Free Kingdom Animalia MCQs with Answers

31. Which one of the following statements about certain given animals is correct?

• A. Roundworms (Aschelminthes) are pseudocoelomates
• B. Molluses are acoelomates
• C. Insects are pseudocoelomates
• D. Flatworms (Platyhelminthes) are coelomates

Explanation: Roundworms, or Aschelminthes, are indeed pseudocoelomates. They have a body cavity called a pseudocoelom that is partially lined with mesoderm, unlike true coelomates where the coelom is entirely surrounded by mesoderm. This pseudocoelom provides some space for organ development and circulation of fluids.

32. Crocodile and penguin are similar to whale and dogfish in which one of the following features?

• A. Possess a solid single stranded central nervous system
• B. Lay eggs and guard them till they hatch
• C. Possess bony skeleton
• D. Have gill slits at some stage

Explanation: Animals belonging to Phylum Chordata are fundamentally characterised by the presence of a notochord, a dorsal hollow nerve cord and paired pharyngeal gill slits. Crocodile, penguin, whale and dogfish are all chordates. All of them have gill slits or have had them during embryonic development. Thus, paired gill slits are present in these animals at some stage of life.

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

• A. Aschelminthes (round worms)
• B. Ctenophores
• C. Sponges
• D. Coelenterates (cnidarians)

Explanation: Aschelminthes is a superphylum consisting of pseudocoelomates. These are mostly aquatic, free living or parasitic. Their body is slender, bilaterally symmetrical and triploblastic.

34. If a live earthworm is pricked with a needle on its outer surface without damaging its gut, the fluid that comes out is:

• A. Coelomic fluid
• B. Haemolymph
• C. Slimy mucus
• D. Excretory fluid

Explanation: Coelom or body cavity of earthworm is filled with coelomic fluid. It lies between body wall and alimentary canal. So if a live earthworm is pricked with a needle on its outer surface without damaging the gut then only coelomic fluid will come out.

35. Which one of the following pairs of animals comprise 'jawless fishes'?

• A. Mackerals and rohu
• B. Lampreys and hag fishes
• C. Guppies and hag fishes
• D. Lampreys and eels

Explanation: Agnatha is subphylum or superclass of marine and fresh water vertebrates that lack jaws. They are fishlike animals with cartilaginous skeletons and well developed sucking mouthparts with horny teeth. The only living agnathans are lampreys and hagfishes (Class Cyclostomata), which are parasites or scavengers.

36. Which one of the following indicates reptilian ancestry in birds?

• A. Two special chambers crop and gizzard in their digestive tract
• B. Eggs with a calcareous shell
• C. Scales on their hind limbs
• D. Four chambered heart

Explanation: Yes, both birds and reptiles lay eggs with a calcareous (calcium carbonate) shell, which provides protection and allows for gas exchange during embryonic development.

37. Ascaris is characterized by:

• A. Presence of true coelom but absence of metamerism
• B. Presence of true coelom and metamerism (metamerisation)
• C. Absence of true coelom but presence of metamerism
• D. Presence of neither true coelom nor metamerism

Explanation: Ascaris belong to the Phylum Nematoda of Superphylum Aschelminthes.They have a cylindrical body without showing any metamerism, a pseudocoelom (false coelom) and a complete digestive tract lined by endodermal epithelium. The cuticle covering the body surface bears minute transverse striations giving a pseudosegmented appearance to the worm.

38. Which one of the following pairs of items correctly belongs to the category of organs mentioned against it?

• A. Nephridia of earthworm and Malpighian tubules of cockroach - excretory organs
• B. Wings of honey bee and wings of crow - homologous organs
• C. Thorn of Bougainvillea and tendrils of Cucurbita - analogous organs
• D. Nictitating membrane and blind spot in human eye - vestigial organs

Explanation: Nephridia are excretory organs of the earthworm which consist of a simple or branched tube formed by the ingrowth of ectoderm with cilia at the inner end. Excretory products diffuse into the nephridium and are wafted to the exterior by ciliary action. Malpighian tubules are the organs that are involved in the excretion of nitrogenous wastes in cockroach. They open into the intestine and selectively extract Uric acid from the blood. The acid, together with water and salts, is deposited into the hindgut and excreted in the faeces.

39. Which one of the following phyla is correctly matched with its two general characteristics?

• A. Echinodermata - pentamerous radial symmetry and mostly internal fertilization
• B. Mollusca - normally oviparous and development through a trochophore or veliger larva
• C. Arthropoda - body divided into head, thorax and abdomen and respiration by tracheae
• D. Chordata - notochord at some stage and separate anal and urinary openings to the outside

Explanation: Arthropods are the largest phylum of Kingdom Animalia that characteristically possesses an outer body layer - the cuticle. Their body is composed of segments usually forming distinct specialized body regions, i.e., head, thorax and abdomen. In them the trachea or windpipe or book lungs are the respiratory organs found in terrestrial forms, which help in respiration.

40. Which one of the following is not a characteristic of Phylum Annelida?

• A. Pseudocoelom
• B. Ventral nerve cord
• C. Closed circulatory system
• D. Segmentation

Explanation: Phylum Annelida comprises invertebrates, which are segmented worms having cylindrical soft bodies showing metameric segmentation. These are triploblastic animals showing bilateral symmetry. A true coelom is present which is filled with coelomic fluid containing cells. Annelids are perhaps the first animals to have a true schizocoelic coelom.