IB Biology Topic D3.3: Homeostasis Key Definitions

Aquaporins are specialized proteins that facilitate water movement across cell membranes.

Excretion is the removal of metabolic waste products.

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

A solution with a higher solute concentration compared to another solution.

The loop of Henle is a U-shaped tube found in the nephron, the kidney’s functional unit. It is responsible for creating a concentration gradient in the medulla, enabling the production of concentrated urine.

A negative feedback loop is a self-regulating system that detects changes in a variable and triggers responses to bring it back to a set point.

Osmoregulation is the process of maintaining the balance of water and solutes in the body.

Osmosis is the passive movement of water molecules across a semi-permeable membrane from a region of lower solute concentration (hypotonic) to a region of higher solute concentration (hypertonic).

pH is a measure of how acidic or basic a solution is, ranging from 0 (very acidic) to 14 (very basic).

The liquid component of blood, consisting mostly of water, proteins, and other substances.

A set point is the ideal value for a specific variable that the body strives to maintain.

Thermoregulation is the process by which organisms maintain their core body temperature within a narrow range, typically around 37°C in humans.