Chapter 26 Practice Test

Question 1

What are the structural units of proteins?

Answer 1

Amino acids

Question 2

Which of the following shows a primary structure for a protein?

Answer 2

Question 3

Which of the following is a catalyst in biochemical reactions?

Answer 3

Enzyme

Question 4

Which of the following elements would be found in the polar R group of a protein?

Answer 4

N

Question 5

Which of the following shows an α-helix structure for a protein?

Answer 5

blue helix

Question 6

Which of the following is an amide functional group?

Answer 6

Question 7

Which of the following elements would be found in a non-polar R group?

Answer 7

C

Question 8

Which base does adenine bond with?

Answer 8

thymine

Question 9

What is the complimentary DNA strand for the following sequence?

T–T–C–G–A–C–G–A

Answer 9

A–A–G–C–T–G–C–T

Question 10

What type of bond is responsible for base-pairing in DNA?

Answer 10

pi

Question 11

Which of the following is NOT a part of RNA?

Answer 11

Deoxyribose

Question 12

How many hydrogen bonds link guanine and cytosine?

Answer 12

3

Question 13

What type of sugar is found in RNA?

Answer 13

Ribose

Question 14

Which statement about carbohydrates is not correct?

Answer 14

A simple sugar molecule, such as glucose or fructose, is a polymer whose components are linked in a long, linear fashion.

Question 15

Aldehydes and ketones are constituent components of carbohydrates. They are either exposed in the open form of the carbohydrate or they are masked in the closed form of the carbohydrate. The drawing shows how an aldehyde reacts with an alcohol. It also shows the reverse reaction, in which an aldehyde and an alcohol are produced.
Which statement about these reactions is not correct?

Answer 15

The OH group in the alcohol product of reaction 2 is the same as the OH group in the reactant of reaction 2.

Question 16

A glucose sugar molecule has an aldehyde that is masked or hidden in its structure. The diagram shows how a closed form glucose molecule becomes an open form glucose molecule.
Which statement about this event is not correct?

Answer 16

The oxygen atom at the bottom of the closed glucose molecule eventually forms a new OH group in the product molecule.

Question 17

Look at starch (or amylose) and cellulose polymers.

Which statement about starch or cellulose is not correct?

Answer 17

Both starch and cellulose are comprised of linked glucose molecules. The only difference involves the elements (oxygen versus nitrogen) that actually link the glucose molecules.

Question 18

Carbohydrates are __________________

Answer 18

a class of biological molecules composed of polyhydroxylated aldehydes or ketones.

Question 19

Ribose is an important sugar component of RNA, which is a nucleic acid involved in protein synthesis in the body. Deoxyribose is an important sugar component of DNA, a nucleic acid that stores the body’s genetic information.
Which statement about these carbohydrates is not correct?

Answer 19

The formula for ribose is C5H10O4.

Question 20

Which statement about lipids is not correct?

Answer 20

Lipids provide less energy than glucose.

Question 21

Which statement about glucose and triglycerides is not correct?

Answer 21

Triglycerides are already mostly oxidized.

Question 22

Which statement about saturated or unsaturated triglycerides is not correct?

Answer 22

Unsaturated fats in your diet can lead to solid masses in arteries.

Question 23

Which statement about cholesterol is not correct?

Answer 23

Cholesterol is transported to other parts of the body by lipoproteins. Cholesterol is flushed from the body through proteins other than lipoproteins.

Question 24

Lipids are _________________

Answer 24

biological molecules that are soluble in organic solvents but insoluble or sparingly soluble in water.

Question 25

The principal difference between saturated and unsaturated triglycerides is ______________

Answer 25

the presence (or absence) of one or more alkene group.