Cell Membrane Structure and Function

Flashcards covering key vocabulary and concepts related to cell membrane structure and function.

Endoplasmic Reticulum

An organelle involved in the synthesis and transport of proteins and lipids.

Phospholipid Bilayer

A double layer of phospholipids that makes up the cell membrane, with hydrophilic heads facing outward and hydrophobic tails facing inward.

Amphipathic

Describing a molecule that has both hydrophobic and hydrophilic parts.

Fluid Mosaic Model

A model describing the cell membrane as a mosaic of diverse protein molecules floating in or on the fluid lipid bilayer.

Cholesterol

A sterol that can influence the fluidity and stability of the cell membrane.

Transmembrane Proteins

Proteins that span the entire thickness of the membrane and serve various functions such as transport.

Lateral Diffusion

The movement of membrane proteins and lipids within the same layer of the membrane.

Flip-Flop

The rare movement of phospholipids from one leaflet of the bilayer to the other.

Hydrophilic

Having an affinity for water; typically polar or charged molecules.

Hydrophobic

Repelling water; typically nonpolar molecules.

Transport Vesicle

Membrane-bound compartments that transport materials within the cell and to the membrane.

Peripheral Membrane Proteins

Proteins that are loosely attached to the membrane and can be easily removed.

Cytoskeleton

A network of fibers that provides structural support and shape to a cell.

FRAP

Fluorescence Recovery After Photobleaching, a technique used to measure the movement of membrane proteins.

Polarized Membrane Proteins

Membrane proteins that have distinct distributions and functions in different regions of the cell membrane.

Membrane Fluidity

The viscosity of the lipid bilayer of a cell membrane, which is affected by temperature, fatty acid composition, and cholesterol.

Vesicle

A small membrane-bound sac that transports substances in a cell.

Glycoprotein

A protein with carbohydrate chains attached that extend into the extracellular environment.

Lumen

The inside space of a tubular structure, such as the Golgi apparatus or endoplasmic reticulum.

Endocytosis

The process by which cells internalize substances from their surroundings.

Exocytosis

The process by which substances are expelled from a cell when vesicles fuse with the plasma membrane.