Biology MCQs

Notes:
Cork is a prime-subset of bark tissue that is harvested for commercial use primarily from Quercus suber. It is endemic to the Mediterranean region. Cork is composed of suberin, a hydrophobic substance and, because of its impermeable, buoyant, elastic, and fire retardant properties, it is used in a variety of products, such as wine stoppers.

Notes:
Cloves are the aromatic dried flower buds of a tree in the family Myrtaceae. The clove tree is an evergreen that grows to a height ranging from 8–12 m, having large leaves and sanguine flowers in numerous groups of terminal clusters. The flower buds are at first of a pale colour and gradually become green, after which they develop into a bright red, when they are harvested by farmer.

Notes:
The monosaccharides responsible for sweet taste in fruits is Fructose. Fructose is a natural form of sugar, which is why fruits with large amounts of fructose taste sweet. Fructose is an element that causes fruits to sweet in taste is a type of sugar which already present in the human body with glucose.

Notes:
Chlorophyll, a photo-receptive pigment, allows plants to absorb sunlight. Chlorophyll is a chlorine pigment, which is structurally similar to and produced through the same metabolic pathway as other porphyrin pigments such as heme. At the center of the chlorine ring is a magnesium ion. The molecular formula of C55H70O6N4 Mg. Hence, chlorophyll as a pigment lacks calcium.

Notes:
Oxygen liberated during photosynthesis comes from the splitting or hydrolysis of water in the green plants. Cornelius van Niel experimentally proved for the first time that the oxygen liberated during photosynthesis comes from water and not from carbon dioxide. Oxygen is expelled out of plants and Hydrogen is used to reduce Carbon dioxide to produce carbohydrates.

Notes:
The activity of enzymes, which are generally globular proteins, is determined by their three-dimensional structure. This structure allows them to bind to a substrate and catalyze their involvement in a reaction. Enzymes vary in size, ranging from 62 amino acid residues for the monomer of 4-oxalocrotonate tautomerase, to over 2,500 residues in animal fatty acid synthase. Their specific ability to bind to substrates enables reactions to occur in the body, playing a crucial role in metabolism.

Notes:
A neuron is a cell that carries electrical impulses. Neurons are the basic units of the brain and nervous system. They are responsible for receiving sensory input from the external world, for sending motor commands to our muscles, and for transforming and relaying the electrical signals at every step in between.

Notes:
Pneumatophores are spongy erect roots extending above the surface of the water that facilitate the exchange of oxygen and carbon dioxide for the roots. They are specialized root structures that grow out from the water surface where inadequate oxygen required for normal respiration of the roots is present. They are seen in many mangrove species.

Notes:
Bt Brinjal is a genetically modified (GM) crop created by inserting Cry 1Ac gene from the soil bacterium Bacillus thuringiensis into Brinjal. The insertion of the gene gives Brinjal plant resistance against lepidopteron pets/insects like the Brinjal Fruit and Shoot Borer (Leucinodes orbonalis) and Fruit Borer (Helicoverpa armigera).

Notes:
Glycogen is a multi-branched polysaccharide of glucose that serves as a form of energy storage in humans, animals, and fungi. The polysaccharide structure represents the main storage form of glucose in the body. Glycogen is the analogue of starch, a glucose polymer that functions as energy storage in plants.