Biology MCQs

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All the species listed are water-dwelling creatures. However, a fundamental difference is that fish belong to the group of vertebrates, meaning their body possesses a spinal column. In contrast, crabs, prawns, and snails are invertebrates, denoting that they lack a backbone. Specifically, crabs and prawns are crustaceans, within the larger class of invertebrates, characterised by their exoskeleton and segmented bodies. Snails are grouped as molluscs, also a class of invertebrates, known for their soft unsegmented body. Hence, in this context, fish are different from the others.

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When the body’s immune system cells destroy the insulin producing beta cells of the pancreas is termed as Type 1 diabetes. Symptoms may include increased thirst, frequent urination, hunger, fatigue and blurred vision.

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The gymnosperms, also known as Acrogymnospermae, are a group of seed-producing plants that includes conifers, cycads, Ginkgo, and gnetophytes. Pinus gerardiana, known as the chilgoza pine is a king of Gymnosperm.

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George W. Beadle (1903-1989) and Edward L. Tatum (1909-1975) show how genes direct the synthesis of enzymes that control metabolic processes. George Beadle and Edward Tatum were awarded Nobel Prize in 1958 for One Gene One Enzyme Concept.

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Pearls are composed primarily of calcium carbonate, which is what gives them their unique luster. They are formed within the shell of certain mollusks as a defense mechanism against a potentially threatening irritant, such as a parasite. Over time, the mollusk continually deposits layers of calcium carbonate, which eventually forms a smooth, hard pearl. This process can take up to eight years.

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The correct sequence of the evolution would be Monotremes, Marsupials and Eutheria. Since, Whale is in subclass Eutheria, it is the latest in the evolution. So the correct sequence is Echidena (Monotreme), Kangaroo (Marsupials) & Whale (Eutheria).Echidna  are the only surviving members of the Monotremata order and are the only living mammals that lay eggs.

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The least distance of distinct vision (LDDV) or the reference seeing distance (RSD) is the closest someone with “normal” vision (20/20 vision) can comfortably look at something. The range of vision of a healthy human eye is between it’s near point and far point i.e, from 25cm to infinity.

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The annelids (Annelida, from Latin anellus, “little ring”), also known as the ringed worms or segmented worms, are a large phylum, with over 22,000 extant species including ragworms, earthworms, and leeches.

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The vocal cord in women is about 15 mm long; in men vocal cords are about 20 mm long and children have very short vocal cords.