Free Kingdom Animalia MCQs with Answers

491. Which of the following is an incorrect difference between a Shark and a Whale?

• A. A shark's heart has only one chamber whereas a whale's heart has two chambers
• B. Shark gills are not covered by operculum whereas those in a whale are
• C. Sharks do not possess a swim bladder whereas whales do
• D. Sharks have placoid scales on their skin whereas whales don't

Explanation: OPTION A: The heart of a shark has two chambers: an atrium (also known as the auricle) and a ventricle. The heart of a whale heart has four chambers. There are two auricles and two ventricles. Hence, A is the correct option. OPTIONS B, C, and D have a correct difference between a shark and a whale.

492. Which of the following systems is well-developed in acoelomates?

• A. Excretory
• B. Nervous
• C. Transport
• D. Both options A and B are correct

Explanation: Acoelomates have complex nervous systems and excretory systems.

493. Sub-kingdom parazoa inlcudes:

• A. Annelida
• B. Cnidaria
• C. Porifera
• D. Protozoa

Explanation: Animals included in phylum Porifera are Parazoans because they do not show the formation of true tissues (except in class Hexactinellida).

494. Chitinous Setae are the locomotory organs of annelids which are present on?

• A. Cell wall
• B. Prostomium
• C. Nucleolus
• D. Parapodia

Explanation: The correct answer is d) Parapodia. Parapodia are fleshy, paddle-like structures that extend from the sides of the body segments in many annelids. They are specialized for locomotion, respiration, and sometimes serve as gills. Chitinous setae are present on the parapodia, and they play a crucial role in helping the annelids move through their environment by providing grip and traction.

495. Which is not a characteristic of triploblasts?

• A. They may be coelomate pseudocoelomate or acoelomate
• B. They are included in grade bilateria
• C. All of them have digestive systems
• D. All of them have blood vessels

Explanation: Triploblasts have three germ layers: the outer (ectoderm), inner (endoderm), and middle (mesoderm). This means that they are grade B bilaterians. They are further divided into acoelomate (no cavity), pseudocoelomate (false cavity-not in the middle), and coelomate (true cavity-formed by the splitting of mesoderm). They have a digestive system.

496. Typically, spiders' blood is blue due to the presence of which of the following?

• A. Haemoglobin
• B. Hemerythrin
• C. Haemocyanin
• D. Both Options B and C are correct

Explanation: Spider's blood is blue due to the presence of hemocyanin. Haemocyanin, instead of having an atom of iron in its middle, has an atom of copper that binds oxygen. It absorbs all colors except blue, which it reflects, making blood appear blue.

497. Which of the following statements about chordates is true?

• A. They are protostomes
• B. All chordates are vertebrates
• C. They lack a coelom
• D. Their anus forms from the blastopore

Explanation: Chordates are deustromes so the answer cannot be Option A. All vertebrates are chordates but not all chordates are vertebrates so the answer cannot be Option B. All chordates have a coelom so the answer cannot be Option C and their anus is formed first from blastopore so the answer is Option D.

498. Which of the following is a diploblastic organism?

• A. Hydra
• B. Crabs
• C. Squid
• D. Earthworm

Explanation: Diploblastic organisms have two germ layers, for example, Cridaria. Hydra belongs to the phylum Cridaria and class Hydrozoa.

499. Gut in pseudocoelomates is made from which of the following?

• A. Ectoderm
• B. Mesoderm
• C. Endoderm
• D. All of these

Explanation: The pseudocoelom in animals is derived from the blastocoel, which is the primary body cavity formed during embryonic development. The pseudocoelom is a fluid-filled cavity located between the mesoderm and endoderm germ layers. Unlike a true coelom, which is completely lined by mesoderm, the pseudocoelom is only partially lined by mesoderm. This distinction in embryonic development is important in understanding the classification of animals into coelomate, pseudocoelomate, and acoelomate categories.

500. The animals in which coelom is formed due to the splitting of the mesoderm are known as which of the following?

• A. Pseudocoelom
• B. Enterocoelous
• C. Amphicoelous
• D. Schizocoelous

Explanation: Option D is correct since in Schizocoelus organisms, coelom develops by splitting of the mesodermal embryonic tissue. Option A is incorrect because Pseudocoelom is one of the three types of Coelom not originated by the mesodermal epithelium. Option B is incorrect because, in Enteroceolus organisms, the coelom is formed by the pouches formed by the digestive tract. Option C is incorrect because Amphicoelous is a term used for vertebrae of certain fishes which is concave on both sides.