Homeostasis and Membrane Transport

These flashcards cover crucial concepts and terminology related to homeostasis, membrane transport, and their physiological significance.

Homeostasis

The ability of the body to maintain a relatively stable internal environment despite external variances.

Negative Feedback

A control mechanism in which a change in a physiological variable triggers a response that counteracts the initial change.

Positive Feedback

A control mechanism that amplifies or increases an effect or output.

Set Point

The predetermined normal value of a physiological variable that the body attempts to maintain.

Osmosis

The movement of water across a semi-permeable membrane, driven by a concentration gradient of solutes.

Osmolarity

The number of osmotically active particles per volume of water (e.g., mOsmoles/L).

Tonicity

The pressure caused by osmotic gradient across a cell membrane, which determines changes in cell volume.

Intracellular Fluid (ICF)

Fluid located inside cells, containing a different composition and concentration of ions compared to extracellular fluid.

Extracellular Fluid (ECF)

Fluid found outside cells, including blood plasma and interstitial fluid.

Feed-Forward Control

A mechanism in which the body anticipates a change in a variable before it happens and prepares for it.

Diffusion

The movement of solutes from an area of higher concentration to an area of lower concentration.

Primary Active Transport

Transport that requires energy to move solutes against their concentration gradient, such as the Na+/K+ pump.

Secondary Active Transport

Transport that utilizes the concentration gradient created by primary active transport to move other solutes.