Homeostasis & Thermoregulation Flashcards

Flashcards on Homeostasis and Thermoregulation in Animals

Homeostasis

The capacity of animals to adjust to the environment over the short term by physiological responses and maintain a favorable internal environment.

Plasma Membranes

Animal must be arranged so that all of its living cells are bathed in an aqueous medium because plasma membranes need to maintain their fluid integrity.

Interstitial Fluid

Fills the spaces between cells and provides cells with a controllable internal environment in larger, more complex animals.

Regulator

An animal that moderates internal change in the face of environmental fluctuations (e.g., freshwater fish).

Conformer

An animal that allows its internal condition to vary with environmental fluctuations (e.g., marine invertebrates).

Negative Feedback

A change in a variable triggers control mechanisms to counteract further change in the same direction; most homeostatic mechanisms in animals use this.

Positive Feedback

A change in a variable triggers mechanisms that amplify rather than reverse the change (e.g., birthing process).

Thermoregulation

The process of maintaining body temperature within a range conducive to metabolism.

Ectotherm

An animal that warms its body mainly by absorbing heat from its surroundings.

Endotherm

An animal that derives most of its body heat from its own metabolism.

Conduction

Direct transfer of heat between the environment and a body surface.

Convection

Transfer of heat by movement of air or liquid past a body surface.

Radiation

Emission of electromagnetic radiation.

Evaporation

Loss of heat by liquid changing to gas.

Acclimatization

Adjustments to a new range of temperatures over a period of days or weeks.

Torpor

A physiological state in which activity is low and metabolism decreases.

Hibernation

Long-term torpor due to cold and decreased food availability, characterized by decreased body temperature and metabolic rate.

Estivation

"Summer hibernation" to survive periods of extreme heat and water shortage.

Daily Torpor

Cyclic decreases in body temperature and metabolism.