Free Biodiversity and Variety of Life MCQs with Answers

991. Mytilus and Anodonta are example of which type of mollusca?

• A. Gastropods
• B. Bivalves
• C. Cephalopods
• D. None of the above

Explanation: Clams, mussels, oysters, and scallops, mytilus and anodonta are members to the class Bivalvia (or Pelecypodia). Bivalves have two shells, connected by a flexible ligament, which encase and shield the soft vulnerable parts of the creature. All 15,000 known species of bivalves are aquatic in nature, with close to 80% being marine (saltwater environments).Based on the explanations provided, the correct answer to the question is option B) Bivalves. Mytilus and Anodonta are examples of bivalve mollusks.

992. Euplectella belongs to phylum:

• A. Porifera
• B. Ctenophora
• C. Echinoderm
• D. None of the above

Explanation: Based on the explanations provided, the correct answer to the question is option A) Porifera. Euplectella belongs to the phylum Porifera.

993. All of the folloing are true for platyhelminthes except?

• A. Triploblastic
• B. Bilateral Symmetry
• C. Coelomate
• D. Flatworms

Explanation: Based on the explanations provided, the correct answer to the question is option C) Coelomate. Platyhelminthes are not coelomates.

994. The larvae of which of these animals resemble those of chordates?

• A. Starfish
• B. Cuttlefish
• C. Catfish
• D. Butterfly

Explanation: Based on the explanations provided, the correct answer to the question is option C) Catfish. Catfish larvae resemble the larvae of chordates to some extent.

995. Inner layers of the sponges are made up of which of the following?

• A. Pinacocytes
• B. Choanoderm
• C. Pinacoderm
• D. Choanocytes

Explanation: The inner layer of sponges is made up of choanocytes that are flagellated cells, this layer is called the choanoderm.

996. Lack of symmetry is identified in which group of animals?

• A. Protozoa
• B. Radiata
• C. Parazoa
• D. Coelomates

Explanation: Parazoa is a group of animals that lack true tissue organization and symmetry. This group includes organisms like sponges. These animals do not possess well-defined tissues or organs and exhibit a lack of symmetry, meaning they do not have a distinct bilateral or radial symmetry like more complex animals.

997. Midgut in cockroaches is a short narrow tube called which of the following?

• A. Hepatic caeca
• B. Rectum
• C. Stomach
• D. Gizzard

Explanation: The midgut in cockroaches is a short narrow tube called the "hepatic caeca." This structure is responsible for the secretion of digestive enzymes and the absorption of nutrients from food. The hepatic caeca help in breaking down complex molecules into simpler forms that can be absorbed by the cockroach's body.

998. Which of the following statement about chordates is true?

• A. They are protosomes
• B. All chordates are vertebrates
• C. They lack a coelom
• D. Their anus is formed from the blastopore

Explanation: Chordates, as deuterostomes, exhibit indeterminate cleavage and radial symmetry during their early embryonic development. In deuterostomes, the blastopore eventually develops into the anus, and a second opening called the mouth forms later.

999. Centipedes belong to class_of arthropoda.

• A. Arachnida
• B. Insect
• C. Cephalopoda
• D. Myriapoda

Explanation: Centipedes belong to the class Myriapoda within the phylum Arthropoda. This class includes centipedes and millipedes. Centipedes are elongated arthropods with one pair of legs per body segment, and they are known for their predatory nature.

1000. Which of the following animals is not a protostome?

• A. Cockroach
• B. Butterfly
• C. Stingray
• D. Earthworm

Explanation: Stingrays are cartilaginous fish and belong to the phylum Chordata. Chordates are deuterostomes, which means they have a mouth that develops from the second opening (the blastopore becomes the anus) during embryonic development. This makes them different from protostomes like insects.