Question 1

Which subatomic particle is responsible for determining the atomic number of an element, and how does this relate to the element's identity?

Accepted Answer

Protons; they determine the element's atomic number and identity.

Question 2

A carbon atom has 6 protons, 8 neutrons, and 6 electrons. What is its mass number, and what is this atom called?

Accepted Answer

Mass number is 14; it is a carbon isotope.

Question 3

Which of the following best describes an ionic bond?

Accepted Answer

A bond formed by the transfer of electrons from one atom to another.

Question 4

Given a sodium atom (Na) with 11 protons and a chlorine atom (Cl) with 17 protons, what happens when they form an ionic bond?

Accepted Answer

Sodium loses an electron and becomes positively charged; chlorine gains an electron and becomes negatively charged.

Question 5

Which of the following best explains why water is a polar molecule?

Accepted Answer

Oxygen is more electronegative, creating a partial negative charge near the oxygen and a partial positive charge near the hydrogens.

Question 6

What type of bond holds the two hydrogen atoms to the oxygen atom within a single water molecule?

Accepted Answer

Covalent bond

Question 7

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

Accepted Answer

High specific heat due to hydrogen bonding

Question 8

If a solution has a pH of 4 and another has a pH of 7, how many times more acidic is the first solution compared to the second?

Accepted Answer

$$1000$$

Question 9

How many valence electrons does a carbon atom have?

Accepted Answer

$$4$$

Question 10

Which of the following is an example of a dehydration reaction?

Accepted Answer

Joining two amino acids to form a dipeptide and releasing a molecule of water.

Question 11

Which functional group is present in all amino acids?

Accepted Answer

Carboxyl group

Question 12

Which of the following best describes an isomer?

Accepted Answer

Molecules with the same molecular formula but different structures.

Question 13

Which of the following best distinguishes a saturated fatty acid from an unsaturated fatty acid?

Accepted Answer

Unsaturated fatty acids have one or more double bonds between carbon atoms.

Question 14

Which of the following is NOT a component of a nucleotide?

Accepted Answer

A glycerol molecule

Question 15

A scientist is testing the effect of a new fertilizer on plant growth. Which of the following is the dependent variable?

Accepted Answer

The growth of the plants measured in height

Question 16

If a mutation changes a single amino acid in the active site of an enzyme, what is the most likely effect on the enzyme's function?

Accepted Answer

The enzyme's function may be reduced or lost due to altered substrate binding.

Question 17

Which of the following best describes the primary structure of a protein?

Accepted Answer

The sequence of amino acids in a polypeptide chain.

Question 18

Which of the following is a correct comparison between starch and cellulose?

Accepted Answer

Both are composed of glucose monomers, but starch is used for energy storage in plants while cellulose provides structural support.

Question 19

Which of the following best describes a hydrolysis reaction?

Accepted Answer

A reaction that breaks a molecule into two smaller molecules by adding water.

Question 20

A solution has a hydrogen ion concentration of $$1 	imes 10$$^{-5}$$ M. What is its pH?

Accepted Answer

$$5$$

General Biology: Atomic Structure, Chemical Bonds, Macromolecules, and Experimental Design

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