooded vertebrates can vary or change their body temperature according to the temperature of the surrounding environment.
The best term to refer to these vertebrates is ectotherms because their body temperature varies with that of their environment.
Examples of cold-blooded animals are: - fish - amphibians - reptiles
What characteristics do fish have?
Fish have the following characteristics:
1. Fish breathe through gills
2. Fish reproduce by laying eggs
3. Fish have fins used for movement, steering and balancing
4. Ectotherms Body temperature varies with that of the environment
5. Fish entire body is covered by structures called scales
6. External fertilization The sperms and eggs are shed in the water where they fuse.
Examples of fish are Nile perch and tilapia
Amphibians have the following characteristics:
1. They do not have scales around their body but have a soft, moist skin which they also use for breathing.
2. They breathe using gills when they are still young (tadpoles) and lungs when they mature
3. They lay eggs in water. The male covers the eggs with sperms therefore, fertilizing them externally.
Reptiles have the following characteristics:
1. Their bodies are covered with scales
2. They live on land and breathe using lungs. Some live in water e.g. turtles
3. They lay eggs
4. They have four limbs, except the snakes
Land reptiles (those that live on land) are lizards, tortoises and snakes.
Water reptiles (those that live in water) are turtles, some snakes and crocodiles.
such as birds and mammals, have a constant body temperature, that is, their temperatures do not change with that of the environment.
Birds have the following characteristics:
1. Their bodies are covered with feathers but they have scales on their legs
2. They breathe using the lungs
3. The eggs are fertilised within the body of the female. Fertilisation is internal.
4. Their eggs are covered in a shell, and the young in the eggs feed on stored yolk and albumen (the egg white).
5. Parents take care of the young.
Different birds can be grouped into either of the following :
Chickens have short, strong and pointed beaks for picking up GRAINS or SEEDS from the ground.
Chickens are an example of GRAIN EATERS
However, they are also classified among the SCRATCHING BIRDS because they find some of their food by scratching the surface of the earth.
They also feed on worms and insects.
Another example of grain eaters is the guinea fowl.
Play the next video to learn more on grain eaters:
The sunbird has a long, thin and slanted beak to ensure it can reach through the petals of a flower to suck the nectar on which it feeds.
It is also classified among PERCHING BIRDS because it has to perch on plants as it sucks nectar.
It is small and very light, to ensure it doesn’t break the upper parts of the plant on which it perches.
Another example of nectar feeders is the humming bird.
Hawks have strong, short and hooked beak that is used for tearing flesh or meat from the bones of their prey.
They feed on animals such as rats and chicks.
They have long curved claws to grip their prey with.
They hunt for their food and are referred to as BIRDS OF PREY
Another adaptation they have is SHARP EYESIGHT for spotting prey from a distance.
Play the next video:
Most of the animals that we see around us are mammals.
Examples of mammals are man, dogs and cats.
1. Most mammals live on land, though some for example whales, seals and dolphins live in water.
These mammals that live in water are called marine mammals.
2. Their bodies are covered with fur or hair
3. They breathe by the use of lungs
4. Most have four limbs: some walk on two legs, for example man, some walk on four limbs, for example cats and cows, some fly using wings, for example bats, some hop or leap like the kangaroo, while others swim for example dolphins and whales.
The mammals that have hoofs and are called hoofed mammals.
They include cows and goats.
5. They reproduce by giving birth to young ones though some primitive ones called monotrems lay eggs which hatch to produce young ones.
An example of mammals that lay eggs is the duck-billed platypus.
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6. Fertilisation is internal
7. They feed their young ones by suckling milk from the mammary glands
Mammals can be classified according to their feeding habits.
Some mammals feed on plants only (herbivores) , others feed on animal products (flesh) only (carnivores) while others feed on both animal products and plants (omnivores).
Herbivores can be classified into two classes namely: -
Grazers: these are herbivores that feed on grass only.
They include cows, donkeys, dik diks and impalas.
Browsers: these are herbivores that feed on tree leaves and twigs.
They include giraffes, antelopes and goats.
1. They possess premolar and molar teeth whose function is to crush and grind the tough vegetation.
2. They have no upper incisors but instead have a horny pad which they use together with the lower incisors to hold and cut vegetation.
3. Their jaws move from side to side when they chew.
4. They have a gap called DIASTEMA, which separates the cutting teeth (incisors and canines) from the grinding teeth (premolars and molars).
The gap allows for free movement of the tongue.
These are mammals that feed on flesh only. Carnivores include dogs, cats, lions and leopards.
Characteristics of carnivores
1. They have sharp pointed incisor teeth, which they use to bite and cut flesh.
2. They have long pointed canines, which they use to pierce, hold and tear the flesh of their prey.
3. They possess premolars and molars which have pointed and sharp surfaces, which allow them to slice pieces of food.
4. Their jaws are strong and move up and down, during chewing.
These are mammals that feed on both plant and animal products.
Omnivores include man and monkeys.
Characteristics of omnivores
1. They have incisors which they use to bite off or cut pieces of food.
2. They have pointed canines which are used to bite off and tear away pieces of food.
3. They have large and flat premolars used to chew and grind food.
4. They have molars that are slightly bigger than premolars which they also use to grind and chew food.
The animals that are kept at home are called DOMESTIC ANIMALS
Domestic animals include pets and livestock. Pets include cats, dogs and pigeons.
Livestock or farm animals are kept for the purpose of benefiting us from the products they make.
Livestock can be classified according to the product they offer.
Livestock can be classified as:
These are domestic animals that are kept for eggs and meat.
Examples of poultry are chicken, ducks, turkeys and geese.
Chickens can be classified as either layers or broileres.
Layers are the chicken kept for eggs. Broilers are kept for meat.
Poultry products include:
layers - chicken kept for egg laying;
broilers - chicken kept for meat
ducks - kept for eggs and meat
turkey - kept for eggs and meat
geese - kept for eggs and meat.
These are livestock that are either kept for meat or for milk.
Cattle include cows and bulls.
Cattle can be grouped into;
a) Beef cattle- which are kept for meat for example, Boran, Hereford, Sahiwal, and Redpoll
b) Dairy cattle- which are kept for milk. Examples of dairy cattle include the Fresian, Guernsey, Ayrshire and Jersey.
These are domestic animals that are kept for their meat and the fur which makes wool.
The meat of sheep is called mutton.
The wool is shaved and made into clothes.
Examples of sheep are Merino (kept for mutton and wool) and Dorper (kept for mutton).
They are livestock that are kept for their meat, which is also called mutton and for milk.
Examples of goats are Toggenburg (kept for milk and mutton) and the East African goat (kept for mutton).
The duck has a flat and broad beak with the lower part fitting into the upper one.
The beak is used to SIEVE or FILTER small plants and animals from the water from which they hunt for their food.
They feed on fish and other small animals.
Ducks are also classified among SWIMMING BIRDS because they are good swimmers.
They have webbed feet which they use to swim while looking for food.
Another example of filter feeders is the flamingo.
Standard 5
1. The information below is about some vertebrates U, V, W, and X.
Vertebrate |
Characteristic |
U |
Damp skin, lays eggs, cold-blooded |
V |
Feathers, lays eggs, warm-blooded |
W |
Hair, live young, warm-blooded |
X |
Scales, lays eggs, cold-blooded |
Which one of the following vertebrates could be a reptile?
A. U B. V C. W D. X
2. Which one of the following statements about frogs and crocodiles is WRONG?
A. Both lay eggs
B. Their body temperature changes with that of the surroundings
C. Both have scales
D. Both spend some time in water
3. A termite differs from a spider in that
A. A termite has three body parts while a spider has two
B. A termite has simple eyes while a spider has compound eyes
C. A termite has eight legs while a spider has six
D. A termite is segmented while a spider is not segmented.
4. From the following lists of animals, choose the one that consists of mammals only.
A. Bat, squirrel, tortoise, porcupine
B. Whale, rabbit, bat, kangaroo
C. Whale, hedgehog, owl, salamander
D. Elephant, python, lion, antelope
5. Sankuri classified some of the animals he had seen during a visit to a National park into two groups using a certain characteristic:
Group I |
Group II |
Lizard |
Mouse |
Frog |
Ostrich |
Crocodile |
Leopard |
Which one of the following shows the characteristics that Sankuri used?
Group I |
Group II |
A. Carnivore |
Herbivore |
B. Lays eggs |
Bear their young life |
C. Body temperature varies |
Body temperature constant |
D. Do not care for their young |
Care for their young |
6. The chart below shows a simple classification of vertebrates.
Which one of the following groups of vertebrates does W represent?
A. Reptiles B. Amphibians C. Fish D. Birds
7. A pupil classified some animals as shown in the chart below:
Which of the following animals was NOT classified correctly?
A. Housefly B. Spider C. Chameleon D. Lizard
8. Some pupils used the chart shown below to group small animals they had collected.
Which one of the following is represented by Q?
A. Weevil B. Flea C. Tick D. Bedbug
9. Which one of the following animals lay eggs, breathes by means of lungs and has a constant body temperature?
A. Frog B. Crocodile C. Duck D. Whale
10. Which one of the following animals is CORRECTLY MATCHED with the number of legs it has?
Animals |
Number of legs |
A. Tick |
8 |
B. Spider |
6 |
C. Crab |
6 |
D. Praying mantis |
8 |
11. From the following groups of animals, choose the one that consists of reptiles only
A. Python, frog, millipede
B. Chameleon, crocodile, tortoise
C. Earthworm, snake, lizard
D. Newt, roundworms, salamander
12. Which one of the following groups of small animals consists of members with similar characteristics?
A. Bee, ladybird beetle, housefly.
B. Moth, tick, and ant.
C. Butterfly, spider, praying mantis.
D. Grasshopper, scorpion, termite.
13. Which one of the following is not a vertebrate?
A. Chameleon B. Rat C. Snail D. Lizard
14. Which one of the following animals is CORRECTLY MATCHED with its breathing organ?
Animal |
Breathing organs |
A. Whale |
Lungs |
B. Tilapia |
Nostrils |
C. Bat |
Spiracles |
D. Locust |
Skin |
15. The chart below shows the classification of small animals according to the number of legs.
Which animals are represented by P, Q, and R?
P |
Q |
R |
A. Bee |
Tick |
Centipede |
B. Grasshopper |
Wasp |
Caterpillar |
C. Mosquito |
Bedbug |
Sea urchin |
D. Butterfly |
Flea |
Millipede |
16. The classification chart below was used by some pupils to classify animals they had observed.
Into which one of the groups would they classify a frog?
17. Which one of the following animals is NOT CORRECTLY matched with its characteristics?
Animal |
Characteristics |
A. Frog |
Moist skin, lay eggs, varying body temperature |
B. Ostrich |
Feathers, lays eggs, constant body temperature |
C. Bat |
Hair, gives birth to young constant body temperature |
D. Snake |
Scales, lays egg, constant body temperature |