Question 1

Which of the following best explains why water is considered a 'universal solvent' in biological systems?

Accepted Answer

Because water molecules are polar, allowing them to surround and separate many ionic and polar substances.

Question 2

A scientist is studying a newly discovered organism and wants to classify it. The organism is multicellular, has a nucleus, and obtains nutrients by absorption. To which kingdom does this organism most likely belong?

Accepted Answer

Fungi

Question 3

Which of the following best describes the flow of genetic information in a eukaryotic cell?

Accepted Answer

$$DNA \rightarrow RNA \rightarrow Protein$$

Question 4

Which property of water allows insects, such as water striders, to walk on the surface of a pond?

Accepted Answer

Cohesion due to hydrogen bonding

Question 5

A student is asked to design an experiment to test the effect of light on plant growth. Which of the following is the best example of a controlled experiment?

Accepted Answer

Growing one plant in sunlight and another in darkness, keeping all other conditions the same.

Question 6

Which of the following statements about isotopes is correct?

Accepted Answer

Isotopes have the same number of protons but different numbers of neutrons.

Question 7

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

Accepted Answer

Carbon can form up to four covalent bonds with other atoms.

Question 8

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

Accepted Answer

Saturated fatty acids have no double bonds between carbon atoms, while unsaturated fatty acids have one or more double bonds.

Question 9

A molecule of ATP releases energy for cellular work when which of the following occurs?

Accepted Answer

A phosphate group is removed by hydrolysis.

Question 10

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

Accepted Answer

Ice is less dense than liquid water due to the hydrogen bonds forming a crystalline structure.

Question 11

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

Accepted Answer

Covalent bonds involve the sharing of electron pairs between atoms.

Question 12

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

Accepted Answer

Enzymes speed up chemical reactions by lowering the activation energy required.

Question 13

A student is given a diagram of a molecule and asked to identify it as DNA or RNA. Which of the following features would indicate that the molecule is RNA?

Accepted Answer

The presence of the base uracil and a ribose sugar.

Question 14

Which of the following best explains the importance of buffers in biological systems?

Accepted Answer

Buffers help maintain a stable pH by neutralizing excess acids or bases.

Question 15

Which of the following is a correct statement about the structure of proteins?

Accepted Answer

Proteins are polymers made of amino acids linked by peptide bonds.

Question 16

Which of the following best describes the difference between hydrolysis and dehydration synthesis?

Accepted Answer

Hydrolysis breaks polymers into monomers by adding water, while dehydration synthesis joins monomers by removing water.

Question 17

Which of the following best explains why phospholipids are important components of cell membranes?

Accepted Answer

They have hydrophilic heads and hydrophobic tails, allowing them to form bilayers that separate the cell from its environment.

Question 18

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

Accepted Answer

Hydrogen bonds are weak attractions between a hydrogen atom and an electronegative atom such as oxygen or nitrogen.

Question 19

A researcher is studying the effect of pH on enzyme activity. She finds that the enzyme works best at pH 7, but its activity decreases at both lower and higher pH values. What is the most likely explanation for this observation?

Accepted Answer

Changes in pH can alter the enzyme's shape, reducing its ability to bind to substrates.

Question 20

Which of the following best describes the relationship between monomers and polymers?

Accepted Answer

Monomers are small molecules that join together to form larger polymers.

General Biology Study Guide: Foundations, Chemistry, and Macromolecules

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