NEET Practice Questions (MCQs) with Answers & Solutions

Biofertilizers are substances containing living microorganisms which, when applied to seeds, plant surfaces, or soil, colonize the rhizosphere or the interior of the plant and promote growth by increasing the supply or availability of primary nutrients to the host plant. Organisms such as Glomus (a mycorrhizal fungi), Cyanobacteria, and Azospirillum are all known to be beneficial in forming biofertilizers. Hence, the correct answer is 'All the given'.

Ensilage or silage is a type of fodder made from green foliage crops which have been preserved by fermentation to the point of acidification. This process is called ensiling. Carbohydrates play a crucial role in this process as they are fermented by bacteria to produce lactic acid, which acts as a preservative. Thus, carbohydrates are essential for preparing silage.

The fungus Saccharomyces cerevisiae, also known as baker's yeast, is commonly used in baking bread. This yeast ferments the sugars in the dough, producing carbon dioxide and ethanol, which cause the dough to rise and give bread its texture.

Clostridium butyricum is a bacterium that is known for producing short-chain fatty acids such as butyric acid. These fatty acids are important in various biochemical processes and have been studied for their potential health benefits.

Mycorrhiza refers to a symbiotic association between a fungus and the roots of a vascular plant. This relationship is mutually beneficial: the fungus aids in the absorption of water and nutrients for the plant, while the plant supplies carbohydrates and other organic compounds to the fungus.

Streptokinase is an enzyme used to dissolve blood clots in blood vessels. It is often used in the treatment of myocardial infarction (heart attack) and other conditions caused by blood clots. Streptokinase works by converting plasminogen to plasmin, which then breaks down fibrin clots.

Cyclosporin-A is an immunosuppressive drug widely used in organ transplantation to prevent rejection. It works by inhibiting the activation of T-cells, which are responsible for attacking the transplanted organ. This helps to reduce the immune response and increase the chances of transplant success.

Heterotrophs are bacteria that play a crucial role in the purification of sewage. They break down organic matter present in sewage through the process of decomposition, thereby reducing pollution and helping in the treatment of wastewater.