Tag: science & technology

Sir Alexander Fleming discovered penicillin in 1928 at St. Mary's Hospital, London, when he noticed mold killing bacteria in a petri dish. This accidental revolution in medicine earned him the Nobel Prize. Sir Almroth Wright worked on vaccines, Hopkins discovered vitamins, and Neuberger was a biochemist - none discovered penicillin.

In influenza viruses like H1N1, the H refers to hemagglutinin, a surface glycoprotein that helps the virus bind to host cells. The N refers to neuraminidase. Haemoglobin carries oxygen in blood (not viral). Hongkong is a place. Hemoprotein is a general term for iron-containing proteins, not the specific viral protein.

In H1N1 influenza virus, the 'H' stands for hemagglutinin, which is a surface glycoprotein that helps the virus bind to and enter host cells. The 'N' stands for neuraminidase.

Sir Alexander Fleming discovered penicillin in 1928 at St. Mary's Hospital in London when he noticed that mold (Penicillium notatum) had antibacterial properties against staphylococci.

Normal blood pH is tightly regulated between 7.35 and 7.45, which is slightly alkaline. This narrow range is critical for proper enzyme function and cellular processes. Option A (7.1-7.2) is too acidic and would indicate acidosis. Option D (7) is neutral pH, not physiological pH. Blood must maintain this specific alkaline range for survival.

Normal blood pressure is 120/80 mmHg. High blood pressure (hypertension) is generally defined as 140/90 mmHg or above. Low blood pressure (hypotension) is typically diagnosed through symptoms of inadequate blood flow rather than a fixed number, though values below 90/60 mmHg often indicate hypotension. Option B correctly captures the clinical thresholds.

Blood composition is approximately 55% plasma and 45% blood cells (red blood cells, white blood cells, and platelets). Since plasma is 90% water, and plasma makes up 55% of blood, water constitutes roughly 50% of total blood volume. The 55% figure represents the plasma fraction itself.