Free Biodiversity and Variety of Life MCQs with Answers

1451. Reptiles become successful terrestrial vertebrates mainly due to the evolution of:

• A. Amniotic eggs
• B. Moveable eyelids
• C. Joined jaw bones
• D. Three chambered heart

Explanation: Amniotic eggs that can withstand dessication allowed reptiles to reproduce on land and lead to successful inhabitation of land. Option A is correct.

1452. The feature of birds which is NOT considered as a flight adaptation is that their:

• A. Body is covered by feathers
• B. Eggs are protected by shells
• C. Bones are hollow and light in weight
• D. Anterior limbs are modified into wings

Explanation: The correct answer is (Option B) that the protection of eggs by shells is not a flight adaptation in birds.The primary function of eggshells is to protect the developing embryo from the external environment and predators.

1453. The given diagram shows two specimen of class amphibia. Specimen I is a toad.In contrast to specimen II (frog), specimen I (toad) has:

• A. Webbed feet
• B. Protruding eyes
• C. Longer legs for hopping
• D. Stout and chubby body shape

Explanation: Specimen I, identified as a toad, typically exhibits a stout and chubby body shape. This is in contrast to frogs, which are generally more slender and have longer legs, suited for jumping or hopping. Toads often have shorter legs, which result in more of a walking movement. Additionally, toads tend to have dry, warty skin compared to the smooth, moist skin of frogs.

1454. The given image shows a specimen.It is identified as:

• A. Hydra
• B. Star fish
• C. Jelly fish
• D. Brittle star

Explanation: Brittle star has thin, slender arms attached to a distinct central disc. The specimen given is a brittle star. So option D is correct.

1455. An animal in which food is completely digested in the gut is

• A. Hydra
• B. Amoeba
• C. Planaria
• D. Cockroach

Explanation: The correct answer is the cockroach. Cockroaches possess a well-developed digestive system with a mouth, esophagus, crop, gizzard, stomach, intestine, and anus, allowing for complete digestion of food in the gut. In contrast, hydras and planaria have simpler digestive systems where food is not fully digested, and amoebas digest food intracellularly, which is not complete digestion within a gut.

1456. An example of endoparasite in animals is:

• A. Lice
• B. Ticks
• C. Leech
• D. Tapeworm

Explanation: Tapeworms are classified as endoparasites because they reside within the internal organs, specifically the intestines, of their host organisms. They absorb nutrients through their skin from the host's digested food.

1457. The given diagram represents body tissue organisation of a:

• A. Triploblastic coelomate
• B. Diploblastic acoelomate
• C. Triploblastic acoelomate
• D. Triploblastic pseudocoelomate

Explanation: It's triploblastic, as all three germ layers are present and pseudoceolomate. In a pseudocoelom, the mesoderm lines only one side of the cavity, with the other side being lined by endoderm.So D is correct.

1458. The invertebrate which has a closed circulatory system is:

• A. Flatworm
• B. Pinworm
• C. Earthworm
• D. Hookworm

Explanation: The correct answer is the earthworm. Earthworms are annelids, which are known to have a closed circulatory system where the blood is enclosed within vessels and circulates throughout the body. This system is efficient for transporting nutrients and oxygen to various body parts.

1459. An example of a free-living, non-parasitic flat worm is:

• A. Planaria
• B. Tapeworm
• C. Liver fluke
• D. Blood fluke

Explanation: The correct answer is Planaria. Planaria are free-living, non-parasitic flatworms commonly found in freshwater environments. They are known for their remarkable ability to regenerate.

1460. The animal which has a gut with single opening is:

• A. Planaria
• B. Cockroach
• C. Earthworm
• D. Roundworm

Explanation: The correct answer is Planaria. Planaria are flatworms with a digestive system that consists of a single opening, known as a gastrovascular cavity, serving both as an entry for food and an exit for waste. This is a characteristic of simpler, more primitive organisms.