2B notes (homeostasis)

Flashcards covering the roles of major components in response pathways, the concept of homeostasis and feedback mechanisms, definitions of hormonal signaling components, and the relationship between homeostatic disruption and disease.

Stimulus

A detectable change that initiates a response pathway.

Receptor

A component in a response pathway that detects a stimulus.

Control Center

A component in a response pathway that integrates information from the receptor and sends instructions.

Effector

A component in a response pathway that causes a response based on instructions from the control center.

Response

The body's reaction caused by the effector.

Homeostasis

The process of maintaining a stable internal environment where internal variables fluctuate around a set point.

Set Point

The ideal value or narrow range around which internal variables are maintained during homeostasis.

Negative Feedback

A feedback mechanism that reduces the original stimulus to maintain balance and keep internal variables near a set point.

Positive Feedback

A feedback mechanism that amplifies the original stimulus, pushing the variable further from the set point until an endpoint is reached.

Hormone

An endocrine signal that travels long distances via the blood to target cells.

Endocrine Gland

A gland that secretes hormones into the bloodstream.

Endocrine Tissue

Tissue that secretes hormones.

Target Cell

A cell that possesses specific receptors for a particular hormone or signaling molecule, allowing it to respond to that signal.

Physiological Dysregulation

A condition that occurs when homeostatic feedback loops fail, leading to an inability to maintain stable internal conditions, often resulting in disease.

Paracrine Signals

Signals that act on nearby cells.

Autocrine Signals

Signals that act on the same cell that secreted them.

Cytokines

Hormone-like signals that are secreted by immune cells.