Question 1

Which of the following is NOT one of the ways RNA differs from DNA?

Accepted Answer

A) Ribonucleotides have a hydroxyl group on the 2 carbon of their sugar subunit. 
B) Ribonucleotides can have enzymatic activity. 
C) Ribonucleotides contain a phosphate group. 
D) Ribonucleotides can contain the base uracil. 
A) Ribonucleotides have a hydroxyl group on the 2 carbon of their sugar subunit. 
B) Ribonucleotides can have enzymatic activity. 
C) Ribonucleotides contain a phosphate group. 
D) Ribonucleotides can contain the base uracil. C

Question 2

The amount of free energy released when bonds are broken during a reaction is higher when the molecule has more electronegative atoms.

Accepted Answer

A) True 
 B)False  False

Question 3

You discover that you suffer from a deficiency in the amino acid tryptophan.At the pharmacy,you find both d-tryptophan and l-tryptophan supplements.Which do you purchase? Why?

Accepted Answer

You should choose l-tryptophan.All amino acids can exist as one of two stereoisomers (d or l)because of asymmetry around the α carbon.Proteins consist of the l form of amino acids,and as these stereoisomers possess distinct biological properties and are not readily interconverted,you should choose the form that is normally utilized by cells.

Question 4

What produces the dipole of a water molecule?

Accepted Answer

The dipole of a water molecule is caused

Question 5

Which of the following is a monosaccharide?

Accepted Answer

A) fructose 
B) galactose 
C) glucose 
D) all of the above 
A) fructose 
B) galactose 
C) glucose 
D) all of the above

Question 6

Cysteine often plays an important role in stabilizing protein structure.Explain how this works.

Accepted Answer

Two adjacent sulfhydryl (SH)groups can o

Question 7

Adenosine is a:

Accepted Answer

A) component of RNA. 
B) nucleoside. 
C) pyrimidine. 
D) a and b 
A) component of RNA. 
B) nucleoside. 
C) pyrimidine. 
D) a and b

Question 8

Which of the following is the BEST explanation for why vegetable oil is a liquid at room temperature while animal fats are solid?

Accepted Answer

A) Vegetable oil has fewer double bonds than animal fats. 
B) Animal fats have no amphipathic character. 
C) Vegetable oil has longer fatty-acid tails than do animal fats. 
D) Vegetable oil has more double bonds than do animal fats. 
A) Vegetable oil has fewer double bonds than animal fats. 
B) Animal fats have no amphipathic character. 
C) Vegetable oil has longer fatty-acid tails than do animal fats. 
D) Vegetable oil has more double bonds than do animal fats.

Question 9

A 1-mL solution of 0.1 M NaOH is diluted to 1 L at 25°C.What is the pH of the resulting solution?

Accepted Answer

A) 1 
B) 7 
C) 10 
D) 13 
A) 1 
B) 7 
C) 10 
D) 13

Question 10

The ultimate source of chemical energy for all cells is:

Accepted Answer

A) electricity. 
B) heat. 
C) light. 
D) magnetism. 
A) electricity. 
B) heat. 
C) light. 
D) magnetism.

Question 11

In a biochemical reaction in which ΔH  0:

Accepted Answer

A) the reaction is spontaneous. 
B) the reaction is endothermic. 
C) the reaction is endergonic. 
D) ΔG is positive. 
A) the reaction is spontaneous. 
B) the reaction is endothermic. 
C) the reaction is endergonic. 
D) ΔG is positive.

Question 12

In the reaction NAD⁺ + H⁺ + 2e−→ NADH,NAD⁺ becomes:

Accepted Answer

A) dehydrated. 
B) hydrolyzed. 
C) oxidized. 
D) reduced. 
A) dehydrated. 
B) hydrolyzed. 
C) oxidized. 
D) reduced.

Question 13

Under what conditions is the ΔG for a reaction different from the ΔG°´?

Accepted Answer

ΔG°´ is the Gibbs free energy of a react

Question 14

A nucleotide can vary in _____.

Accepted Answer

A) the base 
B) the sugar 
C) the phosphate group 
D) the sugar and the base 
A) the base 
B) the sugar 
C) the phosphate group 
D) the sugar and the base

Question 15

What is the effect of an enzyme on the end equilibrium concentration of reactants and products?

Accepted Answer

An enzyme has no eff

Question 16

Which of the following is a noncovalent interaction?

Accepted Answer

A) hydrophobic effect 
B) ionic interactions 
C) van der Waals interactions 
D) all of the above 
A) hydrophobic effect 
B) ionic interactions 
C) van der Waals interactions 
D) all of the above

Question 17

A reaction with a positive ΔG value can be made energetically favorable by increasing the:

Accepted Answer

A) ΔG°´. 
B) starting concentration of products. 
C) starting concentration of reactants. 
D) The first two answers are correct. 
A) ΔG°´. 
B) starting concentration of products. 
C) starting concentration of reactants. 
D) The first two answers are correct.

Question 18

The enzyme alcohol dehydrogenase is capable of catalyzing the oxidation of a number of different substances,including ethanol,ethylene glycol,and methanol,to an aldehyde.The metabolic products of both ethylene glycol and methanol are highly toxic to humans.A standard medical treatment for prevention of ethylene glycol or methanol poisoning is the administration of a dose of ethanol.Why is this treatment effective?

Accepted Answer

The ethanol-like ethylene glycol and met

Question 19

What is the major structural difference between starch and cellulose?

Accepted Answer

A) the types of monosaccharide subunits in the molecules 
B) the amount of branching that occurs in the molecule 
C) that humans can only ingest starch 
D) the type of glycosidic linkages in the molecule 
A) the types of monosaccharide subunits in the molecules 
B) the amount of branching that occurs in the molecule 
C) that humans can only ingest starch 
D) the type of glycosidic linkages in the molecule

Question 20

Which of the following is the strongest interaction?

Accepted Answer

A) hydrogen bond 
B) ionic bond 
C) phosphoanhydride bond 
D) van der Waals interaction 
A) hydrogen bond 
B) ionic bond 
C) phosphoanhydride bond 
D) van der Waals interaction

Exam 1: Chemical Foundations

Which of the following is NOT one of the ways RNA differs from DNA?

The amount of free energy released when bonds are broken during a reaction is higher when the molecule has more electronegative atoms.

You discover that you suffer from a deficiency in the amino acid tryptophan.At the pharmacy,you find both d-tryptophan and l-tryptophan supplements.Which do you purchase? Why?

What produces the dipole of a water molecule?

Which of the following is a monosaccharide?

Cysteine often plays an important role in stabilizing protein structure.Explain how this works.

Adenosine is a:

Which of the following is the BEST explanation for why vegetable oil is a liquid at room temperature while animal fats are solid?

A 1-mL solution of 0.1 M NaOH is diluted to 1 L at 25°C.What is the pH of the resulting solution?

The ultimate source of chemical energy for all cells is:

In a biochemical reaction in which ΔH < 0 and ΔS > 0:

In the reaction NAD⁺ + H⁺ + 2e−→ NADH,NAD⁺ becomes:

Under what conditions is the ΔG for a reaction different from the ΔG°´?

A nucleotide can vary in _____.

What is the effect of an enzyme on the end equilibrium concentration of reactants and products?

Which of the following is a noncovalent interaction?

A reaction with a positive ΔG value can be made energetically favorable by increasing the:

What is the major structural difference between starch and cellulose?

Which of the following is the strongest interaction?

Molecular Genetic Techniques

Protein Structure and Function

Culturing and Visualizing Cells

Fundamental Molecular Genetic Mechanisms

Bio-membrane Structure

Genes Genomics and Chromosomes

Transcriptional Control of Gene Expression

Post-Transcriptional Gene Control

Transmembrane Transport of Ions and Small Molecules

Cellular Energetics

Moving Proteins Into Membranes and Organelles

Vesicular Traffic, Secretion, and Endocytosis

Signal Transduction and G-Protein Coupled Receptors

Signaling Pathways That Control Gene Activity

Cell Organization and Movement I: Microfilaments

Cell Organization and Movement II: Microtubules and Intermediate Filaments

Regulating the Eukaryotic Cell Cycle

Integrating Cells Into Tissues

Cell Birth, Lineage, and Death

Nerve Cells

Immunology

Cancer

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