Short answers, pulled from the story.
Oxygen makes up 65.02 percent of the human body by mass. Carbon accounts for 18.5 percent, while hydrogen comprises 9.5 percent. Nitrogen follows at 3.2 percent, and calcium represents 1.5 percent of total weight.
An average mature human contains roughly 30 trillion cells within their physical frame. This number includes bacteria living inside the body, estimated at 38 trillion organisms. Skin hosts billions of commensal organisms alongside immune cells that protect against invaders.
Digestion begins in the mouth where teeth chew food into smaller pieces. Peristalsis moves chyme through the gastrointestinal tract via muscle contraction. The kidneys filter about 150 quarts of blood daily but produce only one to two liters of urine.
Andreas Vesalius published De humani corporis fabrica in 1543 after pioneering dissection techniques. Galen of Pergamum compiled classical knowledge into texts used throughout the Middle Ages. Matthias Schleiden and Theodor Schwann proposed cell theory in 1838 stating organisms consist of cells.
These five elements form the bulk of every adult male and female structure. Oxygen makes up 65.02 percent of the human body by mass. Carbon accounts for 18.5 percent, while hydrogen comprises 9.5 percent.