Biology MCQs

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Abscisic Acid plays the most important role in establishing dormancy in seeds. Abscisic Acid has also been found to be present in metazoans, from sponges up to mammals including humans.

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Cardamom (Botanical name: Elettaria cardamomum) is called the Queen of Spices because of its rich aroma and many uses as a medicine and as a flavoring in food and drink.

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As per the WHO definition, within 42 days of the termination of pregnancy, the death of a woman is counted in the Maternal Mortality, irrespective of the duration and site of the pregnancy.

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As cells develop some genes are turned off permanently. All of the cells within a complex multicellular organism such as a human being contain the same DNA; however, the body of such an organism is clearly composed of many different types of cells. What, then, makes a liver cell different from a skin or muscle cell? The answer lies in the way each cell deploys its genome. In other words, the particular combination of genes that are turned on (expressed) or turned off (repressed) dictates cellular morphology (shape) and function. This process of gene expression is regulated by cues from both within and outside cells, and the interplay between these cues and the genome affects essentially all processes that occur during embryonic development and adult life. This means that cells become specialized because the genes that are not required are switched off. Only the genes needed to make a particular type of cell work are switched on. So muscle cells only have the genes needed to make muscle cell proteins switched on. All the other genes, such as those needed to make blood cell proteins and nerve cell proteins, are switched off. But the stem cells are unspecialized and can develop into various tissues.

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Diabetes mellitus occurs when the body does not produce insulin (type I) or when the body does not respond properly to insulin (type II). This results in elevated blood glucose. In either type, overtreatment, or failure to eat properly while on treatment, can lead to hypoglycemia. Most diabetics recognize their symptoms when “low” and know to go eat something before it progresses to a dangerous point. Symptoms of high blood sugar are much different – thirst, increased urination, sleepiness.

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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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Cells of the epidermis produce root hairs near the root apex. These cells are generally thin-walled, in contrast to the cells of the cortex, lying below the surface, which ultimately may become very thick-walled. The root hairs have fundamental importance in absorption of water and nutrients.

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Unlike cows for example don’t have the necessary bacteria in their intestines that make the enzymes necessary to breakdown the 1-4 beta glucose bonds. So we cannot break down cellulose into its constituent glucose molecules as we do with starch.

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Pleiotropism describes the genetic effect of a single gene on multiple phenotypic traits. A classic example of pleiotropy is phenylketonuria, a human disease that affects multiple systems but is caused by one gene defect. The underlying mechanism is that the gene codes for a product that is, for example, used by various cells, or has a signaling function on various targets.

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In the process of photosynthesis, the energy from solar light is converted into the chemical energy.