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Q1. In which phylum, the body is segmented?

• Porifera
• Coelenterata
• Annelida
• Mollusca

Solution

Annelids show metameric segmentation. The body is segmented externally and internally into a number of segments.

Q2. Flame cells are the excretory organs in  

• Planaria  
• Hydra  
• Hydrilla  
• Cockroach  

Solution

Flame cells are found only in organisms which belong to the phylum Platyhelminthes (Planaria belongs to class Turbellaria). A flame cell is a hollow cell containing a tuft of cilia or flagella. This cell beats incessantly and resembles a flickering cell; hence, it is called a flame cell. Flame cells play a role in excretion and osmoregulation.  

Q3. In molluscs, the eye is present over a stalk called  

• Ostracum  
• Operculum  
• Ommatophores  
• Osphradium  

Solution

Ommatophores  

Q4. Bioluminescence is commonly seen in 

• Annelida
• Ctenophora
• Echinodermata
• Porifera

Solution

Bioluminescence is the production of light with very little heat by a chemical reaction within an organism. This is seen in ctenophores such as comb jellies. 

Q5. The simplest type of canal system in Porifera is the 

• Ascon type
• Leucon type
• Sycon type
• Radial type

Solution

The simplest type of canal system in Porifera is the ascon type. 

Q6. Metameric segmentation is the main feature of  

• Annelida  
• Echinodermata  
• Arthropoda  
• Coelenterata  

Solution

Metameric segmentation is true segmentation in which external segmentation corresponds to the internal segmentation and the body is divided into a number of segments.  

Q7. Animal without the larval stage or metamorphosis is

• Asterias
• Musca domestica
• Pheretima posthuma
• Butterfly

Solution

Pheretima posthuma, the common name is earthworm, does not have any larval stage in its life cycle.

Q8. Coelom is a cavity between the body wall and the alimentary canal and is lined by  

• Ectoderm and endoderm  
• Ectoderm and mesoderm  
• Ectoderm on both sides  
• Mesoderm on both sides  

Solution

The body wall and the alimentary canal both are lined by the mesoderm, which means the coelom body cavity is lined by the mesoderm on either side.  

Q9. Which of the following group of animals maintains high and constant body temperature such as mammals?

• Reptiles
• Amphibians
• Birds
• Fish

Solution

Birds are homeothermic. Homeotherms are the animals which maintain high and constant body temperature independent of the temperature of the external environment.

Q10. The silverfish Lepisma is  

• Fish  
• Mammal  
• Echinoderm  
• Insect/arthropod  

Solution

Lepisma (silverfish) belongs to the insect class under phylum Arthropoda.  

Q11. In which triploblastic animal, coelom is absent?

• Platyhelminthes
• Aschelminthes
• Annelids
• Arthropods

Solution

In Platyhelminthes, endoderm, ectoderm and mesoderm are present. However, the mesoderm is present patched between the endoderm and the ectoderm, and it does not line the gut.

Q12. What is common between parrot, platypus and kangaroo?  

• Toothless jaws  
• Functional post-anal tail  
• Oviparity  
• Homoiothermy  

Solution

Parrot, platypus and kangaroo are mammals. Homoiothermy is the common feature seen in these three animals. Homoiothermy is the phenomenon in which animals maintain constant, high body temperature irrespective of the temperature of the external environment.  

Q13. Ambulacral grooves are absent in the class  

• Asteroidea  
• Crinoidea  
• Ophiuroidea  
• None of these  

Solution

Ambulacral grooves are deep grooves present on the oral surface in echinoderms. These grooves extend from the mouth to the end of each arm. Each groove bears rows of tube feet. In class Ophiuroidea, the ambulacral grooves are absent. Example: Sea urchin  

Q14. In contrast to Annelids, the Platyhelminthes show

• Absence of body cavity
• Bilateral symmetry
• Radial symmetry
• Presence of pseudocoel

Solution

Annelids are coelomates, while platyhelminthes are acoelomates, i.e. the body cavity is absent.

Q15. Leech secretes which of the following anticoagulants?  

• Hirudin  
• Heparin  
• Serotonin  
• Histamine  

Solution

Leech secretes hirudin (anticoagulant) which prevents the clotting of host’s blood at the time of feeding.  

Q16. Order Primata contains

• Shrew and hedgehog
• Bat and flying fox
• Monkey and man
• Horse and zebra

Solution

Monkey and man belong to order Primata.

Q17. Sea snakes are  

• Oviparous  
• Viviparous  
• Ovoviviparous  
• Parthenogenetic  

Solution

Sea snakes belong to class Reptilia. Most of the reptiles are oviparous, but some reptiles exhibit ovoviviparity or viviparity. Oviparous animals lay eggs, viviparous animals give birth to young ones, while in ovoviviparous animals, the embryo develops in the egg inside the mother’s body until it is ready to hatch.  

Q18. Match the incorrect pair.

• Pediculus - typhus
• Xenopsylla - plague
• Culex - malaria
• Aedes - yellow fever

Solution

Culex mosquito spreads filariasis or elephantiasis. Anopheles mosquito spreads malaria.

Q19. Notochord is present in

• All chordates
• Few chordates
• All vertebrates
• Few vertebrates

Solution

Dorsal, rod-like notochord is the primary feature of all chordates. Based on this feature, all animals which show the presence of notochord are grouped under the phylum Chordata.

Q20. Ichthyophis is a  

• Limbless amphibian  
• Limbless reptile  
• Worm  
• Limbless mammal  

Solution

Ichthyophis is a burrowing amphibian. Because of their burrowing habit, they have lost their limbs and even their eyes are degenerated.  

Q21. Daphnia is commonly known as  

• clam shrimp  
• fairy shrimp  
• water fleas  
• tadpole shrimp  

Solution

Daphnia are called water fleas because their swimming style resembles the movement of fleas.  

Q22. Spermathecae in earthworm is  

• For producing sperm  
• For storage of sperm obtained from the male worm during copulation and used in the future  
• Both 1 and 2 above  
• None of these  

Solution

Four pairs of spermathecae are present in the 6^th, 7^th, 8^th and 9^th segments. They open on the ventral side. Spermathecae receive and store sperms during copulation.  

Q23. Which of the following have a notochord throughout life?

• Birds
• Fish
• Snake
• Amphioxus

Solution

Amphioxus belongs to the phylum Chordata (subphylum Cephalochordata). In amphioxus, the notochord persists throughout life. In chordates which belong to the subphylum Vertebrata, the notochord develops into the vertebral column during embryonic development.

Q24. Which animals have larval stages?  

• Cockroach and honeybee  
• Grasshopper and dragonfly  
• Housefly and butterfly  
• Cockroach and housefly  

Solution

The larva of housefly is called maggot, and the larva of butterfly is called caterpillar.  

Q25. Carapace is present on the dorsal surface of  

• Elephant  
• Tortoise  
• Python  
• Alligator  

Solution

The dorsal plate of the protective bony shell which encloses the body is called carapace. It is found in reptiles such as turtles, tortoises, terrapins etc.  

Q26. Which of the following coelenterates does not exhibit alternation of generation in its life cycle?

• Obelia
• Hydra
• Aurelia
• Physalia

Solution

Hydra does not show alternation of generation in its life cycle. It also does not have any larval stage during its life cycle.

Q27. Haemocoel is found in

• Arthropoda
• Coelenterata
• Porifera
• Annelida

Solution

In arthropods, the body cavity is filled with blood, and hence, it is known as haemocoel.

Q28. Gambusia is a

• Pest of fishes
• Parasitic fish
• Predator of mosquito larvae
• Yellow fever mosquito

Solution

Gambusia feeds on larvae of insects. They also thrive in shallow and stagnant waters. Therefore, they are used as a mosquito control agent.

Q29. Which one of the following groups of animals is bilaterally symmetrical and triploblastic?  

• Coelenterates (Cnidarians)  
• Aschelminthes (Roundworm)  
• Ctenophores  
• Sponges  

Solution

Aschelminthes (Roundworm) is triploblastic, and it is bilaterally symmetrical.  

Q30. Which of the following pairs are correctly matched?   Sr. No.  Animals  Morphological features  (i)  Crocodile  4-chambered heart  (ii)  Sea urchin   Parapodia  (iii)  Obelia  Metagenesis  (iv)  Lemur  Thecodont   

• (ii), (iii) and (iv)
• Only (i) and (iv)
• Only (i) and (ii)
• (i), (iii) and (iv)

Solution

Crocodile is a reptile and it has a four-chambered heart. Obelia belongs to the phylum Cnidaria. The cnidarian life cycle shows alteration of generations between polyps and medusae. This is called metagenesis. Lemur is a mammal. All mammals are thecodonts, i.e. teeth are embedded in sockets in the jaws.

Q31. An animal which lacks a larva in its life cycle is

• Earthworm
• Prawn
• Crab
• Cockroach

Solution

In earthworm, the development is direct.

Q32. Which of the following is the free swimming larva of coelenterates?  

• Planula  
• Trochophore  
• There is no larval stage in the life cycle of coelenterates  
• Amphiblastula  

Solution

In coelenterates, the zygote forms the planula larva which swims, settles and grows into a sessile polyp.  

Q33. Long hollow bones with interconnected air passages are characteristic of

• Reptiles
• Aves
• Mammals
• All land vertebrates

Solution

Long hollow bones with interconnected air passages are characteristic of Aves. These features help birds in easy flight.

Q34. Poison gland of a snake is the modified  

• Parotid gland  
• Sublingual gland  
• Maxillary gland  
• Lingual gland  

Solution

The parotid glands are modified into poison glands in snakes.  

Q35. Radial symmetry is observed in  

• Platyhelminthes  
• Coelenterates  
• Aschelminthes  
• Annelids  
• Echinoderms  

Solution

In radial symmetry, any plane passing through the central axis of the body divides the organism into equal halves.  

Q36. Metameric segmentation is the characteristic of  

• Mollusca and Chordata  
• Platyhelminthes and Arthropoda  
• Echinodennata and Annelida  
• Annelida and Arthropoda  

Solution

Metameric segmentation is true segmentation in which external segmentation corresponds to the internal segmentation and the body is divided into a number of segments. Animals which belong to phyla Annelida and Arthropoda exhibit metameric segmentation.  

Q37. Classification of Porifera is based on 

• Branching
• Spicules
• Reproduction
• Symmetry

Solution

Classification of Porifera is based on the skeleton, i.e. spicules. 

Q38. Sponges are evolved from

• Ciliates
• Choanoflagellates
• Protozoans
• Flagellates

Solution

Sponges have evolved from flagellates. They resemble the flagellates in having the flagellated collar cells and intracellular digestion. The larva amphiblastula also resembles the flagellates.

Q39. Which of the following organisms have a loose mantle over their body?  

• Echinoderms  
• Molluscs  
• Platyhelminthes  
• Mammals  

Solution

The mantle is a thick, muscular fold of the body wall. It protects the internal body organs.  

Q40. In contrast to the Annelids, the Platyhelminthes show:  

• Radial symmetry  
• Presence of pseudocoel  
• Bilateral symmetry  
• Absence of body cavity