Lecture 4 (Homeostasis and Thermoregulation)

Homeostasis

The ability of an organism to maintain stable internal conditions.

Negative feedback

A process that reverses a change to keep conditions stable.

Positive feedback

A process that increases a change until a specific event is completed.

Conformer

An organism that changes its internal conditions to match the environment.

Regulator

An organism that uses energy to maintain stable internal conditions.

Endotherm

An animal that generates heat internally to regulate body temperature.

Ectotherm

An animal that relies on external sources for body heat.

Circadian rhythm

A biological cycle that repeats about every 24 hours.

Thermoregulation

The process of maintaining a stable internal body temperature.

Radiation

Heat transfer through electromagnetic waves (no contact needed).

Evaporation

Heat loss when liquid changes to gas (like sweating).

Convection

Heat transfer through movement of air or water.

Conduction

Heat transfer through direct contact.

Countercurrent exchange

A system where fluids flow in opposite directions to maximize heat or gas exchange.

Thermogenesis

Heat production by metabolic processes.

Metabolism

All chemical reactions in an organism that maintain life