Passive Propagation of Membrane Potential

Flashcards covering key concepts of cell theory, membrane structure, transport mechanisms, and types of cellular interactions.

Cell Theory

The principle that the cell is the basic structural and functional unit of life.

Plasma Membrane

A selective barrier that separates the cell interior from the external environment.

Fluid Mosaic Model

The model describing the structure of the plasma membrane as a mosaic of various proteins embedded in a fluid phospholipid bilayer.

Integral Proteins

Proteins that penetrate the hydrophobic core of the lipid bilayer, often functioning as transport channels.

Peripheral Proteins

Proteins that are bound to the surface of the membrane, often involved in signaling or structural roles.

Membrane Potential

The voltage difference across a cell membrane, essential for various cellular processes.

Passive Transport

The movement of substances across a cell membrane without the use of energy (e.g., diffusion, osmosis).

Active Transport

The movement of substances against their concentration gradient, requiring energy, usually in the form of ATP.

Facilitated Diffusion

The process by which large polar molecules cross the lipid bilayer with the help of integral proteins.

Osmosis

The diffusion of water across a semipermeable membrane from a region of low solute concentration to high solute concentration.

Endocytosis

The process by which cells internalize substances from the external environment by engulfing them.

Exocytosis

The process of vesicles fusing with the plasma membrane to release their contents outside the cell.

Tonicity

The ability of a solution to cause a cell to gain or lose water, based on solute concentration.

Filtration

The movement of water and solutes through a membrane by a pressure gradient.

Symport System

An active transport mechanism that moves two substances in the same direction across a membrane.

Antiport System

An active transport mechanism that moves two substances in opposite directions across a membrane.