Tag: science & technology

Vitamin D is produced in the skin when exposed to UVB radiation from sunlight, earning it the nickname 'sunshine vitamin'. The body synthesizes this vitamin through a photochemical reaction triggered by sun exposure.

Human somatic (body) cells contain 46 chromosomes total, organized as 23 pairs - one set inherited from each parent. Both '23 pairs' and '46' correctly describe the same fact.

The pharynx is the muscular cavity that connects the mouth and nasal passages to the esophagus (for swallowing food) and larynx (for breathing). It's commonly called the throat.

The average adult human brain weighs approximately 1.4 kg (about 3.1 lbs). Both values represent the same physical weight in different units - 1.4 kg equals roughly 3 pounds.

Proteins are polymers made of amino acid monomers linked by peptide bonds. There are 20 standard amino acids that combine in various sequences to form all the proteins in our body.

An ulcer is an open sore or break in the skin or mucous membrane that fails to heal. Common types include peptic ulcers (stomach/duodenum) and pressure ulcers (bedsores).

Blood plasma is the liquid component of blood in which blood cells (RBCs, WBCs, and platelets) are suspended. It is mostly water and contains proteins, nutrients, hormones, and waste products. Platelets and the various blood cells are the solid components, not the liquid medium.

Hemoglobin is the red pigment in red blood cells that gives blood its characteristic red color. It contains iron and binds oxygen for transport. Plasma is actually pale yellow, platelets are cell fragments, and capillaries are tiny blood vessels - none provide the color.

The heart is the muscular organ that acts as a pump, circulating blood throughout the body via the circulatory system. The brain controls the nervous system, kidneys filter blood, and lungs facilitate gas exchange - none pump blood.