Cell Plasma Membrane Structure and Function

A type of active transport that uses energy directly from ATP hydrolysis to move substances against their concentration gradient.

A key example of primary active transport. It pumps 3 Na+ ions out of the cell and 2 K+ ions into the cell.

A type of active transport that indirectly uses energy from ATP hydrolysis. It couples the movement of one substance down its concentration gradient with the movement of another substance against its concentration gradient.

A type of secondary active transport where two substances move in the same direction across the membrane.

A type of secondary active transport where two substances move in opposite directions across the membrane.

The cell membrane is a selectively permeable barrier that controls what enters and leaves the cell. It's made up of a mix of lipids (like phospholipids) and proteins.

Phospholipids are the most abundant type of lipid in cell membranes. They have a hydrophilic head (attracted to water) and two hydrophobic tails (repelled by water).

Phospholipids arrange themselves into a bilayer in water. The hydrophilic heads face outwards (towards water), and the hydrophobic tails face inwards (away from water).

The cell membrane is selectively permeable, meaning some substances can pass through easily, while others are blocked. This controls the environment inside the cell.

The cell membrane is also involved in cell recognition. This is how the immune system tells its own cells from foreign invaders.

The arrangement of molecules in the cell membrane creates a charge difference across the membrane (called the membrane potential). This is crucial for many cell processes.

Enzymes are proteins that help speed up chemical reactions. Some enzymes sit within the cell membrane and assist with important processes.

The cell membrane plays a critical role in communication between cells. It receives signals, interprets them, and then triggers responses within the cell.

The plasma membrane is a dynamic structure where components like lipids and proteins move laterally across the membrane.

The movement of molecules or ions across a membrane from a region of high concentration to a region of low concentration, facilitated by membrane transport proteins. It does not require energy from ATP.

The movement of substances across a membrane against their concentration gradient, requiring energy from ATP hydrolysis.

A type of membrane protein that spans the entire lipid bilayer, connecting the extracellular side to the intracellular side.

Integral membrane proteins that extend across the membrane only once. Often form a-helical structures.

Integral membrane proteins that traverse the membrane multiple times, forming multiple a-helical segments.

A type of transmembrane protein that forms a barrel-like structure in the membrane, allowing molecules to pass through.

Integral membrane proteins that are attached to the membrane via lipid molecules.

Proteins that associate with the membrane through non-covalent interactions, and can be easily removed.

Cellular communication involves signalling molecules binding to specific receptor proteins located on the membrane.

The arrangement of phospholipid molecules in a membrane is not symmetrical, with different lipid compositions on the cytosolic and extracellular sides.

A phospholipid found primarily on the cytosolic side of the membrane, plays roles in protein kinase C activation and signaling during apoptosis.

A type of phospholipid found predominantly on the cytosolic side, involved in signaling pathways and protein binding.

Lipids with carbohydrate groups attached, found exclusively on the extracellular side of the membrane. They play significant roles in cell recognition and signaling.

A type of protein that links the extracellular matrix to the cytoskeleton, allowing for cell mobility.