Biology MCQs

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Calcitriol is the biologically active form of Vitamin D. It is normally made in the kidney. It is used to treat diseases like hypoparathyroidism, osteoporosis, osteomalacia, and familial hypophosphatemia.

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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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Calcium is required in plants in the formation of cell wall. It is a structural layer surrounding some types of cells, just outside the cell membrane. The cell wall can be tough, flexible, and sometimes rigid also.

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A halophyte is a salt-tolerant plant that grows in soil or waters of high salinity. They consists of pneumatophores which are negatively geotropic roots which grow upward & meant for gaseous exchange.

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Defensin-1 is the name of a protein, which has the property of resistance of epithelial surfaces to microbial colonization. This protein has the potential to develop drugs for antibiotic resistant bacteria. Honey bees make this protein and adds to honey and the scientists at the Academic Medical Centre, Amsterdam say that one day the drugs developed by Honey containing Defensin-1 , could combat antibiotic-resistant infections.

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Correct answer is beta-amylase. Regarding amylase there is an interesting fact that it has proved its role in Human evolution. The salivary amylase levels found in the human lineage are six to eight times higher in humans than in chimpanzees, which are mostly fruit eaters and ingest little starch relative to humans.

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Glaucoma is an eye disease that is often associated with elevated intraocular pressure, in which damage to the eye (optic) nerve can lead to loss of vision and even blindness.

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Mycoplasma genitalium, a parasitic bacterium which lives in the primate bladder, waste disposal organs, genital, and respiratory tracts, is thought to be the smallest known organism capable of independent growth and reproduction.

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Plants have only three tissue types: 1) Dermal; 2) Ground; and 3) Vascular. These tissues can be simple, consisting of a single cell type, or complex, consisting of more than one cell type.

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Color blindness occurs when light-sensitive cells in the retina fail to respond appropriately to variations in wavelengths of light that enable people to see an array of colors. Photoreceptors in the retina are called rods and cones. It is very rare in women.