Chapter 7: Membrane Structure and Function

A collection of flashcards covering key vocabulary terms related to membrane structure and function as presented in the lecture notes.

Phospholipid

A type of lipid molecule that is a major component of cell membranes, having hydrophilic (water-attracting) heads and hydrophobic (water-repelling) tails.

Fluid Mosaic Model

A description of the cell membrane structure where molecules are free to move sideways within a lipid bilayer, creating a mosaic of components.

Diffusion

The process by which molecules move from an area of higher concentration to an area of lower concentration.

Osmosis

The diffusion of water molecules across a selectively permeable membrane.

Active Transport

The movement of substances across a membrane against their concentration gradient, requiring energy, often in the form of ATP.

Exocytosis

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

Endocytosis

The process by which cells internalize substances by engulfing them in a vesicle.

Gated Channels

Channel proteins that open or close in response to specific signals, allowing selective passage of molecules.

Aquaporins

Channel proteins that facilitate the transport of water across the cell membrane.

Selective Permeability

The ability of a cell membrane to allow certain substances to pass while restricting others.

Integral Proteins

Membrane proteins that penetrate the hydrophobic core of the lipid bilayer and can span the entire membrane.

Peripheral Proteins

Membrane proteins that are not embedded in the lipid bilayer but are attached to the membrane's surface.

Cholesterol

A lipid molecule that is a component of animal cell membranes, influencing membrane fluidity depending on temperature.

Glycolipids

Lipids with carbohydrate chains attached, playing a role in cell recognition.

Glycoproteins

Proteins that have carbohydrate groups attached, contributing to cell recognition and signaling.

Electrochemical Gradient

A gradient that combines both concentration and electrical gradients affecting the movement of ions across membranes.