Free Biodiversity and Variety of Life MCQs with Answers

1181. The skeleton of sponges is made up of which of the following?:

• A. Calcium
• B. Silica
• C. Both A and B
• D. None of these

Explanation: The skeletal structures of sponges are spicules and spongin fibres. Spicules are formed by carbonates of lime or silica in the form of needle-like pieces so, calcium and silica both are correct.

1182. The lungs of lungfish are thought to have evolved from _.

• A. The swimbladder of cartilaginous fish
• B. The swimbladder of bony fish
• C. The swimbladder of lobe-finned fish
• D. They evolved independently

Explanation: Lungfish have lungs that are derived from the swim bladder (an organ used for buoyancy in most bony fishes), which is connected to the alimentary tract.

1183. Sycon is an example of:

• A. Platyhelminthes
• B. Annelids
• C. Protozoa
• D. Porifera

Explanation: Sycon is an example of Porifera. Porifera is a phylum of animals that are also known as sponges. Sponges are simple animals that do not have a body cavity or organs. They are filter feeders, meaning that they obtain their food by filtering water through their bodies.

1184. Which of the following use book lungs to breathe?

• A. Earthworm
• B. Scorpions
• C. Fish
• D. All of these

Explanation: Scorpions use structures known as book lungs for respiration. Book lungs are respiratory organs found in various arachnids, including scorpions. These specialized structures consist of thin layers of tissue arranged like the pages of a book.

1185. Second largest phylum of invertebrates is which of the following?

• A. Porifera
• B. Arthropoda
• C. Chordata
• D. Mollusca

Explanation: The second largest phylum of invertebrates is the Mollusca. Molluscs are a diverse group of animals that includes snails, clams, octopuses, and squid, among others. The phylum Mollusca is characterized by a soft body, often protected by a hard shell and a muscular foot used for locomotion. They also have a specialized feeding structure called a radula, and some molluscs have well-developed heads and complex nervous systems. The largest phylum of invertebrates is Arthropoda, which includes insects, spiders, crustaceans, and other related animals.

1186. Notochord occurs throughout life and all through the length of the body in which of the following?

• A. Hemichordata
• B. Urochordata
• C. Vertebrata
• D. Cephalochordata

Explanation: Notochord code occurs throughout life and all through the length of the body in cephalochordates.

1187. Which group does not contain polyp?

• A. Anthozoa
• B. Hydrozoa
• C. Scyphozoa
• D. Calcerea

Explanation: Calcarea is a group that does not contain polyps. Calcarea is a subclass of the phylum Porifera, which includes sponges. Sponges are not part of the Cnidaria, the phylum that includes anthozoans, hydrozoans, and scyphozoans, which all have polyp and/or medusa body forms. Anthozoans, for example, are a class of Cnidarians that include corals and sea anemones, which have a polyp body form. Hydrozoans and scyphozoans have both polyp and medusa body forms at different stages of their life cycles.

1188. Coelom is lined by which of the following?

• A. Parietal mesoderm
• B. Visceral mesoderm
• C. Mesoderm
• D. Both a and b

Explanation: Coelom is a fluid-filled cavity lined by a mesodermal epithelium called mesothelium. It is surrounded by two layers of mesoderm: the parietal mesoderm that lines the body wall and the visceral mesoderm that covers the organs. The mesothelial cells secrete a serous fluid that fills the coelom and allows the organs to move freely.

1189. Pinworm is a common name used for which of the following?

• A. Rhabditis
• B. Ancylostoma duodenale
• C. Taenia solium
• D. Enterobius vermicularis

Explanation: Pinworm is a common name for Enterobius Vermicularis.

1190. A jawless fish lays eggs in fresh water and its ammocoetes larvae after metamorphosis. This fish returns to the ocean as _.

• A. Neomyxine
• B. Petromyzon
• C. Eptatretus
• D. Myxine

Explanation: The jawless fish that lays eggs in fresh water and its ammocoetes larvae after metamorphosis and returns to the ocean is Petromyzon. It is also known as the sea lamprey. Petromyzon is a member of the class Cyclostomata, which includes all jawless fish. The life cycle of Petromyzon begins with the adults spawning in freshwater. The eggs hatch into ammocoetes larvae, which live in freshwater for several years. After metamorphosis, the young lampreys migrate to the ocean, where they live for the rest of their lives.