Free Biodiversity and Variety of Life MCQs with Answers

2761. Excretory system of platyhelminthes consists of which of the following?

• A. Nephridia
• B. Flame cells
• C. Malpighian tubules
• D. Nephron

Explanation: The excretory system of Platyhelminthes consists of flame cells because these specialized cells help remove metabolic waste from the body.Flame cells contain beating cilia that look like a flickering flame, which helps draw waste-containing fluid into the tubules.This fluid then moves through a network of ducts and exits through pores on the body surface.

2762. Garden snail belongs to which class of Mollusca?

• A. Gastropoda
• B. Cephalopoda
• C. Bivalvia
• D. None of these

Explanation: The garden snail is a part of the class Gastropoda within the phylum Mollusca. Gastropods are the largest group of mollusks and are known for their single, often spirally coiled shells. Snails, including the garden snail (Helix aspersa), are typical examples of this class. Cephalopoda, such as octopuses and squids, and Bivalvia, such as clams and mussels, belong to different classes within Mollusca and have distinct characteristics and structures. Myriapoda is not a class within Mollusca but is a subphylum under Arthropoda, which includes centipedes and millipedes.

2763. The internal buds are known as which of the following:

• A. Spicules
• B. Choanocytes
• C. Gemmules
• D. Both Options A and B are correct

Explanation: Spicules are the structural components of a sponge, or the "bricks," and the shapes, sizes, and composition are unique for each species.Choanocytes are the flagellated cell with a collar of protoplasm at the base of the flagellum, numbers of which line the internal chambers of sponges.Gemmules are a tough-coated dormant cluster of embryonic cells produced by a freshwater sponge for development in more favourable conditions.Therefore, option C is right choice here.

2764. A body cavity is absent in:

• A. Acoelomates
• B. Pseudococlomates
• C. Aeoclomates and Pscudocoelomates
• D. Coelomates

Explanation: Acoelomates are those animals in which there is no body cavity or space between body wall and digestive system. This group includes only one phylum Platyhelminthes.

2765. Division of labor is not seen in which of these multicellular animals?

• A. Hydra
• B. Euplectella
• C. Blood fluke
• D. Tapeworm
• E. A and b

Explanation: Hydra is another example of an animal that doesn't show division of labor. It has limited cell specialization and lacks distinct organs. Its cells work together to perform various functions.

2766. The skeleton of the sponges is in the form of variously shaped needle like structure called:

• A. Stipules
• B. Brails
• C. Spine
• D. Spicules

Explanation: Based on the explanations provided, the correct answer to the question is option D) Spicules.

2767. The name animal is derived from what word?

• A. Aname
• B. Anima
• C. Anemia
• D. None of these

Explanation: Yes, the word animal is derived from the Latin word anima, which means "breath, spirit, life". The word animal was first used in English in the 14th century, and it originally referred to any living creature. However, the meaning of the word has narrowed over time, and it now specifically refers to a living organism that is not a plant.The connection between the words animal and anima is that both words refer to the life force that animates living creatures. In Latin, the word anima was also used to refer to the soul, and this meaning is still preserved in some languages, such as French, where the word animal is also used to refer to the soul.

2768. Ascarisis characterized by which of the following?

• A. Presence of true coelom and metamerism
• B. Absence of true coelom and metamerism
• C. Presence of true coelom but the absence of metamerism
• D. Absence of true coelom but thepresence of metamerism

Explanation: Ascaris does not have a true coelom. Ascaris is an example of a pseudocoelomate organism. It possesses a pseudocoelom, which is a body cavity that is not entirely lined by mesoderm. This is in contrast to true coelomates, where the body cavity is completely lined by mesoderm.

2769. Mushrooms belong to the group of club fungi, have septate, and have a lengthy dikaryotic phase. What is the main phylum to which they belong?

• A. Zygomycota
• B. Basidiomycota
• C. Deuteromycota
• D. Ascomycota

Explanation: Mushrooms are classified under Basidiomycota, known as club fungi.

2770. Fungi absorb nutrients directly from the living host cytoplasm are called:

• A. Autotrophs
• B. Saprotrophs
• C. Parasites
• D. Predators

Explanation: Fungi that absorb nutrients directly from the living host cytoplasm are called Parasites. They harm the host by taking nutrients from its cells and often cause diseases. Unlike saprotrophs, they feed on living organisms instead of dead matter.