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Chapter: 03. Kingdom Animalia

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Check Point 1

Give one word answer.
Animals without backbone.
Answer: Invertebrates
Animals having pores all over the body.
Answer: Poriferans (or Sponges)
Animals belonging to phylum platyhelminthes.
Answer: Flatworms
Animals having three pairs of legs.
Answer: Insects
Excretory organs of segmented worms.
Answer: Nephridia
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Check Point 2

Give one word answer. (Note: These questions are formatted as True/False statements in the curriculum.)
Aves is a class of aerial animals.
Answer: True
Crocodile lays eggs in water.
Answer: False (Crocodiles are reptiles and lay their eggs on land)
Parasites feed on animals only.
Answer: False (Parasites can also feed on plants and other hosts)
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Test Yourself

A. Multiple Choice Questions
Four-chambered heart is found in (a) Birds (b) Mammals © Amphibians (d) Birds and mammals
Answer: (d) Birds and mammals
Organs of locomotion in Arthropods are (a) Parapodia (b) Pseudopodia © Jointed legs (d) Wings
Answer: © Jointed legs
Vertebrates have (a) Tentacles (b) Hollow sac-like body © Flat body (d) Backbone
Answer: (d) Backbone
The earthworm is a/an (a) Poriferan (b) Annelid © Mollusc (d) Protozoan
Answer: (b) Annelid
Animals that have hair and feed their young ones with milk are called (a) Molluscs (b) Amphibians © Aves (d) Mammals
Answer: (d) Mammals
Tentacles are present in (a) Hydra (b) Tapeworm © Cockroach (d) Starfish
Answer: (a) Hydra
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B. Assertion-Reason Type Questions
In the questions given below, there are two statements marked as Assertion [A] and Reason [R]. Read the statements and choose the correct option for each. (a) Both Assertion [A] and Reason [R] are true. (b) Both Assertion [A] and Reason [R] are false. © Assertion [A] is true but Reason [R] is false. (d) Assertion [A] is false but Reason [R] is true.
Assertion [A]: Annelids have long, cylindrical and segmented body. ​Reason [R]: Annelids have nephridia for excretion.
Answer: (a) Both Assertion [A] and Reason [R] are true.
Assertion [A]: Insects have their body divided into head, thorax and abdomen. ​Reason [R]: The insects have three pairs of legs.
Answer: (a) Both Assertion [A] and Reason [R] are true.
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C. Fill in the blanks with suitable words.
________ are soft-bodied animals with shell.
Answer: Molluscs
Invertebrates with jointed legs are called ________.
Answer: Arthropods
Centipede and millipede are examples of ________.
Answer: Myriapods
________ are vertebrates which spend life on land but reproduce in water.
Answer: Amphibians
________ have hair on their skin and nourish their young ones with their milk.
Answer: Mammals
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D. State whether these statements are true or false. If false, rewrite the correct form of statements.
Roundworm and earthworm belong to the same group.
Answer: False. Roundworms belong to Nematoda (Nemathelminthes), whereas earthworms belong to Annelida.
Spiders, bedbug and butterfly are all arthropods.
Answer: True.
Sponge is an example of segmented animals.
Answer: False. Sponge is an example of unsegmented, pore-bearing animals belonging to phylum Porifera.
Arachnids have eight legs but no wings.
Answer: True.
Leech is an example of segmented animals.
Answer: True.
Starfish is a vertebrate.
Answer: False. Starfish is an invertebrate belonging to phylum Echinodermata.
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E. Give one word for each of the following.
Animals that form corals
Answer: Coelenterates (or Cnidarians)
Animals with three pairs of jointed legs and two pairs of wings
Answer: Insects
Animals without backbone
Answer: Invertebrates
Animals that can live both on land and in water
Answer: Amphibians
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F. Give reasons for the following.
Whales and Dolphins appear like fish and live in water but are grouped with mammals.
Answer: Whales and dolphins are grouped with mammals because they are warm-blooded, breathe air through lungs, give birth to live young ones, and females possess mammary glands to feed milk to their young.
Kangaroo keeps her young ones in an abdominal pouch.
Answer: Female kangaroos give birth to highly premature (undeveloped) young ones, keeping them inside an abdominal pouch (marsupium) where they can feed on mother’s milk, stay protected, and complete their development safely.
Earthworms are called farmer’s friends.
Answer: The burrowing and soil-feeding habits of earthworms loosen the soil and make it porous. This increases soil aeration and water absorption, making the soil highly fertile.
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G. Encircle the odd one out. Give reasons for your choice.
Paramecium, Amoeba, Euglena, Bacteria
Answer: Bacteria. Reason: Bacteria is a prokaryotic organism, while Paramecium, Amoeba, and Euglena are eukaryotic organisms (protists).
Horse, Cow, Goat, Snake
Answer: Snake. Reason: Snake is a cold-blooded, egg-laying reptile with scales, whereas horses, cows, and goats are warm-blooded, milk-producing mammals with hair.
Crow, Owl, Sparrow, Frog
Answer: Frog. Reason: Frog is an amphibian, while crow, owl, and sparrow are birds (class Aves).
Shark, Seahorse, Carp, Salamander
Answer: Salamander. Reason: Salamander is an amphibian (class Amphibia), while shark, seahorse, and carp are fishes (class Pisces).
Cockroach, Spider, Butterfly, Mosquito
Answer: Spider. Reason: Spider is an arachnid with eight legs and no wings, while cockroach, butterfly, and mosquito are insects with six legs and wings.
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H. Differentiate between the following.
Vertebrates and Invertebrates
Answer:
Vertebrates: Possess a backbone or vertebral column, have an internal bony skeleton, usually possess a tail, and have exactly two pairs of limbs (e.g., human, fish).
Invertebrates: Lack a backbone or vertebral column, lack an internal bony skeleton, lack a true tail, and their limbs are either absent or present in multiple pairs (e.g., earthworm, cockroach).
Roundworm and Tapeworm
Answer:
Roundworm (Nematoda): Has a long, cylindrical, and unsegmented body (e.g., Ascaris).
Tapeworm (Platyhelminthes): Has a thin, soft, flattened, ribbon-like, and segmented body (e.g., Tapeworm).
Frog and Lizard
Answer:
Frog (Amphibia): Has a slimy, slippery skin, lives in both water and land, breathes through skin (in water) and lungs (on land), and lays eggs in water.
Lizard (Reptilia): Has dry, scaly skin, lives mostly on land, breathes exclusively through lungs, and lays leathery eggs on land.
Bird and Bat
Answer:
Bird (Aves): Has a body covered with feathers, possesses a horny toothless beak, and reproduces by laying hard-shelled eggs.
Bat (Mammalia): Has a body covered with hair, possesses teeth and external ears, and gives birth to live young ones, feeding them with milk.
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I. Match the columns.
Column A
Column B
1. Bag-like body with tentacles around the opening
(a) Pisces
2. Body with small pores all over
(b) Coelenterata
3. Two-chambered heart
© Echinodermata
4. Spiny skinned animals with star-shaped body
(d) Arthropoda
5. Animals with jointed legs
(e) Porifera
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Answer:
1 matches with (b) Coelenterata
2 matches with (e) Porifera
3 matches with (a) Pisces
4 matches with © Echinodermata
5 matches with (d) Arthropoda
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J. Answer these questions.
Name different classes of vertebrate animals with one example of each.
Answer: The five classes of vertebrates and their examples are:
Pisces (Fishes): Rohu (or Shark)
Amphibia: Frog (or Salamander)
Reptilia: Lizard (or Snake)
Aves (Birds): Sparrow (or Pigeon)
Mammalia: Elephant (or Tiger)
How are fish different from amphibians?
Answer: Fishes live exclusively in water, possess a streamlined body covered with scales, breathe using gills, swim with fins, and have a two-chambered heart. Amphibians can live on both land and in water, have slippery/slimy skin without scales, possess two pairs of limbs, breathe through lungs (on land) or skin (in water), and have a three-chambered heart.
Give two main features of mammals?
Answer: Two main features of mammals are:
Their body is covered with hair.
Females have mammary glands that produce milk to nourish their young ones.
Write short notes on: (a) Flatworms (b) Arthropods © Reptiles (d) Mammals
Answer:
(a) Flatworms: Belonging to phylum Platyhelminthes, they have thin, soft, and flattened bodies without a body cavity. They are often divided into segments and mostly live as parasites inside the bodies of host animals (e.g., Tapeworm, Liverfluke).
(b) Arthropods: This is the largest group of invertebrates. Their bodies are covered by a hard chitinous exoskeleton, divided into head, thorax, and abdomen, and they possess paired, jointed legs (e.g., Cockroach, Prawn).
© Reptiles: They are cold-blooded land vertebrates with dry, scaly skin and clawed digits. They breathe through lungs, have a three-chambered heart (four in crocodiles), and lay leathery, yolky eggs on land (e.g., Snake, Crocodile).
(d) Mammals: They are warm-blooded, milk-producing vertebrates with bodies covered in hair and projecting external ears. They have a four-chambered heart, breathe through lungs, and give birth to fully formed young ones (e.g., Human, Elephant).
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