Question 1

Which of the following best describes the scientific method as used in biology?

Accepted Answer

A systematic process for testing hypotheses through observation and experimentation.

Question 2

Which property of water allows it to moderate Earth's climate by absorbing heat without a large increase in temperature?

Accepted Answer

High specific heat

Question 3

A buffer solution is important in biological systems because it:

Accepted Answer

Maintains a stable pH by neutralizing added acids or bases.

Question 4

Which equation correctly represents the relationship between atomic number ($Z$), mass number ($A$), and number of neutrons ($N$) in an atom?

Accepted Answer

$A = Z + N$

Question 5

Which of the following is NOT a polymer?

Accepted Answer

Glucose

Question 6

A molecule of water ($\mathrm{H_2O}$) is held together by which type of chemical bond?

Accepted Answer

Covalent bond

Question 7

Which functional group is present in all amino acids and is responsible for their acidic properties?

Accepted Answer

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

Question 8

Which statement best explains why ice floats on liquid water?

Accepted Answer

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

Question 9

Which of the following best describes the role of carbon in organic molecules?

Accepted Answer

Carbon can form four covalent bonds, allowing for diverse molecular structures.

Question 10

Which of the following is the correct formula for calculating the pH of a solution given the hydrogen ion concentration $[\mathrm{H^+}]$?

Accepted Answer

$\mathrm{pH} = -\log_{10} [\mathrm{H^+}]$

Question 11

Which level of protein structure is primarily determined by the sequence of amino acids?

Accepted Answer

Primary structure

Question 12

Which of the following best explains why saturated fatty acids are solid at room temperature while unsaturated fatty acids are liquid?

Accepted Answer

Unsaturated fatty acids have double bonds that prevent tight packing.

Question 13

Which of the following is a correct description of a phosphodiester bond?

Accepted Answer

A bond between the phosphate group and the sugar in nucleic acids.

Question 14

Which of the following statements about enzymes is correct?

Accepted Answer

Enzymes lower the activation energy required for a reaction.

Question 15

Which of the following is a correct example of a dehydration synthesis reaction?

Accepted Answer

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

Question 16

Which of the following best describes the difference between DNA and RNA?

Accepted Answer

DNA contains deoxyribose sugar, while RNA contains ribose sugar.

Question 17

Which of the following is a correct statement about hydrogen bonds?

Accepted Answer

Hydrogen bonds form between polar molecules, such as between water molecules.

Question 18

Which of the following is a correct example of a real-world application of the concept of buffers?

Accepted Answer

The bicarbonate buffer system maintaining blood pH in humans.

Question 19

Which of the following best explains the importance of the three-dimensional structure of proteins?

Accepted Answer

It determines the protein's function by allowing specific interactions with other molecules.

Question 20

Which of the following is a correct description of the role of messenger RNA (mRNA) in cells?

Accepted Answer

mRNA provides instructions for protein synthesis by conveying genetic information from DNA.

General Biology: Core Concepts and Study Guide

Study Guide - Practice Questions