Question 1

Why do sugars tend to be highly water soluble?

Accepted Answer

A) because they have only a few hydroxyl groups 
B) because of their large numbers of hydroxyl groups 
C) because of their large numbers of sulfhydryl groups 
D) because of their large numbers of methyl groups 
E) because of their small molecular weights 
A) because they have only a few hydroxyl groups 
B) because of their large numbers of hydroxyl groups 
C) because of their large numbers of sulfhydryl groups 
D) because of their large numbers of methyl groups 
E) because of their small molecular weights B

Question 2

How was it proved that the brains of patients suffering from CJD,an inherited disease,contain an infectious agent?

Accepted Answer

Carlton Gajdusek prepared extracts from a biopsy of the brain of a CJD victim.The extract was injected into a suitable laboratory animal.The animal developed a spongiform encephalopathy similar to that of kuru or CJD.

Question 3

A molecule that is capable of releasing or donating a hydrogen ion is termed a(n)_______.

Accepted Answer

A) base 
B) hydrion 
C) acid 
D) anachronism 
E) pain 
A) base 
B) hydrion 
C) acid 
D) anachronism 
E) pain C

Question 4

Which of the following tripeptides would be most likely to be soluble in an organic (hydrophobic)solvent like benzene: N - phenylalanine - alanine - glutamine - C,N - leucine - alanine - lysine - C,N - proline - phenylalanine - leucine - C,N - arginine - lysine - proline - C,N - glutamate - aspartate - glycine - C? Explain your answer.

Accepted Answer

N - proline - phenylalanine - leucine -

Question 5

Why are free radicals capable of altering molecules,such as proteins,nucleic acids and lipids?

Accepted Answer

They are extremely reactive,which makes

Question 6

Proteins are often composed of two or more distinct modules that fold up independently of one another.They often represent parts of a protein that function in a semi-independent manner.These modules are called ______.

Accepted Answer

A) protein motifs 
B) functionals 
C) domains 
D) dominoes 
A) protein motifs 
B) functionals 
C) domains 
D) dominoes

Question 7

Which interaction is most important in enhancing the solubility of macromolecules in water?

Accepted Answer

A) hydrophobic interactions 
B) nonpolar covalent bonds 
C) H bonds 
D) van der Waals forces 
E) Both hydrophobic interactions and nonpolar covalent bonds 
A) hydrophobic interactions 
B) nonpolar covalent bonds 
C) H bonds 
D) van der Waals forces 
E) Both hydrophobic interactions and nonpolar covalent bonds

Question 8

The most stable atoms and thus those that are typically nonreactive are the atoms that have _______.

Accepted Answer

A) equal numbers of electrons and protons 
B) equal numbers of electrons and neutrons 
C) full inner shells 
D) full outer shells 
E) all covalent bonds 
A) equal numbers of electrons and protons 
B) equal numbers of electrons and neutrons 
C) full inner shells 
D) full outer shells 
E) all covalent bonds

Question 9

What does the compound,2-phenylaminopyrimidine,inhibit? It was determined that 2-phenylaminopyrimidine would not have made a very effective drug.Why? What is the basis of Gleevec's effectiveness as a drug in the treatment of chronic myelogenous leukemia (CML)? Why do some patients taking Gleevec experience a recurrence of their cancer even though they initially went into remission?

Accepted Answer

It inhibits tyrosine kinases.It was a we

Question 10

You isolate superoxide dismutase from two cell culture lines.One of the lines (SOD1)has a level of SOD activity similar to that found in liver,the tissue from which the cell line was originally obtained.The other cell line (SOD10)has elevated SOD activity.The enzyme in SOD10 is extremely efficient at converting the superoxide free radical to hydrogen peroxide.In a routine check of other critical enzyme activities,catalase was found to have activity levels that were severely depressed in SOD10,while they appeared normal in SOD1.Observations of SOD10 reveal that this cell line cannot be maintained as easily as SOD1.SOD10 cells appear to die at an accelerated rate.What,if anything,can you conclude from these data?

Accepted Answer

While SOD10 is very efficient at neutral

Question 11

Which of the following tripeptides would be most likely to be soluble in an organic (hydrophobic)solvent like benzene?

Accepted Answer

A) N - phenylalanine - alanine - glycine - C 
B) N - leucine - alanine - lysine - C 
C) N - proline - phenylalanine - leucine - C 
D) N - arginine - lysine - proline - C 
E) N - glutamate - aspartate - glycine - C 
A) N - phenylalanine - alanine - glycine - C 
B) N - leucine - alanine - lysine - C 
C) N - proline - phenylalanine - leucine - C 
D) N - arginine - lysine - proline - C 
E) N - glutamate - aspartate - glycine - C

Question 12

You are working with an enzyme altase that you denature in the presence of urea.If altase were denatured no further by the addition of mercaptoethanol,what would that suggest to you about the enzyme?

Accepted Answer

The enzyme probably

Question 13

What type of protein secondary structure is characterized as being highly extensible because of its coiled structure?

Accepted Answer

A) $\beta$-pleated sheet 
B) double helix 
C)  $\alpha$-helix 
D) supercoiling 
A) $\beta$-pleated sheet 
B) double helix 
C)  $\alpha$-helix 
D) supercoiling

Question 14

Would all proteins be likely to require exposure to mercaptoethanol in order to accomplish full denaturation? If not,what trait would a protein that did not require mercaptoethanol possess?

Accepted Answer

Not all proteins would require

Question 15

What bond is responsible for the branch points in glycogen and amylopectin?

Accepted Answer

A) $\alpha$ (1->4)glycosidic linkages 
B) $\beta$ (1->4)glycosidic linkages 
C) $\alpha$(1->6)glycosidic linkages 
D) $\beta$(1->6)glycosidic linkages 
E) 3'-5' phosphodiester linkages 
A) $\alpha$ (1->4)glycosidic linkages 
B) $\beta$ (1->4)glycosidic linkages 
C) $\alpha$(1->6)glycosidic linkages 
D) $\beta$(1->6)glycosidic linkages 
E) 3'-5' phosphodiester linkages

Question 16

Mammals lack the enzyme that hydrolyzes cellulose.Yet many mammals are herbivores and they eat grass and other plant material for nutrition.How can this be,given that they cannot digest the food they are eating?

Accepted Answer

While these animals lack the enzyme that

Question 17

Why is silicon not suitable for making covalent bonds stable and strong enough to form the basis of living organisms,even though it is just below carbon on the periodic table?

Accepted Answer

A) Silicon is too large for its nucleus to attract the valence electrons of neighboring atoms enough to hold molecules together sufficiently. 
B) Silicon is too small for its nucleus to attract the valence electrons of neighboring atoms enough to hold molecules together sufficiently. 
C) Silicon is too large for its nucleus to attract the protons of neighboring atoms enough to hold molecules together. 
D) Silicon is too small for its nucleus to attract the protons of neighboring atoms enough to hold molecules together. 
A) Silicon is too large for its nucleus to attract the valence electrons of neighboring atoms enough to hold molecules together sufficiently. 
B) Silicon is too small for its nucleus to attract the valence electrons of neighboring atoms enough to hold molecules together sufficiently. 
C) Silicon is too large for its nucleus to attract the protons of neighboring atoms enough to hold molecules together. 
D) Silicon is too small for its nucleus to attract the protons of neighboring atoms enough to hold molecules together.

Question 18

What level of structure in proteins is held together by intermolecular R group interactions?

Accepted Answer

A) primary structure 
B) secondary structure 
C) tertiary structure 
D) quaternary structure 
A) primary structure 
B) secondary structure 
C) tertiary structure 
D) quaternary structure

Question 19

Red wine supposedly has health-related benefits.What antioxidant chemical is reputed to be responsible for these benefits? Where is this chemical normally found that explains its ending up in red wine? How is this chemical thought to exert its antioxidant effects?

Accepted Answer

Resveratrol.Resveratrol is a polyphenoli

Question 20

Which of the following is a nucleotide?

Accepted Answer

A) phosphate + ribose 
B) adenine + deoxyribose 
C) sugar + nitrogenous base 
D) adenine + ribose + phosphate 
A) phosphate + ribose 
B) adenine + deoxyribose 
C) sugar + nitrogenous base 
D) adenine + ribose + phosphate

Why do sugars tend to be highly water soluble?

How was it proved that the brains of patients suffering from CJD,an inherited disease,contain an infectious agent?

A molecule that is capable of releasing or donating a hydrogen ion is termed a(n)_______.

Why are free radicals capable of altering molecules,such as proteins,nucleic acids and lipids?

Proteins are often composed of two or more distinct modules that fold up independently of one another.They often represent parts of a protein that function in a semi-independent manner.These modules are called ______.

Which interaction is most important in enhancing the solubility of macromolecules in water?

The most stable atoms and thus those that are typically nonreactive are the atoms that have _______.

Which of the following tripeptides would be most likely to be soluble in an organic (hydrophobic)solvent like benzene?

You are working with an enzyme altase that you denature in the presence of urea.If altase were denatured no further by the addition of mercaptoethanol,what would that suggest to you about the enzyme?

What type of protein secondary structure is characterized as being highly extensible because of its coiled structure?

Would all proteins be likely to require exposure to mercaptoethanol in order to accomplish full denaturation? If not,what trait would a protein that did not require mercaptoethanol possess?

What bond is responsible for the branch points in glycogen and amylopectin?

Mammals lack the enzyme that hydrolyzes cellulose.Yet many mammals are herbivores and they eat grass and other plant material for nutrition.How can this be,given that they cannot digest the food they are eating?

Why is silicon not suitable for making covalent bonds stable and strong enough to form the basis of living organisms,even though it is just below carbon on the periodic table?

What level of structure in proteins is held together by intermolecular R group interactions?

Red wine supposedly has health-related benefits.What antioxidant chemical is reputed to be responsible for these benefits? Where is this chemical normally found that explains its ending up in red wine? How is this chemical thought to exert its antioxidant effects?

Which of the following is a nucleotide?

Introduction to the Study of Cell and Molecular Biology

Bioenergetics,enzymes and Metabolism

The Structure and Function of the Plasma Membrane

Aerobic Respiration and the Mitochondrion

Photosynthesis and the Chloroplast

Interactions Between Cells and Their Environment

Cytoplasmic Membrane Systems: Structure, function, and Membrane Trafficking

The Cytoskeleton and Cell Motility

The Nature of the Gene and the Genome

Gene Expression: From Transcription to Translation

Control of Gene Expression

Dna Replication and Repair

Cellular Reproduction

Cell Signaling and Signal Transduction: Communication Between Cells

Cancer

The Immune Response

Techniques in Cell and Molecular Biology

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Exam 2: The Chemical Basis of Life

Why do sugars tend to be highly water soluble?

How was it proved that the brains of patients suffering from CJD,an inherited disease,contain an infectious agent?

A molecule that is capable of releasing or donating a hydrogen ion is termed a(n)_______.

Why are free radicals capable of altering molecules,such as proteins,nucleic acids and lipids?

Proteins are often composed of two or more distinct modules that fold up independently of one another.They often represent parts of a protein that function in a semi-independent manner.These modules are called ______.

Which interaction is most important in enhancing the solubility of macromolecules in water?

The most stable atoms and thus those that are typically nonreactive are the atoms that have _______.

Which of the following tripeptides would be most likely to be soluble in an organic (hydrophobic)solvent like benzene?

You are working with an enzyme altase that you denature in the presence of urea.If altase were denatured no further by the addition of mercaptoethanol,what would that suggest to you about the enzyme?

What type of protein secondary structure is characterized as being highly extensible because of its coiled structure?

Would all proteins be likely to require exposure to mercaptoethanol in order to accomplish full denaturation? If not,what trait would a protein that did not require mercaptoethanol possess?

What bond is responsible for the branch points in glycogen and amylopectin?

Mammals lack the enzyme that hydrolyzes cellulose.Yet many mammals are herbivores and they eat grass and other plant material for nutrition.How can this be,given that they cannot digest the food they are eating?

Why is silicon not suitable for making covalent bonds stable and strong enough to form the basis of living organisms,even though it is just below carbon on the periodic table?

What level of structure in proteins is held together by intermolecular R group interactions?

Red wine supposedly has health-related benefits.What antioxidant chemical is reputed to be responsible for these benefits? Where is this chemical normally found that explains its ending up in red wine? How is this chemical thought to exert its antioxidant effects?

Which of the following is a nucleotide?

Introduction to the Study of Cell and Molecular Biology

Bioenergetics,enzymes and Metabolism

The Structure and Function of the Plasma Membrane

Aerobic Respiration and the Mitochondrion

Photosynthesis and the Chloroplast

Interactions Between Cells and Their Environment

Cytoplasmic Membrane Systems: Structure, function, and Membrane Trafficking

The Cytoskeleton and Cell Motility

The Nature of the Gene and the Genome

Gene Expression: From Transcription to Translation

Control of Gene Expression

Dna Replication and Repair

Cellular Reproduction

Cell Signaling and Signal Transduction: Communication Between Cells

Cancer

The Immune Response

Techniques in Cell and Molecular Biology

Filters