Question 1

Which of the following statements best explains why lipids are insoluble in water?

Accepted Answer

Lipids are nonpolar molecules, and water is a polar solvent, so they do not mix due to the 'like dissolves like' principle.

Question 2

Which of the following is NOT a function of lipids in the human body?

Accepted Answer

Acting as enzymes to catalyze biochemical reactions

Question 3

A triacylglycerol undergoes hydrolysis. Which products are formed?

Accepted Answer

Glycerol and three fatty acid molecules

Question 4

Which type of lipid CANNOT undergo hydrolysis?

Accepted Answer

Steroids

Question 5

What is the main purpose of the commercial hydrogenation of oils?

Accepted Answer

To convert unsaturated oils into saturated fats, making them solid at room temperature

Question 6

Which of the following best describes a saturated fatty acid?

Accepted Answer

A fatty acid with only single bonds between carbon atoms

Question 7

Why are saturated fatty acids typically solid at room temperature, while unsaturated fatty acids are liquid?

Accepted Answer

Saturated fatty acids have straight chains that pack closely together, while unsaturated fatty acids have kinks due to double bonds that prevent tight packing.

Question 8

Which of the following statements about the iodine number test is correct?

Accepted Answer

It measures the degree of unsaturation in a fat or oil by determining how much iodine reacts with double bonds.

Question 9

Which of the following best describes the structure of a glycerophospholipid?

Accepted Answer

It has a polar head and two nonpolar tails, allowing it to interact with both polar and nonpolar substances.

Question 10

Which statement best explains why LDL is considered 'bad' cholesterol and HDL is considered 'good' cholesterol?

Accepted Answer

LDL transports cholesterol to tissues, which can lead to plaque buildup in arteries, while HDL removes cholesterol from tissues and transports it to the liver for excretion.

Question 11

Which of the following is a major component of cell membranes?

Accepted Answer

Glycerophospholipids

Question 12

Which of the following best describes the structure of a lipoprotein?

Accepted Answer

A polar surface with nonpolar inner contents, allowing transport of lipids in the bloodstream

Question 13

Which of the following best explains why the cell membrane is described as semi-permeable?

Accepted Answer

It allows some molecules to pass through while restricting others based on size, polarity, or charge.

Question 14

Which of the following substances is also found in cell membranes, in addition to glycerophospholipids?

Accepted Answer

Cholesterol

Question 15

Which of the following best describes passive transport across a cell membrane?

Accepted Answer

Movement of molecules from high to low concentration without energy input

Question 16

A patient is found to have high levels of LDL and low levels of HDL in their blood. What health risk does this combination most likely indicate?

Accepted Answer

Increased risk of atherosclerosis and cardiovascular disease

Question 17

Which of the following is an example of facilitated transport across a cell membrane?

Accepted Answer

Glucose moving into a cell via a protein channel, without energy input

Question 18

Which of the following reactions is the first step in the digestion of fats?

Accepted Answer

Hydrolysis

Question 19

A fatty acid contains two double bonds in its hydrocarbon chain. How is it classified?

Accepted Answer

Polyunsaturated

Question 20

Which of the following best describes active transport across a cell membrane?

Accepted Answer

Movement of molecules from low to high concentration using energy (ATP)

Chapter 15 Study Guide: Lipids

Study Guide - Practice Questions

Study Guide - Flashcards