Biology MCQs

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Animal cells do not have cell walls. Cell walls are found in plant cells. Other given organelles like Mitochondria, Ribosome and Cytoplasm are present in animal cells.

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Opium is dried latex which is obtained from the seed capsules of the opium poppy Papaver somniferum.

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Auxins are a class of plant hormones with some morphogen-like characteristics. Auxin is basically a Weak Organic Acid and It is produced in the stem tip that promotes the elongation in the cells.

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The corpus callosum is a large, C-shaped nerve fiber bundle which is found beneath the cerebral cortex. It stretches across the midline of the brain. IT connects the left and right cerebral hemispheres.

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The Bovine spongiform encephalopathy (BSE) is commonly known as Mad Cow Disease. It is a brain disorder in an adult cattle that may be spread to humans through diseased meat.

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The primary reason why fruits ripen quicken when stored in a rice container is due to ethylene accumulation. Differences in the rate of ripening between fruits kept in a rice container and a wheat container might be due to the differences in carbon dioxide emission and self heating nature of these grains. Both wheat and rice grains (esp. brown rice) when not completely milled, still actively respire, thus releasing carbon dioxide and energy. Carbon dioxide is a known inducer of ethylene biosynthesis in a number of fruits e.g. tomato. Rice grains without a husk typically have no dormancy and thus respire more at normal storage conditions. Most wheat grains have moderate to high dormancy periods and respire less at normal storage conditions. This is the reason why fruits stored in a rice container ripen faster than the ones stored in a wheat container

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The primary function of the small intestine is the absorption of nutrients and minerals from food. The small intestine has three distinct regions the duodenum, jejunum and ileum. The duodenum receives bile and pancreatic juice through the pancreatic duct. The jejunum is the midsection of the small intestine, connecting the duodenum to the ileum.

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Bacterium contain no membrane bound nucleus and rarely contain membrane bound organelles. Simply, most don’t have any large organelles with their own membranes; this means no nucleus, no mitochondria and no chloroplast. Even if a bacteria wanted to have mitochondria , it is couldn’t.

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Subsidiary cells are the accessory cells to guard cells in the epidermis of plants. Two or four subsidiary cells are found surrounding the pair of guard cells. Subsidiary cells do not consist of chloroplasts. They provide support for the functioning of guard cells in the epidermis.

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White blood cells help you fight infection.  When one gets sick, white blood cell count is higher than normal. This is because your body is releasing more of these cells to fight the infection.