Biology MCQs

Notes:
Hemoglobin in humans has a very high affinity for carbon monoxide, forming carboxyhemoglobin which is a very bright red in color. Carbon monoxide is thus problematic for humans because it has affinity higher than that of oxygen.

Notes:
When the body’s immune system cells destroy the insulin producing beta cells of the pancreas is termed as Type 1 diabetes. Symptoms may include increased thirst, frequent urination, hunger, fatigue and blurred vision.

Notes:
A cornea transplant also called as keratoplasty is a surgical procedure to replace part of your cornea with corneal tissue from a donor. Cornea does not link up with blood vessels, this makes the Cornea Transplantation easy and used more widely.

Notes:
Viruses are small infectious agents that can replicate only inside the living cells of an organism. Viruses are classified based on the type of genetic material they contain. Some viruses have DNA as their genetic material, while others have RNA. Some viruses have both DNA and RNA as their genetic material.

DNA viruses have double-stranded DNA as their genetic material. They replicate their DNA using the enzymes and machinery of the host cell. Examples of DNA viruses include herpes viruses, pox viruses, and adenoviruses.

RNA viruses have single-stranded RNA as their genetic material. They replicate their RNA using the enzymes and machinery of the host cell. Examples of RNA viruses include influenza viruses, HIV, and coronaviruses.

Viruses that have both DNA and RNA as their genetic material are known as “retroviruses.” These viruses contain a single strand of RNA, but they use an enzyme called reverse transcriptase to convert their RNA into DNA. The DNA is then integrated into the host cell’s genome and replicated along with the host cell’s DNA. Examples of retroviruses include HIV and the human T-cell leukemia virus.

Notes:
Bt cotton is an insect-resistant transgenic crop designed to combat the bullworm. Bt is a soil bacterium containing Cry genes that encode crystal proteins which are fatal to some Lepidopteran caterpillars when ingested.

Notes:
Apart from air, 15 of the essential nutrients are supplied by the soil to plants. Out of them, Nitrogen, Phosphorus and Potassium are called primary nutrients or macronutrients. Three more elements viz. Calcium, Magnesium and Sulphur are known as secondary nutrients because the deficiency of them is less likely to be a growth limiting factor. 

Notes:
Blood is carried through the body by Blood Vessels. With the help of perfusion process capillaries supplies blood to the tissues. The diameter of capillary ranges from 5-10 micrometers. The diameter of arteriole is approximately 30 micrometer.

Notes:
Natural Pearls are formed when an irritant usually a parasite works its way into an oyster, mussel, or clam. As a defense mechanism, a fluid is used to coat the irritant. Layer upon layer of this coating, called nacre, is deposited until a lustrous pearl is formed.

Notes:
Plant cells have a cell wall, chloroplasts and other specialized plastids, and a large central vacuole, which are not found within animal cells.

Notes:
An autopsy is a surgical procedure that consists of a thorough examination of a corpse by dissection to determine the cause, mode and manner of death or to evaluate any disease or injury that may be present for research or educational purposes.