Question 1

Photosynthesis by plants and certain microbes traps the energy in light and uses it to:

Accepted Answer

A) reduce glucose into carbon dioxide. 
B) synthesize ATP from ADP and inorganic phosphate. 
C) generate ATP from the oxidation of reduced inorganic compounds. 
D) none of the above 
A) reduce glucose into carbon dioxide. 
B) synthesize ATP from ADP and inorganic phosphate. 
C) generate ATP from the oxidation of reduced inorganic compounds. 
D) none of the above

Question 2

NAD⁺ and FAD are often referred to as:

Accepted Answer

A) redox proteins. 
B) polymers. 
C) reduced dinucleotides. 
D) electron-carrying coenzymes. 
A) redox proteins. 
B) polymers. 
C) reduced dinucleotides. 
D) electron-carrying coenzymes.

Question 3

Which of the following is/are a hydrophilic amino acid?

Accepted Answer

A) aspartate 
B) serine 
C) tryptophan 
D) aspartate and serine 
A) aspartate 
B) serine 
C) tryptophan 
D) aspartate and serine

Question 4

Based on what you know about hydrophobic interactions,which of the following is/are composed of a bilayer?

Accepted Answer

A) a cell's membrane 
B) spontaneously aggregated phospholipids surrounding an aqueous interior 
C) lipid vesicles that have budded off the cell's membrane 
D) all of the above 
A) a cell's membrane 
B) spontaneously aggregated phospholipids surrounding an aqueous interior 
C) lipid vesicles that have budded off the cell's membrane 
D) all of the above

Question 5

How do phospholipids interact with water molecules?

Accepted Answer

A) The polar heads interact with water;the nonpolar tails do not. 
B) Phospholipids don't interact with water because water is polar and lipids are nonpolar. 
C) The polar heads avoid water;the nonpolar tails attract water (because water is polar and opposites attract). 
D) Phospholipids dissolve in water. 
A) The polar heads interact with water;the nonpolar tails do not. 
B) Phospholipids don't interact with water because water is polar and lipids are nonpolar. 
C) The polar heads avoid water;the nonpolar tails attract water (because water is polar and opposites attract). 
D) Phospholipids dissolve in water.

Question 6

Covalent bonds between which of the following pairs of atoms are nonpolar?

Accepted Answer

A) C-C 
B) C-H 
C) O-H 
D) a and b 
A) C-C 
B) C-H 
C) O-H 
D) a and b

Question 7

Which of the following is the weakest 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

Question 8

A solution of 8 M urea is sometimes used in the isolation of protein molecules.When the solution is prepared by dissolving urea in water at room temperature,it becomes cold.How should the ΔG for this process change if you tried to dissolve urea in the cold room,rather than at room temperature?

Accepted Answer

Urea will be less soluble at cold temper

Question 9

If the equilibrium constant for the reaction A→ B is 0.5 and the initial concentration of A is 25 mM and of B is 12.5 mM,then the reaction:

Accepted Answer

A) will proceed in the direction it is written,producing a net increase in the concentration of B. 
B) will produce energy,which can be used to drive ATP synthesis. 
C) will proceed in the reverse direction,producing a net increase in the concentration of A. 
D) is at equilibrium. 
A) will proceed in the direction it is written,producing a net increase in the concentration of B. 
B) will produce energy,which can be used to drive ATP synthesis. 
C) will proceed in the reverse direction,producing a net increase in the concentration of A. 
D) is at equilibrium.

Question 10

What is [P]/[R] when ΔG =ΔG°´?

Accepted Answer

A) -1 
B) 0 
C) 1 
D) 2.3 
A) -1 
B) 0 
C) 1 
D) 2.3

Question 11

The pKₐ of the weak base NH₃ is 9.25.When present in lysosomes,a subcellular organelle-ammonia-is almost totally protonated.Which of the pH values listed below is most likely to be that of the lysosome lumen?

Accepted Answer

A) 1 
B) 5 
C) 8 
D) 14 
A) 1 
B) 5 
C) 8 
D) 14

Question 12

Which of the following is true about an observed change in free energy (ΔG)?

Accepted Answer

A) Free energy was created when the Big Bang occurred. 
B) It can be calculated from the total change in energy,temperature,and change in entropy. 
C) If a reaction's free energy is greater than zero,it is likely to happen spontaneously. 
D) Free energy is comparable to unusable energy. 
A) Free energy was created when the Big Bang occurred. 
B) It can be calculated from the total change in energy,temperature,and change in entropy. 
C) If a reaction's free energy is greater than zero,it is likely to happen spontaneously. 
D) Free energy is comparable to unusable energy.

Question 13

Which of the following is a negatively charged amino acid?

Accepted Answer

A) alanine 
B) aspartate 
C) glutamine 
D) histidine 
A) alanine 
B) aspartate 
C) glutamine 
D) histidine

Question 14

When two atoms differing in electronegativity are joined in a covalent bond,then the:

Accepted Answer

A) electrons are shared equally between the atoms. 
B) bond is nonpolar. 
C) resulting compound is devoid of any dipole moment. 
D) atom with the greater electronegativity attracts the bonded electrons more strongly. 
A) electrons are shared equally between the atoms. 
B) bond is nonpolar. 
C) resulting compound is devoid of any dipole moment. 
D) atom with the greater electronegativity attracts the bonded electrons more strongly.

Question 15

Triacylglycerol and cholesterol esters are nonpolar;in contrast,phospholipids are amphipathic molecules.Biomembranes are based on phospholipids rather than on triacylglycerols.Why?

Accepted Answer

Biomembranes are based on phospholipids

Question 16

Phosphoglucomutase converts glucose 1-phosphate,the product of the reaction catalyzed by glycogen phosphorylase,into glucose 6-phosphate.The Kₑq for this reaction is 19 under standard conditions.What is the ΔG°´ for the reaction?

Accepted Answer

−1.741 kcal/mol,ΔG°´

Question 17

How do cells maintain a relatively constant pH despite the fact that many metabolic processes produce acids?

Accepted Answer

All cells contain buffers such

Question 18

A 1-mL solution of 0.05 M H₂SO₄ is diluted to 100 mL at 25°C.What is the pH of the resulting solution?

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
A) 1 
B) 2 
C) 3 
D) 4

Question 19

Hydrolysis of ATP:

Accepted Answer

A) is endothermic. 
B) has a positive ΔG value. 
C) must be coupled to an energetically favorable reaction. 
D) none of the above 
A) is endothermic. 
B) has a positive ΔG value. 
C) must be coupled to an energetically favorable reaction. 
D) none of the above

Question 20

The interactions between two proteins such as an antibody and an antigen or a hormone and its receptor are quite strong despite the fact that these interactions consist of relatively weak noncovalent bonds.How can this be?

Accepted Answer

Two proteins can bind tightly because of

Exam 1: Chemical Foundations

Photosynthesis by plants and certain microbes traps the energy in light and uses it to:

NAD⁺ and FAD are often referred to as:

Which of the following is/are a hydrophilic amino acid?

Based on what you know about hydrophobic interactions,which of the following is/are composed of a bilayer?

How do phospholipids interact with water molecules?

Covalent bonds between which of the following pairs of atoms are nonpolar?

Which of the following is the weakest interaction?

A solution of 8 M urea is sometimes used in the isolation of protein molecules.When the solution is prepared by dissolving urea in water at room temperature,it becomes cold.How should the ΔG for this process change if you tried to dissolve urea in the cold room,rather than at room temperature?

If the equilibrium constant for the reaction A→ B is 0.5 and the initial concentration of A is 25 mM and of B is 12.5 mM,then the reaction:

What is [P]/[R] when ΔG =ΔG°´?

The pKₐ of the weak base NH₃ is 9.25.When present in lysosomes,a subcellular organelle-ammonia-is almost totally protonated.Which of the pH values listed below is most likely to be that of the lysosome lumen?

Which of the following is true about an observed change in free energy (ΔG)?

Which of the following is a negatively charged amino acid?

When two atoms differing in electronegativity are joined in a covalent bond,then the:

Triacylglycerol and cholesterol esters are nonpolar;in contrast,phospholipids are amphipathic molecules.Biomembranes are based on phospholipids rather than on triacylglycerols.Why?

Phosphoglucomutase converts glucose 1-phosphate,the product of the reaction catalyzed by glycogen phosphorylase,into glucose 6-phosphate.The Kₑq for this reaction is 19 under standard conditions.What is the ΔG°´ for the reaction?

How do cells maintain a relatively constant pH despite the fact that many metabolic processes produce acids?

A 1-mL solution of 0.05 M H₂SO₄ is diluted to 100 mL at 25°C.What is the pH of the resulting solution?

Hydrolysis of ATP:

The interactions between two proteins such as an antibody and an antigen or a hormone and its receptor are quite strong despite the fact that these interactions consist of relatively weak noncovalent bonds.How can this be?

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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