Cell Membrane Structure and Function

Flashcards about cell membrane structure and function.

What is the main structural component of cell membranes?

A lipid bilayer.

Name three key functions of the plasma membrane.

Compartmentalization, selective permeability, and transport of solutes.

What is a key characteristic of membrane lipids?

They are amphipathic, having both hydrophilic and hydrophobic regions.

Name the three main types of membrane lipids.

Phosphoglycerides, sphingolipids, and cholesterol.

How do desaturases contribute to membrane fluidity?

They catalyze the formation of double bonds in fatty acids, increasing unsaturation and reducing rigidity.

Describe the function of flippases.

Enzymes that translocate lipids from one layer to another within the lipid bilayer to maintain lipid asymmetry.

What is the function of the erythrocyte's membrane skeleton?

Provides resistance, elasticity, and flexibility, allowing red blood cells to deform without breaking.

What is the key function of the Na/K-ATPase pump?

Pumps 3 Na+ ions out of the cell and 2 K+ ions into the cell for each ATP hydrolyzed, maintaining electrochemical gradients.

Define osmosis.

The diffusion of water across a semipermeable membrane from a region of lower solute concentration to a region of higher solute concentration.

What is the role of aquaporins?

Channel proteins that facilitate the rapid passage of water across cell membranes.

How can mutations in aquaporin genes affect humans?

Mutations can cause nephrogenic diabetes insipidus.

What is the function of the receptor for acetylcoline?

When acetylcholine binds to the receptor, the channel opens and allows ions to pass through, initiating a response

Name two type of neurotransmitters

Glutamate(excitatory) and GABA(inhibitory)

How does temperature affect membrane fluidity?

Low temperatures decrease the fluidity of the membrane.

What are three types of membrane proteins?

Integral, peripheral, and lipid-anchored