Cell membrane and Diffusion

Front

What is diffusion?

Back

Diffusion is the process by which molecules spread from areas of high concentration to areas of low concentration.

Front

What does it mean for a membrane to be selectively permeable?

Back

A selectively permeable membrane allows some molecules to cross while preventing others from doing so.

Front

What does hydrophilic mean?

Back

Hydrophilic means 'water-loving' and refers to substances that can interact with water.

Front

What part of a phospholipid is hydrophilic?

Back

The phosphate 'head' of a phospholipid is hydrophilic.

Front

What does hydrophobic mean?

Back

Hydrophobic means 'water-fearing' and refers to substances that do not interact well with water.

Front

What is osmosis?

Back

Osmosis is the diffusion of water molecules across a selectively permeable membrane.

Front

What is the difference between active transport and passive transport?

Back

Active transport requires energy to move molecules against their concentration gradient, while passive transport does not.

Front

What is a phospholipid?

Back

A phospholipid is a molecule that makes up the cell membrane, consisting of a hydrophilic 'head' and two hydrophobic 'tails'.

Front

What is the role of cholesterol in the cell membrane?

Back

Cholesterol helps to stabilize the cell membrane's fluidity and structure.

Front

What is the fluid mosaic model?

Back

The fluid mosaic model describes the structure of the cell membrane as a mosaic of various proteins floating in or on the fluid lipid bilayer.