Q: Given an atom with atomic number 17 and atomic mass 35, how many neutrons does it have?

$$\text{Neutrons} = 35 - 17 = 18$$

Q: A DNA sample contains 30% thymine. What percentage of guanine does it contain?

$$\text{A} = \text{T} = 30\%$$, so \text{A} + \text{T} = 60\%$$. Therefore, \text{G} + \text{C} = 40\%$$. \text{G} = 20\%$

Question 1

Which of the following best describes the difference between a population and a community in an ecosystem?

Accepted Answer

A population is a group of individuals of the same species in a given area, while a community includes all populations of different species in that area.

Question 2

A scientist is testing the effect of a new fertilizer on plant growth. She sets up three groups: one with no fertilizer, one with a standard fertilizer, and one with the new fertilizer. Which group serves as the negative control?

Accepted Answer

The group with no fertilizer

Question 3

Given an atom with atomic number 17 and atomic mass 35, how many neutrons does it have?

Accepted Answer

$$	ext{Neutrons} = 35 - 17 = 18$$

Question 4

Which of the following statements about water is correct?

Accepted Answer

Water is a polar molecule because oxygen is more electronegative than hydrogen, creating partial charges.

Question 5

If the pH of a solution changes from 7 to 5, how does the hydrogen ion concentration change?

Accepted Answer

It increases by 100 times

Question 6

Which functional group is responsible for the acidic properties of amino acids?

Accepted Answer

Carboxyl group ($$-\mathrm{COOH})$$

Question 7

Which of the following best explains why ice floats on liquid water?

Accepted Answer

Ice is less dense than liquid water because hydrogen bonds keep water molecules farther apart in the solid state.

Question 8

A DNA sample contains 30% thymine. What percentage of guanine does it contain?

Accepted Answer

$$	ext{A} = 	ext{T} = 30\%$$, so 	ext{A} + 	ext{T} = 60\%$$. Therefore, 	ext{G} + 	ext{C} = 40\%$$. 	ext{G} = 20\%$

Question 9

Which of the following is a property shared by all living organisms?

Accepted Answer

Order and regulation

Question 10

Which type of chemical bond is the strongest under physiological conditions?

Accepted Answer

Covalent bond

Question 11

Which organelle is responsible for producing ATP through cellular respiration?

Accepted Answer

Mitochondrion

Question 12

Which of the following best describes the difference between saturated and unsaturated fatty acids at room temperature?

Accepted Answer

Saturated fatty acids are solid, unsaturated fatty acids are liquid.

Question 13

Which of the following is NOT found in animal cells but is present in plant cells?

Accepted Answer

Chloroplasts

Question 14

A protein loses its three-dimensional structure and function after being exposed to high heat. What is this process called?

Accepted Answer

Denaturation

Question 15

Which of the following best describes the role of buffers in biological systems?

Accepted Answer

Buffers minimize changes in concentrations of $$\mathrm{H}^+$$ and $$\mathrm{OH}^-$$ ions.

Question 16

Which cytoskeletal element is primarily responsible for muscle contraction and cell movement?

Accepted Answer

Microfilaments

Question 17

Which of the following is a correct pairing of a functional group and its property?

Accepted Answer

Carboxyl group ($$-\mathrm{COOH}$$): acidic

Question 18

Which of the following best explains why carbon is able to form such a diversity of organic molecules?

Accepted Answer

Carbon has four valence electrons and can form four covalent bonds.

Question 19

Which of the following is a correct description of a dehydration reaction?

Accepted Answer

A reaction that joins monomers to form polymers by removing water.

Question 20

A scientist discovers a new molecule with the formula $$\mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6. $$Which class of biomolecule does this most likely belong to?

Accepted Answer

Monosaccharide

BIO 121: Foundations of Biology – Study Guide (Chapters 1–6)

Study Guide - Practice Questions

Study Guide - Flashcards