Homeostasis and Feedback Mechanisms Vocabulary

Vocabulary practice flashcards covering the basic principles of homeostasis, feedback loops, and physiological effectors.

Homeostasis

The balancing act or mechanism by which the body maintains internal stability through feedback systems.

Negative feedback

The most common mechanism of homeostasis in the body where a variable oscillates right around a set point.

Positive feedback

A feedback mechanism that is rare at the organ system level but does occur at the cellular level.

Control center

The component of a negative feedback system that stores the set point and compares incoming information to it (e.g., a thermostat or the hypothalamus).

Set point

The specific value at which a variable is intended to be maintained, such as $37\,^{\circ}C$ ($98.6\,^{\circ}F$) for human body temperature.

Receptor

Also known as a sensor, this structure monitors and measures a variable and relays information to the control center.

Stimulus

A change in a variable that disturbs homeostasis.

Effector

Structures in the body that respond to signals from the control center to bring about a change and return the system to its set point.

Hypothalamus

The specific control center located in the brain that regulates human body temperature.

Arterioles

Blood vessels that contain smooth muscle which can dilate to bring warm blood to the surface of the skin during overheating.

Sweat glands

Effectors that increase activity to facilitate evaporation and cool the blood when body temperature exceeds the set point.

Skeletal muscle

One of the four specific types of cells in the body that act as effectors in physiology.

Cardiac muscle

One of the four specific types of cells in the body that act as effectors in physiology.

Smooth muscle

One of the four specific types of cells in the body that act as effectors in physiology.

Glands

One of the four specific types of cells in the body that act as effectors in physiology.

Oscillating graph

A visual depiction of negative feedback showing how a variable fluctuates up and down around a normal range or set point.