Anatomy and Physiology Terms

Pressure is never a fixed number, moving through the day with activity, sleep, posture and stress, which is why single readings mislead.

Wall thickness tracks the pressure a vessel must contain, which is why an artery and a vein of equal width behave nothing alike.

A seal built into the brain's blood vessels that keeps most of what circulates in the blood from reaching brain tissue.

Nearly all nutrition is taken up in the first section, while the second exists largely to reclaim water before waste is passed.

Everything the arm can do or feel passes through one braided tangle behind the collarbone, which is why damage there spreads so widely.

The brain stem connects the brain to the spinal cord and controls fundamental automatic functions including breathing, heart rate, and consciousness.

A gland that reorganizes itself repeatedly across a lifetime, which is why what counts as normal in it keeps changing.

One root with two destinations: nearly always the heart, but occasionally the stomach opening that happens to lie beside it.

Pump and pipework are described as a single system because trouble in either one changes what reaches the tissues at the far end.

The fork in the airway, and the reason an inhaled object almost always ends up in the right lung rather than the left.

Narrowing here is one of the more treatable roads to stroke, which is why neck vessels are imaged after brief neurological symptoms.

No blood supply and no nerves: cartilage neither heals well nor hurts directly, so joint pain comes from the structures around it.

Anatomy and dentistry use one word for opposite things: a normal hollow space, and a hole that has no business being there.

Wide, blind-ended and full of liquid contents, it hides trouble for longer than the narrow left side of the colon does.

Everything a body does happens inside one of these compartments, which is why disease is ultimately described at this scale.

The controlled release of energy from food inside a cell, captured as ATP rather than lost all at once as heat.

Two opposite streams of chemistry running at once inside every cell, one tearing molecules down and one building them up.

Damage on one side shows on the same side of the body, the opposite of what the rest of the brain does.

One half of the cerebrum, the part of the brain that controls muscle functions and also controls speech, thought, emotions, reading, writing, and learning.

Each half controls the opposite side of the body, so the site of an injury predicts which side loses function.