Question 1

Which of the following statements best explains why carbon is considered a versatile element in organic chemistry?

Accepted Answer

Carbon can share electrons with other atoms in up to four covalent bonds, allowing for a diversity of molecular structures.

Question 2

A dehydration reaction is crucial in the formation of biological polymers. What is the main result of a dehydration reaction?

Accepted Answer

It links two monomers together and removes a molecule of water.

Question 3

Which of the following is NOT a function of carbohydrates in animals?

Accepted Answer

Building material for much of the plant body.

Question 4

Glucose and fructose have the same molecular formula but different structures. What term describes this relationship?

Accepted Answer

Isomers

Question 5

Which polysaccharide is the most abundant organic compound on Earth and cannot be broken down by any enzyme produced by animals?

Accepted Answer

Cellulose

Question 6

A patient is diagnosed with lactose intolerance. Which process is failing in their digestive system?

Accepted Answer

Lactose is not being broken down and absorbed in the small intestine.

Question 7

Which of the following best describes the structure of a fat (triglyceride) molecule?

Accepted Answer

A glycerol molecule joined with three fatty acid molecules via a dehydration reaction.

Question 8

What is the main difference between saturated and unsaturated fats?

Accepted Answer

Unsaturated fats have fewer than the maximum number of hydrogens at the double bond.

Question 9

Which of the following is a function of proteins in living organisms?

Accepted Answer

Providing structural support, catalyzing chemical reactions, and transporting substances.

Question 10

Amino acids are the monomers of proteins. Which group is variable among different amino acids and determines their chemical properties?

Accepted Answer

Side chain (R group)

Question 11

Which of the following statements about nucleic acids is correct?

Accepted Answer

DNA and RNA are both made of nucleotides consisting of a sugar, a phosphate, and a nitrogenous base.

Question 12

Which base pairing occurs in DNA due to the functional groups hanging off the bases?

Accepted Answer

$$A$$ pairs with $$T$$, $$G$$ pairs with $$C$$

Question 13

Which process reverses a dehydration reaction and is essential for digestion?

Accepted Answer

Hydrolysis

Question 14

Which of the following is a real-world consequence of consuming a diet high in saturated fats?

Accepted Answer

Increased risk of atherosclerosis due to lipid-containing plaques in blood vessels.

Question 15

Which of the following is a correct description of a polymer?

Accepted Answer

A molecule made by linking together many smaller molecules called monomers.

Question 16

Which of the following is NOT a category of large biological molecules found in all living creatures?

Accepted Answer

Vitamins

Question 17

A scientist discovers a molecule with a carbon skeleton arranged in four fused rings. This molecule is most likely a:

Accepted Answer

Steroid

Question 18

Which of the following statements about the genetic basis of lactose intolerance is supported by scientific research?

Accepted Answer

Lactose intolerance can be correlated with a single nucleotide located near, but not within, the lactase gene.

Question 19

Which of the following is a correct multi-step application of macromolecule concepts: If a person eats a meal containing starch, what sequence of reactions occurs to make the glucose available to their cells?

Accepted Answer

Starch is broken down by hydrolysis into glucose monomers, which are then absorbed and used for cellular work.

Chapter 3: The Molecules of Life – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards