Physiological Systems and Homeostasis

These flashcards cover key concepts related to physiological systems, homeostasis, and the endocrine system.

Homeostasis

The stability of the internal environment and the mechanisms used to maintain that stability.

Control Systems

The systems that sense when conditions deviate from ‘normal’ and initiate physiological mechanisms to correct the error.

Negative Feedback

A process that returns the system to its set point by reducing the output or activity.

Positive Feedback

A process that amplifies a response and increases deviation from a set point.

Set Point

A reference point that physiological variables are compared against.

Error Signal

Any difference between the set point and feedback information.

Effectors

Tissues or organs that can alter the internal environment.

Neurosecretory Cells

Excitable cells in the CNS that release hormones into the blood.

Nonneural Endocrine Cells

Cells that are typically stimulated to secrete hormones by other hormones.

Tropic Hormones

Hormones that stimulate other endocrine glands.

HPA Axis

The hypothalamic-pituitary-adrenal axis, a complex network involved in stress response.

Insulin

A hormone produced by the pancreas that helps to lower blood glucose levels.

Glucagon

A hormone produced by the pancreas that helps to raise blood glucose levels.

Homeostatic Challenge

The need to maintain certain physiological variables, like blood glucose levels.

Corticotropin-Releasing Hormone (CRH)

A neurohormone secreted by the hypothalamus that stimulates the release of ACTH.

Adrenocorticotropic Hormone (ACTH)

A tropic hormone released by the anterior pituitary that stimulates the adrenal cortex.

Cortisol

A hormone released by the adrenal cortex that helps to manage stress and metabolism.