Question 1

Which of the following statements about the structure of fatty acids is CORRECT?

Accepted Answer

Fatty acids are carboxylic acids with hydrocarbon tails ranging from 4 to 36 carbons.

Question 2

Which of the following best explains why triacylglycerols are more efficient energy storage molecules than glycogen?

Accepted Answer

Triacylglycerols are hydrophobic and unhydrated, so they do not require water for storage.

Question 3

A fatty acid with the nomenclature 18:2(Δ9,12) is best described as:

Accepted Answer

An unsaturated fatty acid with 18 carbons and double bonds at carbons 9 and 12.

Question 4

Which of the following is a consequence of partial hydrogenation of vegetable oils?

Accepted Answer

It converts some cis double bonds to trans double bonds.

Question 5

Which of the following best describes the amphipathic nature of membrane lipids?

Accepted Answer

They have both hydrophobic and hydrophilic regions.

Question 6

Which of the following is TRUE regarding omega-3 (ω-3) fatty acids?

Accepted Answer

The first double bond is between C-3 and C-4 from the methyl (ω) end.

Question 7

Which of the following is a function of biological waxes in nature?

Accepted Answer

They act as water repellents and energy stores.

Question 8

Which of the following statements about sphingolipids is CORRECT?

Accepted Answer

Sphingolipids contain sphingosine as their backbone.

Question 9

Which of the following is the correct product of phospholipase D degradation of phosphatidylethanolamine?

Accepted Answer

Phosphatidate and ethanolamine

Question 10

Which of the following best describes the role of cholesterol in animal cell membranes?

Accepted Answer

It modulates membrane fluidity and serves as a precursor for steroid hormones.

Question 11

Which of the following statements about eicosanoids is FALSE?

Accepted Answer

They are classified as neither prostaglandins nor thromboxanes.

Question 12

A patient with a deficiency in lysosomal enzymes that degrade gangliosides would most likely accumulate which of the following in their cells?

Accepted Answer

Gangliosides

Question 13

Which of the following vitamins is essential for the formation of active prothrombin in blood clotting?

Accepted Answer

Vitamin K

Question 14

Which of the following is a correct statement about the function of dolichols?

Accepted Answer

They activate and anchor sugars to cellular membranes for biosynthesis.

Question 15

Which of the following best describes the effect of trans fatty acids on human health?

Accepted Answer

They raise LDL cholesterol and increase the body’s inflammatory response.

Question 16

Which of the following is a function of vitamin E (tocopherols) in biological systems?

Accepted Answer

They act as biological antioxidants.

Question 17

Which of the following is TRUE regarding the structure of a ganglioside?

Accepted Answer

It contains a ceramide backbone and one or more sialic acid residues.

Question 18

Which of the following best describes the function of bile acids in the digestive system?

Accepted Answer

They emulsify dietary fats to make them accessible to digestive lipases.

Question 19

Which of the following is a correct description of the action of phospholipase C on phosphatidylinositol 4,5-bisphosphate (PIP$$_2$$)?

Accepted Answer

It releases inositol 1,4,5-trisphosphate (IP$$_3) $$and diacylglycerol.

Question 20

Which of the following statements about natural pigments is TRUE?

Accepted Answer

They are often lipids with conjugated double bonds, allowing absorption of visible light.

Ch 10: Lipids – Structure, Function, and Biological Roles

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