Free Biodiversity and Variety of Life MCQs with Answers

2971. Daphnia belongs to the class:

• A. Insecta
• B. Arachnida
• C. Myriapoda
• D. Crustacean

Explanation: Crustaceans form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. A crustacean has the following features: • a segmented body with a hard exterior (known as an exoskeleton) • jointed limbs, each often with two branches (termed biramous) • two pairs of antennae. • gills.

2972. The mammals terming connecting link between reptilian and mammals?

• A. Marsupials
• B. Eutherians
• C. Monotremes
• D. Metatherians

Explanation: Monotremes are considered the connecting link between reptiles and mammals because they exhibit both reptilian features, such as laying eggs, and mammalian features, like producing milk to feed their young. The platypus and echidna are examples of living monotremes. Marsupials, eutherians, and metatherians do not share this unique combination of reptilian and mammalian characteristics, making them incorrect answers.

2973. In which of the following book lungs are found?

• A. Clam worm
• B. Silver Fish
• C. Leach
• D. Spider

Explanation: book lung, form of respiratory organ found in certain air-breathing arachnid arthropods (scorpions and some spiders).

2974. Tissue organization is missing in protozoa and found in:

• A. Parazoa
• B. Metazoa
• C. Sporozoa
• D. Monera

Explanation: The correct answer is Sporozoa. Protozoa are unicellular organisms that lack tissue level organization, while Sporozoa specifically exhibit protoplasmic level organization without true tissues. Parazoa and Metazoa are multicellular but also lack true tissues, and Monera are primitive unicellular organisms without tissue level organization.

2975. Daphnia belongs to:

• A. Insecta
• B. Annelida
• C. Crustacean
• D. Arachinda

Explanation: Crustacean: This is the correct option. Daphnia belongs to the class Crustacea within the phylum Arthropoda. Crustaceans include various aquatic arthropods, such as crabs, lobsters, shrimp, and Daphnia, commonly known as water fleas. The other options are incorrect because Daphnia is not an insect (Option A), segmented worm (Option B), or arachnid (Option D). It is specifically classified as a crustacean within the phylum Arthropoda.

2976. Feathers of birds are water proof due to secretion of?

• A. Sudoriferous glands
• B. Endocrine glands
• C. Preen gland
• D. Thymus glands

Explanation: The correct answer is the preen gland. Birds use the preen oil secreted by the uropygial gland to waterproof their feathers. This oil helps maintain the integrity of the feathers and protects them from getting soaked, allowing birds to stay dry and maintain their ability to fly effectively. The other options, sudoriferous glands, endocrine glands, and thymus glands, do not play a role in waterproofing feathers.

2977. Which of the following is sedentary in adult and active in larval stage?

• A. Sponge
• B. Leech
• C. Salamander
• D. Grasshopper

Explanation: The correct answer is Sponge. Sponges have a sedentary adult stage where they are attached to a substratum, while their larval stages (Amphiblastula and Parenchymula) are free-living and active. Leeches, salamanders, and grasshoppers are all active in both their adult and larval stages, making them incorrect choices for this question.

2978. Which one is isotonic with surrounding sea water?

• A. Bony Fishes
• B. Shark
• C. Carp
• D. Paramecium

Explanation: Sharks are isotonic with sea water, meaning their body fluids have the same concentration of dissolved substances as the water. This allows them to maintain water balance easily. Bony fishes are hypotonic, needing to regulate their salt concentration. Carps are hypertonic in freshwater, while Paramecium is hypotonic due to lower solute concentration in the environment.

2979. Sperms of which animal can remain viable for years within the female genital tract?

• A. Whale
• B. Bat
• C. Camel
• D. Giraffe

Explanation: In most mammals, sperm is capable of fertilizing eggs for only a few days after copulation. Female bats have the ability to store sperm for extended periods, ranging from several months to even years, making them the correct answer in this context. Whales, camels, and giraffes do not exhibit the same level of sperm viability within the female genital tract as bats do.

2980. Opossum belongs to:

• A. Metatheria
• B. Eutheria
• C. Theria
• D. Prototheria

Explanation: Metatheria: Opossum belongs to the Metatheria, also known as marsupials. Marsupials are a group of mammals that give birth to relatively undeveloped young, which then complete their development in a pouch.Therefore, the correct option for opossum is 'Metatheria' as they belong to the marsupial group within the category of Theria. Eutheria, Theria, and Prototheria do not apply to opossums based on their classification characteristics.