Cell Membrane & Diffusion

Front

What term describes the ability of the cell membrane to allow only certain materials to move into and out of the cell?

Back

Semi-permeable

Front

What type of structure is represented by a phospholipid?

Back

A molecule that forms the basic structure of the cell membrane, consisting of a hydrophilic (water-attracting) head and two hydrophobic (water-repelling) tails.

Front

What are the small units that make up the cell membrane?

Back

Phospholipids.

Front

What does the term 'Hydrophobic' mean in relation to cell membranes?

Back

It refers to substances that repel water.

Front

In which direction does diffusion move molecules?

Back

With the concentration gradient.

Front

What is the primary function of the cell membrane?

Back

To protect the cell and regulate the movement of substances in and out.

Front

What is the role of cholesterol in the cell membrane?

Back

To maintain membrane fluidity and stability.

Front

What is the difference between passive and active transport?

Back

Passive transport does not require energy and moves substances down their concentration gradient, while active transport requires energy to move substances against their concentration gradient.

Front

What is osmosis?

Back

The diffusion of water across a semi-permeable membrane.

Front

What is the significance of the fluid mosaic model?

Back

It describes the structure of the cell membrane as a mosaic of various proteins that float in or on the fluid lipid bilayer.