Free Kingdom Animalia MCQs with Answers

151. Animals of grade radiata are:

• A. Diploblastic
• B. Acoelomate
• C. Triploblastic
• D. Pscudococlomate

Explanation: Grade radiata includes only one phylum; Cnidaria. These animals are always diploblastic and have gastrovascular cavity with sac type digestive system.

152. Reproductive system arises from:

• A. Germlayer
• B. Ectoderm
• C. Mesoderm
• D. Endoderm

Explanation: Ectoderm form skin and nervous system. Endoderm form digestive system and rest of the systems in triploblastic animals are formed from mesoderm including reproductive system.

153. Reproductive system, excretory system, circulatory system and respiratory system developed from:

• A. Ectoderm
• B. Endoderm
• C. Mesoderm
• D. Ectoderm and endoderm

Explanation: Ectoderm forms skin and nervous system. Endoderm forms lining of digestive system and rest of the systems in triploblastic animals originate from mesoderm.

154. Bilaterally symmetrical animals are:

• A. Lesser developed
• B. Lacking mesoderm
• C. Placed in one phylum only
• D. Triploblastic

Explanation: All bilaterally symmetrical animals are triploblastic.

155. In coelomate the layer that surround endoderm is:

• A. Coelomic Epithelium
• B. Ectoderm
• C. Visceral mesoderm
• D. Parictal Mesoderm

Explanation: All bilateral symmetrical animals are triploblastic. Coelom (body cavity) is formed due to splitting of mesoderm at embryonic stages. Its outer layer is called parietal layer which underlines the body wall, while inner layer of mesoderm is called visceral layer that surrounds the endoderm.

156. All are correct about acoelomates except:

• A. Sac type digestive system
• B. Well-developed respiratory system
• C. Parenchyma till the body space
• D. Well-developed excretory system

Explanation: Acoelomate includes animals of Phylum Platyhelminthes in which respiratory and circulatory system is absent. Gaseous exchange takes place directly through body surface

157. Which of the following are pseudocoelomates?

• A. Platyhelminthes
• B. Echinoderms
• C. Molluscs
• D. Aschelminthes

Explanation: Aschelminthes or nematodes are pseudocoelomates.

158. A fluid filled cavity which is mesodermal in origin but absent in nematodes is:

• A. Coelom
• B. Gastrocoel
• C. Pseudocoelum
• D. Sponogocoel

Explanation: Coelom is true body cavity, which is always fonned from mesoderm. Nematodes are Pseudocoelomates

159. In acoelomates, gut is lined externally by:

• A. Visceral mesoderm
• B. Parietal mesoderm
• C. Splanchine mesoderm
• D. Endoderm

Explanation: The visceral mesoderm is a layer of the mesoderm in embryonic development that surrounds and supports the internal organs or viscera, including the heart, lungs, and digestive organs. It plays a vital role in the formation and development of these organs during embryogenesis, providing structural and functional support to ensure proper organ function.

160. Which system is more developed in acoelomates?

• A. Excretory system
• B. Respiratory system
• C. Digestive system
• D. Osmoregulatory system

Explanation: Acoelomate has sac type digestive system, no respiratory and osmoregulatory systems. They have tubular excretory system called protonephridia having flame cells.