Homeostasis and Cell Transport Review

These flashcards cover key concepts related to homeostasis, cell membrane structure and function, types of transport, and solution dynamics to assist in exam preparation.

Homeostasis

The need of an organism to stay stable by regulating internal conditions.

Positive Feedback Mechanism

A process where the output of a system intensifies the response, e.g., childbirth.

Negative Feedback Mechanism

A process where the output of a system causes a counter response to return to a set point, e.g., regulation of body temperature.

Cell Membrane

A structure composed of a phospholipid bilayer that is selectively permeable, allowing certain materials to pass.

Passive Transport

Movement of molecules from an area of high concentration to an area of low concentration without requiring energy.

Active Transport

Movement of molecules against the concentration gradient from an area of low concentration to an area of high concentration, requiring energy.

Simple Diffusion

The spreading out of molecules across a membrane until equilibrium is reached, moving down the gradient.

Facilitated Diffusion

Diffusion of molecules that require assistance from a transport protein to pass through the membrane.

Osmosis

The simple diffusion of water across the cell membrane, moving down the concentration gradient.

Solute

The substance that is dissolved in a solution, e.g., lemonade powder in lemonade.

Solvent

The substance in which the solute is dissolved, e.g., water in lemonade.

Concentration (in terms of a solution)

The amount of solute dissolved in the solvent.

Hypertonic Environment

A cell environment where the concentration of solute outside the cell is greater than inside, causing the cell to shrink.

Hypotonic Environment

A cell environment where the concentration of solute outside the cell is less than inside, causing the cell to swell.

Isotonic Environment

A cell environment where the concentration of solute is equal inside and outside the cell, resulting in no net movement.