Body systems

The wave on an electrocardiogram that shows the heart's lower chambers recovering electrically after each beat.

A heart rate faster than normal; in an adult, more than 100 beats per minute.

A breathing rate faster than normal, above 20 breaths per minute in an adult.

A movement disorder with repeated movements a person cannot control, most often of the face, lips and tongue.

A cell that carries the receptor for a particular hormone, so the hormone can act on it; also a red blood cell shaped like a target.

The firm plate of dense fibrous tissue inside each eyelid that gives the lid its shape and holds its oil glands.

An inherited disease in which a missing enzyme lets a fatty substance build up and destroy nerve cells in the brain and spinal cord.

Total body surface area: the whole skin surface of the body, used to describe how much of it a burn covers.

Continuous heart rhythm monitoring in which a small device worn by the client sends the ECG signal to a central screen.

The part of each side of the brain, above the ear, that handles hearing, memory and understanding language.

The fan-shaped chewing muscle over the side of the head, running from the skull at the temple to the mandible, that closes the jaw.

The joint in front of each ear where the lower jaw meets the temporal bone, which lets the mouth open and close.

A tough cord of tissue that attaches a muscle to a bone.

The three long, narrow bands of smooth muscle along the outside of the colon, formed by its outer longitudinal muscle layer.

A collapsed lung in which air keeps building up in the chest under pressure and presses on the heart and the other lung.

Anything a pregnant person is exposed to that can cause birth defects in the developing baby.

One of the two male glands in the scrotum that make sperm and the hormone testosterone; plural testes.

The main male sex hormone, made mostly in the testes and in small amounts by the ovaries and adrenal glands.

A serious illness caused by a nerve toxin made by the bacterium Clostridium tetani.

Involuntary muscle cramps and spasms that come from nerves firing too easily.

A congenital heart defect made up of four problems in the structure of the heart.

A pair of egg-shaped masses deep in the brain that relay sensory signals to the cerebral cortex.

An inherited blood disorder in which the body makes too little normal hemoglobin.

The body's control of its own temperature, keeping it within a narrow normal range.

The part of the leg between the hip and the knee.

The last part of pregnancy, from week 28 until birth.

Relating to the chest, or to the middle part of the spine.

The body's largest lymph vessel, which carries lymph from the lower body and the left upper body into the left subclavian vein.

The chest: the part of the body between the neck and the abdomen.

A buzzing or vibrating feeling felt with the fingertips over a blood vessel or the heart.

An enzyme in the blood that turns fibrinogen into fibrin, the threads that hold a blood clot together.

A blood platelet count below normal, under 150,000/mm3.

A blockage of a blood vessel by a blood clot that formed in one place and traveled through the blood to another.

Inflammation of a vein with a clot in it, most often a superficial vein of the leg.

The forming of a blood clot (a thrombus) inside a blood vessel or the heart.

A tumor that grows from the epithelial cells of the thymus; the most common tumor of the anterior mediastinum.

One of a group of hormones made by the thymus that help T lymphocytes develop and mature.

A small gland in the upper chest, behind the breastbone, where T cells (a kind of white blood cell) mature.

Relating to the thyroid gland in the neck or the hormones it makes; often used alone to mean the gland itself.

The largest cartilage of the larynx, a shield that forms its front wall; its ridge is the Adam's apple.

A butterfly-shaped gland at the front of the neck that makes hormones that control the body's metabolism.

A hormone made by the thyroid gland that controls how fast the body uses energy.

A sudden, life-threatening flare of hyperthyroidism, with high fever, a very fast heart rate, agitation and confusion.

Surgery to remove all or part of the thyroid gland in the neck.

The main hormone of the thyroid gland, which carries four iodine atoms; written T4.

The large inner bone of the lower leg, between the knee and the ankle; the shinbone.

The amount of air moved in or out of the lungs with one normal breath.

A fungal infection of the skin, hair or nails.

A fungal infection of the scalp and hair, also called ringworm of the scalp.

A fungal infection of the skin of the body, commonly called ringworm, although no worm is involved.