Question 1

Which of the following statements about the bonds in water is correct?

Accepted Answer

The bonds within a water molecule are polar covalent because electrons spend more time around the oxygen atom, generating a partial negative charge near the oxygen atom.

Question 2

A protein hormone such as luteinizing hormone (LH) is exposed to high temperatures. Which of the following best describes what happens at the molecular level?

Accepted Answer

The hydrogen bonds stabilizing the protein's tertiary structure break, leading to denaturation and loss of function.

Question 3

Which of the following is a consequence at the organismal level if luteinizing hormone (LH) is denatured by high temperatures?

Accepted Answer

Disruption of reproductive processes such as ovulation and testosterone production.

Question 4

A bacterial species attacks single-stranded binding proteins (SSBs) in white blood cells. What is the immediate effect on DNA replication?

Accepted Answer

The DNA strands would re-anneal, preventing replication from proceeding.

Question 5

Which of the following best explains why some insects can walk on water?

Accepted Answer

Water's high surface tension, due to hydrogen bonding between water molecules, supports the insect's weight.

Question 6

Which of the following correctly describes the difference between saturated and unsaturated fats?

Accepted Answer

Unsaturated fats contain at least one double or triple bond, and thus do not have the maximum number of hydrogens in their fatty acid chains. Saturated fats have only single bonds in their fatty acid chains, and thus have the maximum number of hydrogens in their fatty acid chains.

Question 7

During the formation of nucleic acid polymers, what is removed from the monomers to form the polymer?

Accepted Answer

A water molecule ($$\mathrm{H_2O}) is $$removed during the dehydration synthesis reaction.

Question 8

Which of the following best describes the orientation of phospholipids in a cell membrane?

Accepted Answer

The hydrophobic fatty acid chains face the interior of the membrane, while the hydrophilic head groups line the exterior surface.

Question 9

A virus causes DNA Helicase to become over-active in a host cell. What is a likely consequence?

Accepted Answer

DNA replication increases due to more frequent unwinding of the double helix.

Question 10

Which of the following is a function of cholesterol in animal cells?

Accepted Answer

Cholesterol contributes to membrane flexibility, hormone production, and regulation of Vitamin D synthesis.

Question 11

Which property of carbon makes it essential for organic life?

Accepted Answer

Carbon can form up to four covalent bonds, allowing it to create a variety of structures including long chains and rings.

Question 12

Which of the following best describes the function of single-stranded binding proteins (SSBs) during DNA replication?

Accepted Answer

They stabilize the unwound DNA strands and prevent them from re-annealing.

Question 13

Which of the following statements about glycosidic linkages is correct?

Accepted Answer

$$\alpha 1$$,4 glycosidic linkages and $$\beta 1$$,4 glycosidic linkages are covalent bonds formed during dehydration of carbohydrate monomers, but $$\alpha 1$$,4 glycosidic linkages are easier to break.

Question 14

Which of the following is an example of water’s property of adhesion?

Accepted Answer

The attraction between water molecules and the molecules of another substance, such as water climbing up a plant stem.

Question 15

Atoms of the same element that vary in the number of neutrons are called:

Accepted Answer

Isotopes

Question 16

Which of the following is FALSE regarding chemical bonds?

Accepted Answer

Ionic bonds involve the transfer of protons from one atom to another.

Question 17

Which of the following best explains why a virus would want to make DNA Helicase over-active in a host cell?

Accepted Answer

To increase DNA replication, thereby increasing the amount of viral genomes created.

Question 18

Which of the following is removed during the dehydration synthesis of a nucleic acid polymer?

Accepted Answer

A water molecule ($$\mathrm{H_2O})$$

Question 19

Which of the following best describes the function of DNA Helicase?

Accepted Answer

To separate the two strands of the double helix during DNA replication.

Question 20

Which of the following terms applies to a molecule that interacts with water because it contains a full positive charge on one of its atoms?

Accepted Answer

Hydrophilic

Unit 1 Biology Review – Step-by-Step Study Guidance

Study Guide - Practice Questions

Study Guide - Flashcards