Homeostasis and Feedback Control AG 22nd

Vocabulary flashcards covering concepts of homeostasis, reflex pathways, feedback types, thermoregulation, nervous and endocrine control, and hormone regulation.

Homeostasis

Maintenance of stable internal conditions in the body through regulatory feedback mechanisms.

Feedback control

Regulatory system that maintains a variable around a set point by sensing deviations and adjusting effectors.

Reflex arc

A neural pathway consisting of a sensor, integrating center, and effector that mediates a reflex.

Sensor

Receptor sensitive to a particular variable that detects change.

Integrating center

Control center (often in the brain) that processes sensory input and determines the response.

Effector

Organ or cell that executes the response to counteract a deviation from the set point.

Negative feedback loop

A regulatory loop in which the response counteracts the initial change to restore the variable toward the set point.

Positive feedback loop

A regulatory loop in which the end product amplifies the initial change, accelerating the process.

Thermoregulation

Maintenance of core body temperature using sensors, a central regulatory center, and effectors (e.g., sweating, shivering).

Thermoregulatory center

Brain region that monitors temperature and coordinates responses to maintain core temperature.

Antagonistic effectors

Opposing effectors that move conditions in opposite directions to keep physiology within a normal range (e.g., sweating vs. shivering).

Nervous system

System that innervates organs with nerve fibers to coordinate rapid responses.

Endocrine system

System that releases hormones into the blood, transporting them to multiple target organs.

Insulin

Hormone produced by pancreatic islets that lowers blood glucose by promoting cellular uptake.

Glucagon

Hormone produced by pancreatic islets that raises blood glucose by promoting glucose release from the liver.

Pancreatic islets (Islets of Langerhans)

Endocrine tissue in the pancreas that secretes insulin and glucagon.

Blood glucose

Concentration of glucose in the blood, tightly regulated by insulin and glucagon.

Dynamic constancy

Maintenance of a normal range for physiological variables through opposing effectors.