Question 1

Which structure is shown in the first image (the four fused rings)?

Accepted Answer

A steroid nucleus

Question 2

Based on the lipid classification diagram (second image), which of the following lipids does NOT contain fatty acids?

Accepted Answer

Steroids

Question 3

The molecule shown in the third image is lauric acid. Which of the following best describes lauric acid?

Accepted Answer

A saturated fatty acid

Question 4

The fourth image shows glyceryl trioleate (triolein). What type of reaction would convert this molecule into three fatty acids and glycerol?

Accepted Answer

Hydrolysis

Question 5

Refer to the table of fatty acids (fifth image). Which fatty acid is most likely to be solid at room temperature?

Accepted Answer

Stearic acid

Question 6

The sixth image shows the structure of oleic acid. Which of the following statements is true about this molecule?

Accepted Answer

It is a monounsaturated fatty acid

Question 7

In the omega-6 fatty acids image, what does the '6' in omega-6 refer to?

Accepted Answer

The position of the first double bond from the methyl end

Question 8

In the omega-3 fatty acids image, which fatty acid is most abundant in cold-water fish?

Accepted Answer

Eicosapentaenoic acid (EPA)

Question 9

The wax structure (ninth image) is best described as:

Accepted Answer

An ester of a long-chain fatty acid and a long-chain alcohol

Question 10

The reaction in the tenth image shows the formation of a triglyceride. What type of bond is formed between glycerol and fatty acids?

Accepted Answer

Ester bond

Question 11

The polar bear in the eleventh image relies on which type of lipid for energy storage during hibernation?

Accepted Answer

Triacylglycerols

Question 12

According to the bar graph (twelfth image), which oil has the highest percentage of polyunsaturated fatty acids?

Accepted Answer

Safflower oil

Question 13

The reaction in the thirteenth image is an example of:

Accepted Answer

Hydrogenation

Question 14

The fourteenth image shows a common food product made by partial hydrogenation of vegetable oils. What is a health risk associated with this process?

Accepted Answer

Formation of trans fats, which raise LDL cholesterol

Question 15

The two line-angle structures in the fifteenth and sixteenth images highlight a difference between cis and trans isomers. Which statement is correct?

Accepted Answer

The cis isomer has bulky groups on the same side of the double bond, causing a kink

Question 16

The hydrolysis reaction in the seventeenth image requires which of the following?

Accepted Answer

Water and an acid or enzyme

Question 17

The saponification reaction in the eighteenth image produces which of the following products?

Accepted Answer

Glycerol and sodium salts of fatty acids (soap)

Question 18

According to the summary table (nineteenth image), which reaction type converts a triacylglycerol into three fatty acids and glycerol?

Accepted Answer

Hydrolysis

Question 19

The reaction in the twentieth image shows the hydrolysis of glyceryl trilaurate by lipase. What are the products?

Accepted Answer

Glycerol and three lauric acid molecules

Lipids: Structure, Classification, and Biological Functions

Study Guide - Practice Questions