Question 1

Which of the following best explains why water has a high surface tension?

Accepted Answer

Hydrogen bonds between water molecules create a cohesive force at the surface.

Question 2

A scientist discovers a molecule composed of only carbon and hydrogen atoms arranged in rings. Which class of organic molecules does this most likely belong to?

Accepted Answer

Hydrocarbons

Question 3

Which of the following statements about covalent bonds is correct?

Accepted Answer

Covalent bonds are formed when atoms share pairs of electrons.

Question 4

A solution has a pH of 4. How many times more acidic is it than a solution with a pH of 7?

Accepted Answer

$$10^3$$

Question 5

Which property of water allows it to moderate temperature in living organisms?

Accepted Answer

Its high specific heat due to hydrogen bonding

Question 6

Which of the following is NOT a function of nucleic acids?

Accepted Answer

Speed up chemical reactions

Question 7

A protein is exposed to extreme heat and loses its three-dimensional structure. What is this process called?

Accepted Answer

Denaturation

Question 8

Which of the following best describes a buffer in biological systems?

Accepted Answer

A substance that neutralizes acids and bases to maintain pH

Question 9

Which of the following is a correct pairing of nitrogenous bases in DNA?

Accepted Answer

Guanine pairs with Cytosine

Question 10

Which of the following statements about phospholipids is true?

Accepted Answer

Phospholipids form a bilayer in water with hydrophilic heads facing outward.

Question 11

Which of the following is a trace element in the human body?

Accepted Answer

Magnesium

Question 12

What is the main function of fats in biological systems?

Accepted Answer

Energy storage

Question 13

Which of the following best describes a dehydration reaction?

Accepted Answer

A reaction that joins monomers to form polymers by removing a water molecule

Question 14

Which of the following is true about the structure of DNA?

Accepted Answer

DNA molecules have two polynucleotides spiraling around an imaginary axis forming a double helix.

Question 15

Which of the following is a property of water that facilitates life?

Accepted Answer

Expansion upon freezing

Question 16

A molecule is described as hydrophobic. What does this mean?

Accepted Answer

It repels water and does not dissolve easily.

Question 17

Which of the following is NOT a characteristic of lipids?

Accepted Answer

They are composed of amino acids.

Question 18

Which of the following best describes the difference between a molecule and a compound?

Accepted Answer

A molecule is made of two or more atoms bonded together, while a compound is made of two or more different atoms bonded together in a fixed ratio.

Question 19

Which of the following is true about enzymes?

Accepted Answer

Enzymes are special proteins that speed up chemical reactions.

Question 20

Which of the following best explains why unsaturated fatty acids are typically found in plant and fish fats?

Accepted Answer

They contain double bonds that cause kinks in the hydrocarbon chains.

Foundations of General Biology: Atoms, Water, Carbon, and Biological Macromolecules

Guida di studio - Domande di pratica

Study guide - Flashcard