AP Biology Cell Membrane Flashcard

Front

What is the primary function of the cell membrane?

Back

The cell membrane regulates what enters and exits the cell, providing a barrier and maintaining homeostasis.

Front

What are phospholipids and their role in the cell membrane?

Back

Phospholipids are molecules with a hydrophilic (water-attracting) head and two hydrophobic (water-repelling) tails, forming a bilayer that makes up the cell membrane.

Front

What does selectively permeable mean in the context of cell membranes?

Back

Selectively permeable means that the cell membrane allows certain substances to pass through while blocking others.

Front

How do unsaturated phospholipids affect membrane fluidity?

Back

Unsaturated phospholipids have kinks in their tails that prevent tight packing, increasing membrane fluidity.

Front

What is the difference between integral and peripheral proteins?

Back

Integral proteins span the membrane and are involved in transport, while peripheral proteins are attached to the surface and play roles in signaling and maintaining the cell's shape.

Front

What is phagocytosis?

Back

Phagocytosis is the process by which a cell engulfs large particles or cells, such as bacteria, using its membrane.

Front

What is the role of cholesterol in the cell membrane?

Back

Cholesterol helps to stabilize the membrane's fluidity, making it less permeable to very small water-soluble molecules that might otherwise pass freely through.

Front

What is diffusion and how does it relate to cell membranes?

Back

Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration, and it occurs across cell membranes for small, nonpolar molecules.

Front

What is osmosis?

Back

Osmosis is the diffusion of water across a selectively permeable membrane, moving from an area of lower solute concentration to an area of higher solute concentration.

Front

What are transmembrane proteins?

Back

Transmembrane proteins are integral proteins that span the entire membrane and are involved in transporting substances across the membrane.