Cell Membranes and Signalling

These flashcards cover key concepts related to cell membranes and signalling, important for understanding their structure and function in biological systems.

Cystic fibrosis (CF)

A genetic disease caused by mutations in the CFTR gene, leading to thick mucus buildup and respiratory issues.

CFTR (Cystic Fibrosis Transmembrane Conductance Regulator)

A protein that acts as a chloride ion channel in the membranes of cells lining the lungs and intestines.

Fluid Mosaic Model

A model describing the structure of cell membranes, where integral proteins float in or on the fluid phospholipid bilayer.

Passive Transport

The movement of substances across a cell membrane without the use of energy, typically following a concentration gradient.

Active Transport

The process of moving molecules across a membrane from a region of lower concentration to a region of higher concentration, using energy.

Diffusion

The net movement of molecules from an area of higher concentration to an area of lower concentration, driven by a concentration gradient.

Facilitated Diffusion

A process of passive transport in which molecules move through a membrane via specific transport proteins.

Osmosis

The diffusion of water molecules across a selectively permeable membrane from an area of lower solute concentration to an area of higher solute concentration.

Endocytosis

The process by which cells ingest external material by engulfing it in a membrane-bound vesicle.

Exocytosis

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

Signal Transduction

The process by which a cell responds to signals (often chemical) by converting the signal into a functional response.

Membrane Receptor

A protein located on the cell membrane that binds to signaling molecules to initiate a cellular response.

Membrane Asymmetry

The condition where the lipid and protein composition is different between the inner and outer leaflets of the lipid bilayer.

Integral Membrane Proteins

Proteins that span the entire lipid bilayer, involved in various functions like transport and signal transduction.

Peripheral Membrane Proteins

Proteins that are attached to the exterior or interior surfaces of the membrane, not embedded within the lipid bilayer.

Phospholipid Bilayer

A double layer of phospholipids that makes up the basic structure of cell membranes, with hydrophobic tails facing inwards and hydrophilic heads facing outwards.