IB Sports, exercise and health science A.1.1 Inter-system Communication Key Definitions

The ACL is a key ligament in the knee that stabilizes the joint by preventing excessive forward movement of the tibia relative to the femur.

Receptors that monitor changes in blood pressure.

Receptors that detect changes in the chemical composition of the blood, including oxygen and carbon dioxide levels.

The corpus luteum is a temporary endocrine gland formed in the ovary after ovulation.

A system of glands that release hormones into the bloodstream to regulate various body functions.

Also known as adrenaline, epinephrine is a hormone and neurotransmitter released by the adrenal medulla during the fight-or-flight response.

Erythropoietin (EPO) is a hormone produced by the kidneys that stimulates red blood cell (erythrocyte) production in the bone marrow, improving oxygen delivery to tissues.

Homeostasis is the maintenance of a stable internal environment within an organism, ensuring optimal conditions for cellular processes.

Hormones are chemical messengers secreted by endocrine glands into the bloodstream.

Also known as noradrenaline, norepinephrine is a hormone and neurotransmitter that works alongside epinephrine to regulate the fight-or-flight response.

Osmolarity is the concentration of solutes (such as ions and glucose) in a solution, measured in osmoles per liter (Osm/L). It is crucial for maintaining fluid balance and cell function in the body.

The part of the autonomic nervous system that triggers the "rest and digest" functions.

A peptide is a short chain of amino acids linked by peptide bonds.

pH is a measure of hydrogen ion (H⁺) concentration, determining how acidic or basic a solution is.

Specialized receptors that detect changes in body position and movement.

A steroid is a type of lipid molecule derived from cholesterol.

The part of the autonomic nervous system that triggers the body's "fight or flight" responses.

Tachycardia refers to an abnormally high heart rate, typically above 100 beats per minute (bpm) in adults.

The narrowing of blood vessels, directing blood to vital organs during stress or physical exertion.

The widening of blood vessels, allowing more blood flow to active tissues, like muscles during exercise.

Ventilation is the process of moving air or water across the gas-exchange surface to refresh the supply of gases and maintain the concentration gradient.