Cholesterol Structure (Part 1 2)

The video discusses cholesterol, a crucial lipid in cell membranes, highlighting its structure, functions, and role in membrane stability. Cholesterol's hydrophobic nature and its interaction with phospholipids are explained, emphasizing its impact on membrane rigidity and fluidity. The video also touches on how environmental factors like temperature influence cholesterol's role in membranes.

What is one of the primary functions of cholesterol in the body?

• It is a structural component of DNA.

• It acts as a neurotransmitter.

• It is a primary source of energy.

• It stabilizes cell membranes.

Which part of the cholesterol molecule is responsible for its hydrophobic nature?

• The phosphate group

• The carbon and hydrogen rings

• The nitrogen base

• The hydroxyl group

How does cholesterol orient itself in the cell membrane?

• Below the phospholipid tails

• Parallel to the phospholipid tails

• Perpendicular to the phospholipid tails

• Above the phospholipid heads

What type of bond does the hydroxyl group of cholesterol form with the phospholipid head?

• Metallic bond

• Hydrogen bond

• Covalent bond

• Ionic bond

What effect does cholesterol have on membrane stability?

• It increases membrane stability.

• It makes the membrane more permeable.

• It has no effect on membrane stability.

• It decreases membrane stability.

What is the role of Van der Waals forces in cholesterol's interaction with phospholipids?

• They decrease membrane stability.

• They stabilize the membrane structure.

• They increase membrane permeability.

• They have no effect on the membrane.

How does cholesterol affect the entropy of the membrane?

• It increases membrane entropy.

• It decreases membrane entropy.

• It has no effect on membrane entropy.

• It makes the membrane more chaotic.

In which climate would you expect to find more cholesterol in cell membranes?

• Desert climates

• Tropical climates

• Polar climates

• Temperate climates

Why is there less cholesterol in the membranes of people living in colder climates?

• To increase membrane fluidity

• To increase membrane permeability

• To decrease membrane permeability

• To decrease membrane fluidity

What is the effect of high temperatures on membrane fluidity?

• It increases membrane fluidity.

• It has no effect on membrane fluidity.

• It makes the membrane more rigid.

• It decreases membrane fluidity.