Biology MCQs

Notes:
Seedling root dip, Seed, and Soil Treatment are the important applications of biofertilizers.

Notes:
Saprophytes are the organisms which depend for food on dead and decaying material. They secrete digestive substances into the surrounding environment and break down the organic matter into simpler substances. The nutrients thus produced are absorbed directly through the cell membranes of the organisms.

Notes:
Blubber is a thick layer of vascularized adipose tissue found under the skin particularly whales inhabiting of Arctic ocean. It’s presence insulate their body from ice cold. The energy stored in blubber includes both proteins (mostly collagen) and fats (mostly lipids). Blubber covers the entire body of animals such as seals, whales, and walruses—except for their fins, flippers, and flukes. Whaling largely targeted the collection of blubber: whalers rendered it into oil in try pots, or later, in vats on factory ships. The oil could serve in the manufacture of soap, leather, and cosmetics. Whale oil was used in candles as wax, and in oil lamps as fuel.

Notes:
Females have single uterus. Also known as womb, it is a major female hormone-responsive reproductive sex organ of humans and most other mammals. It is within the uterus that the fetus develops during gestation.

Notes:
Penicillin the so called ‘Wonder drug’ discovered by Alexander Fleming in 1927 is produced from the genus of fungi “Penicillia”. All penicillin are â-lactam antibiotics and are used in the treatment of bacterial infections caused by susceptible, usually Grampositive organisms.

Notes:
The red blood cells develop in the bone marrow and circulate for about 100–120 days in the body before their components are recycled by macrophages in liver and spleen (Grave yard of RBC). The old, worn out and dead RBC are destroyed mainly in an organ called spleen.

Notes:
Ascariasis is a disease caused by the parasitic roundworm Ascaris lumbricoides. Infection occurs by eating food or drink contaminated with Ascaris eggs from feces. Ascariasis is most common in places without modern sanitation.

Notes:
Wolffia is a genus of 9 to 11 species which include the smallest flowering plants on Earth. Commonly called water-meal or duckweed, these aquatic plants resemble specks of cornmeal floating on the water. Wolffia species are free-floating thalli, green or yellow-green, and without roots. The flower is produced in a depression on the top surface of the plant body. It has one stamen and one pistil.

Notes:
Hereditary characteristics are passed on from parent to the offspring chiefly through genes. Genes are the working subunits of Deoxyribonucleic acid (DNA), the chemical information database that carries the complete set of instructions for the cell as to the nature of the proteins produced by it, its life span, maturity, function and death. The transmission of genes to an organism’s offspring is the basis of the inheritance of phenotypic traits.

Notes:
The islets of Langerhans are the regions of the pancreas that contain cells that produce hormones. There are five types of cells in the islets of Langerhans: beta cells secrete insulin; alpha cells secrete glucagon; PP cells secrete pancreatic polypeptide; delta cells secrete somatostatin; and epsilon cells secrete ghrelin.