Cellular Transport Mechanisms

Flashcards covering key vocabulary terms related to cellular transport mechanisms, including diffusion, osmosis, and membrane permeability, from the lecture notes.

Transfer mechanisms

Processes that control what substances enter and exit the cell.

Plasma membrane

The cellular structure that separates the inside of the cell from the outside and is responsible for regulating transport.

Selectively permeable

A property of the plasma membrane that means it allows certain materials to pass through while blocking others, maintaining a controlled internal environment.

Simple diffusion

The natural movement of molecules from an area of high concentration toward an area of low concentration.

Brownian motion

Random movement of molecules resulting in collisions with each other.

Spontaneous

Referring to processes like simple diffusion that happen by themselves without requiring energy expenditure.

Concentration gradient

The difference in concentration between two areas.

Down the concentration gradient

Movement from an area of high concentration to an area of low concentration.

Permeability of the membrane

How easily a substance can pass through a membrane.

Facilitated diffusion

A type of passive transfer where molecules move down their concentration gradient with the help of transporters or carriers, without the cell spending ATP.

Insulin

A hormone involved in sugar metabolism that regulates the number of glucose transporters on the plasma membrane.

Osmosis

The movement of water molecules (solvent) through a selectively permeable membrane from a low solute concentration solution (high water) to a high solute concentration solution (low water).

Isotonic solution

A solution with a solute concentration equal to that inside the cell, resulting in no net water movement.

Hypotonic solution

A solution with a lower solute concentration (higher water content) than inside the cell, causing water to move into the cell and it to swell.

Hypertonic solution

A solution with a higher solute concentration (lower water content) than inside the cell, causing water to move out of the cell and it to shrink.

Dialysis

The movement of solutes through a selectively permeable membrane; often refers to the process of filtering waste products from blood when kidneys fail.

Blood dialysis

A medical procedure using a machine with a selectively permeable membrane to remove waste products like urea and uric acid from a patient's blood.

Toxins

Substances that can interfere with essential cellular functions, such as paralyzing ion pumps, which can lead to cell death.