Unit #4 Review A

Front

What is a phospholipid?

Back

A phospholipid is a molecule composed of a phosphate and glycerol head and two fatty acid chain tails.

Front

What are the two parts of a phospholipid called?

Back

Hydrophilic Head and Hydrophobic Tail.

Front

What is the process called when materials move across a membrane from low concentration to high concentration?

Back

Active Transport.

Front

What does it mean when a membrane is selectively permeable?

Back

It means that some molecules can cross the membrane while others cannot.

Front

What does hydrophilic mean?

Back

Hydrophilic means water-loving.

Front

What is the opposite of hydrophilic?

Back

Hydrophobic, which means water-fearing.

Front

What is osmosis?

Back

Osmosis is the movement of water across a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration.

Front

What is simple diffusion?

Back

Simple diffusion is the movement of molecules from an area of high concentration to an area of low concentration without the use of energy.

Front

What is the role of cholesterol in cell membranes?

Back

Cholesterol helps to stabilize the structure of the cell membrane and maintain its fluidity.

Front

What is the difference between active transport and passive transport?

Back

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