Question 1

Sugars with six carbons are the only ones capable of forming a ring structure as shown in a Haworth projection.

Accepted Answer

A) True 
 B)False

Question 2

When Keq of a reaction = 1, then

Accepted Answer

A)  the forward reaction is faster than the reverse reaction. 
B)  the reverse reaction is faster than the forward reaction. 
C)  the forward and reverse reaction rate constants are equal. 
D)  more products are formed than reactants. 
E)  fewer products are formed than reactants. 
A)  the forward reaction is faster than the reverse reaction. 
B)  the reverse reaction is faster than the forward reaction. 
C)  the forward and reverse reaction rate constants are equal. 
D)  more products are formed than reactants. 
E)  fewer products are formed than reactants.

Question 3

Why is it important that the enzymes in lysosomes are more active at acidic pH than at neutral pH?

Accepted Answer

A)  Since lysosomes are primarily found in the stomach acid of mammals, their pH dependence allows for maximum efficiency for the digestion of foodstuffs. 
B)  It prevents their diffusion out of the lysosomes. 
C)  It maximizes the interaction with their substrates which are always bases. 
D)  It prevents them from accidentally degrading the macromolecules in the cytosol. 
E)  It allows for regulation of their uptake by the mitochondria. 
A)  Since lysosomes are primarily found in the stomach acid of mammals, their pH dependence allows for maximum efficiency for the digestion of foodstuffs. 
B)  It prevents their diffusion out of the lysosomes. 
C)  It maximizes the interaction with their substrates which are always bases. 
D)  It prevents them from accidentally degrading the macromolecules in the cytosol. 
E)  It allows for regulation of their uptake by the mitochondria.

Question 4

The tendency of a metabolic reaction to proceed is due to the free energy of both the reactants and products as well as the change in randomness of that reaction.

Accepted Answer

A) True 
 B)False

Question 5

Enzymes are not as efficient as most catalysts used in organic chemistry, since they must function at body temperature.

Accepted Answer

A) True 
 B)False

Question 6

Which cellular component carries out oxidation reactions, some of which produce hydrogen peroxide?

Accepted Answer

A)  peroxisomes 
B)  mitochondria 
C)  chloroplasts 
D)  lysosomes 
E)  vacuoles 
A)  peroxisomes 
B)  mitochondria 
C)  chloroplasts 
D)  lysosomes 
E)  vacuoles

Question 7

A phosphodiester linkage in DNA contains two phosphorous atoms.

Accepted Answer

A) True 
 B)False

Question 8

Biochemical reactions are more likely to proceed if the reaction has an increase in enthalpy
(△H and a decrease in entropy △S).

Accepted Answer

A) True 
 B)False

Question 9

The Haworth projection of the ring form of a monosaccharide always shows a flat plane with one edge projecting out of the page using thicker lines).

Accepted Answer

A) True 
 B)False

Question 10

Mr is the mass of a molecule relative to 1/12 the mass of an atom of the most common isotope of carbon.

Accepted Answer

A) True 
 B)False

Question 11

Chloroplasts are organelles found in plants, algae and some protists and are the site of photosynthesis.

Accepted Answer

A) True 
 B)False

Question 12

Crick referred to the flow of information from nucleic acid to protein as the Central Dogma.

Accepted Answer

A) True 
 B)False

Question 13

Diffusion is an adequate means of distributing nutrients in prokaryotic cytoplasm because they have more surface area than volume compared to most eukaryotes.

Accepted Answer

A) True 
 B)False

Question 14

Which statement about cellulose is false?

Accepted Answer

A)  It is the most abundant polysaccharide in nature. 
B)  Its monomers are joined by glycosidic bonds. 
C)  It is present in the stems of flowering plants. 
D)  The hydroxyl groups of neighboring cellulose molecules interact to form strong, insoluble fibers. 
E)  It is a branched polymer of glucose. 
A)  It is the most abundant polysaccharide in nature. 
B)  Its monomers are joined by glycosidic bonds. 
C)  It is present in the stems of flowering plants. 
D)  The hydroxyl groups of neighboring cellulose molecules interact to form strong, insoluble fibers. 
E)  It is a branched polymer of glucose.

Question 15

One Angstrom is equal to 1 × 10-10 meters.

Accepted Answer

A) True 
 B)False

Question 16

The absolute molecular mass of macromolecules is given in daltons, where 1 dalton = 1 atomic mass unit.

Accepted Answer

A) True 
 B)False

Question 17

The nuclear envelope is a membrane that surrounds the nucleus and is continuous with the endoplasmic reticulum.

Accepted Answer

A) True 
 B)False

Question 18

The chemical name for ATP is alanine triphosphate.

Accepted Answer

A) True 
 B)False

Question 19

The role of DNA as the genetic material was confirmed by transforming Streptococci in experiments performed several years after the famous Watson and Crick description of DNA structure.

Accepted Answer

A) True 
 B)False

Question 20

Prokaryotes are valuable tools for biochemists because

Accepted Answer

A)  E. coli is well-studied and typical of prokaryotes. 
B)  they contain as many genes as eukaryotic cells. 
C)  many of their chromosomes are sequenced. 
D)  they are not very diverse organisms. 
E)  All of the above 
A)  E. coli is well-studied and typical of prokaryotes. 
B)  they contain as many genes as eukaryotic cells. 
C)  many of their chromosomes are sequenced. 
D)  they are not very diverse organisms. 
E)  All of the above

Exam 1: Introduction to Biochemistry

Sugars with six carbons are the only ones capable of forming a ring structure as shown in a Haworth projection.

When Keq of a reaction = 1, then

Why is it important that the enzymes in lysosomes are more active at acidic pH than at neutral pH?

The tendency of a metabolic reaction to proceed is due to the free energy of both the reactants and products as well as the change in randomness of that reaction.

Enzymes are not as efficient as most catalysts used in organic chemistry, since they must function at body temperature.

Which cellular component carries out oxidation reactions, some of which produce hydrogen peroxide?

A phosphodiester linkage in DNA contains two phosphorous atoms.

Biochemical reactions are more likely to proceed if the reaction has an increase in enthalpy (△H and a decrease in entropy △S).

The Haworth projection of the ring form of a monosaccharide always shows a flat plane with one edge projecting out of the page using thicker lines).

Mr is the mass of a molecule relative to 1/12 the mass of an atom of the most common isotope of carbon.

Chloroplasts are organelles found in plants, algae and some protists and are the site of photosynthesis.

Crick referred to the flow of information from nucleic acid to protein as the Central Dogma.

Diffusion is an adequate means of distributing nutrients in prokaryotic cytoplasm because they have more surface area than volume compared to most eukaryotes.

Which statement about cellulose is false?

One Angstrom is equal to 1 × 10-10 meters.

The absolute molecular mass of macromolecules is given in daltons, where 1 dalton = 1 atomic mass unit.

The nuclear envelope is a membrane that surrounds the nucleus and is continuous with the endoplasmic reticulum.

The chemical name for ATP is alanine triphosphate.

The role of DNA as the genetic material was confirmed by transforming Streptococci in experiments performed several years after the famous Watson and Crick description of DNA structure.

Prokaryotes are valuable tools for biochemists because

Water

Amino Acids and the Primary Structures of Proteins

Proteins: Three-Dimensional Structure and Function

Properties of Enzymes

Mechanisms of Enzymes

Coenzymes and Vitamins

Carbohydrates

Lipids and Membranes

Introduction to Metabolism

Glycolysis

Gluconeogenesis, the Pentose Phosphate Pathway, and Glycogen Metabolism

The Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Lipid Metabolism

Amino Acid Metabolism

Nucleotide Metabolism

Nucleic Acids

Dna Replication, Repair, and Recombination

Transcription and Rna Processing

Protein Synthesis

Recombinant Dna Technology

Filters

When K_eqof a reaction = 1, then

M_ris the mass of a molecule relative to 1/12 the mass of an atom of the most common isotope of carbon.

One Angstrom is equal to 1 × 10^-¹⁰meters.