Homeostasis and Appetite Regulation

A collection of key vocabulary terms related to homeostasis, appetite regulation, and the challenges of obesity and eating disorders.

homeostasis

The maintenance of a relatively constant internal physiological environment.

motivation

The psychological process that induces or sustains a particular behavior.

thermoregulation

The active process of maintaining a relatively constant internal temperature through behavioral and physiological adjustments.

endotherm

An animal whose body temperature is regulated chiefly by internal metabolic processes.

ectotherm

An animal whose body temperature is regulated by, and whose heat comes mainly from, the environment.

negative feedback

The process whereby a system monitors its own output and reduces its activity when a set point is reached.

set point

The point of reference in a feedback system.

set zone

The optimal range of a variable that a negative feedback system tries to maintain.

allostasis

The varying behavioral and physiological adjustments that an individual makes in order to maintain optimal functioning of a regulated system in the face of changing environmental stressors.

osmotic thirst

A desire to ingest fluids that is stimulated by high concentration of solute (like salt) in the extracellular compartment.

hypovolemic thirst

A desire to ingest fluids that is stimulated by a reduction in volume of the extracellular fluid.

vasopressin

A peptide hormone from the posterior pituitary that promotes water conservation and increases blood pressure.

aldosterone

A mineralocorticoid hormone, secreted by the adrenal cortex, that promotes the conservation of sodium by the kidneys.

appetite

The desire for food, regulated by various hormonal signals and neural circuits.

leptin

A peptide hormone released by fat cells that helps to regulate energy balance by inhibiting hunger.

ghrelin

A peptide gut hormone that increases hunger and is released by the stomach.

PYY3-36

A peptide gut hormone believed to act on the hypothalamic appetite system to suppress appetite.

metabolic adaptation

The process by which the body adjusts its metabolic rate in response to changes in energy intake or expenditure.

BMI

Body Mass Index, a measure that uses height and weight to categorize individuals into weight classifications like underweight, normal weight, overweight, and obesity.

anorexia nervosa

A syndrome in which individuals severely deprive themselves of food.

bulimia nervosa

A syndrome in which individuals periodically gorge themselves with food and then engage in compensatory behaviors like vomiting.

binge eating disorder

A psychiatric diagnosis characterized by spontaneously gorging on food to the point of illness.