Question 1

Which of the following represents the backbone structure of a DNA polymer?

Accepted Answer

A) base-sugar (ribose) 
B) phosphate-sugar (deoxyribose) 
C) base-sugar (deoxyribose) 
D) phosphate-base 
E) phosphate-sugar (ribose) 
A) base-sugar (ribose) 
B) phosphate-sugar (deoxyribose) 
C) base-sugar (deoxyribose) 
D) phosphate-base 
E) phosphate-sugar (ribose) B

Question 2

Approximately how many base pairs make up the human genome?

Accepted Answer

A) 3 million 
B) 64 million 
C) 3 billion 
D) 10 billion 
E) It is still unknown. 
A) 3 million 
B) 64 million 
C) 3 billion 
D) 10 billion 
E) It is still unknown. C

Question 3

Xeroderma pigmentosum is a genetic disease of DNA repair that results in a high incidence of skin cancer.

Accepted Answer

A) True 
 B)False  True

Question 4

What directional flow of information is referred to as the "central dogma of molecular biology"?

Accepted Answer

A) DNA → RNA → protein 
B) RNA → DNA → protein 
C) protein → DNA → RNA 
D) protein → RNA → DNA 
E) RNA → protein → DNA 
A) DNA → RNA → protein 
B) RNA → DNA → protein 
C) protein → DNA → RNA 
D) protein → RNA → DNA 
E) RNA → protein → DNA

Question 5

A DNA strand has the partial sequence 5'-GACTGA-3'.What would be the sequence of its complementary strand?

Accepted Answer

A) 5'-AGUCAG-3' 
B) 3'-AGTCAG-5' 
C) 5'-CTGACT-3' 
D) 3'-CTGACT-5' 
E) 5'-CUGACU-3' 
A) 5'-AGUCAG-3' 
B) 3'-AGTCAG-5' 
C) 5'-CTGACT-3' 
D) 3'-CTGACT-5' 
E) 5'-CUGACU-3'

Question 6

What type of bond connects the phosphate group to the sugar in a nucleotide?

Accepted Answer

A) phosphoester bond 
B) phosphoether bond 
C) glycosidic bond 
D) hydrogen bond 
E) ionic bond 
A) phosphoester bond 
B) phosphoether bond 
C) glycosidic bond 
D) hydrogen bond 
E) ionic bond

Question 7

How many turns of the DNA double helix correspond to twenty base pairs?

Accepted Answer

A) one 
B) six 
C) ten 
D) two 
E) twenty 
A) one 
B) six 
C) ten 
D) two 
E) twenty

Question 8

RNA can hybridize both to DNA and to other RNA molecules.

Accepted Answer

A) True 
 B)False

Question 9

What key role does the bacterium Thermus aquaticus play in the polymerase chain reaction (PCR)?

Accepted Answer

A) It is the source of the four nucleotides needed in PCR. 
B) It serves as the platform on which PCR proceeds. 
C) It provides the heat-stable DNA polymerase used in PCR. 
D) It aids in winding the newly produced DNA molecule with proteins to form a chromosome. 
E) It acts as a buffer to maintain a constant pH in the PCR solution. 
A) It is the source of the four nucleotides needed in PCR. 
B) It serves as the platform on which PCR proceeds. 
C) It provides the heat-stable DNA polymerase used in PCR. 
D) It aids in winding the newly produced DNA molecule with proteins to form a chromosome. 
E) It acts as a buffer to maintain a constant pH in the PCR solution.

Question 10

The only important requirement for hybridization of DNA fragments is the presence of complementary nucleic acid sequences.

Accepted Answer

A) True 
 B)False

Question 11

Which enzyme catalyzes the transcription of DNA?

Accepted Answer

A) transfer RNA 
B) messenger RNA 
C) DNA ligase 
D) RNA polymerase 
E) DNA polymerase 
A) transfer RNA 
B) messenger RNA 
C) DNA ligase 
D) RNA polymerase 
E) DNA polymerase

Question 12

What is the function of the enzyme DNA polymerase in replication?

Accepted Answer

A) It unwinds the double helix of DNA and separates the two strands. 
B) It reads the sequence of nucleotides on the parental strand of DNA and catalyzes the polymerization of a complementary daughter DNA strand. 
C) It reads the codons on a DNA molecule and catalyzes the polymerization of a complementary mRNA strand. 
D) It connects the short Okazaki fragments formed in the lagging strand. 
E) It carries the amino acids that are necessary to form a new daughter strand. 
A) It unwinds the double helix of DNA and separates the two strands. 
B) It reads the sequence of nucleotides on the parental strand of DNA and catalyzes the polymerization of a complementary daughter DNA strand. 
C) It reads the codons on a DNA molecule and catalyzes the polymerization of a complementary mRNA strand. 
D) It connects the short Okazaki fragments formed in the lagging strand. 
E) It carries the amino acids that are necessary to form a new daughter strand.

Question 13

Where does protein synthesis occur inside the cell?

Accepted Answer

A) in the cell membrane 
B) at the ribosomes 
C) inside the mitochondria 
D) at the lysosomes 
E) in the nucleus 
A) in the cell membrane 
B) at the ribosomes 
C) inside the mitochondria 
D) at the lysosomes 
E) in the nucleus

Question 14

What type of mutation results in the loss of one or more nucleotides from a DNA sequence?

Accepted Answer

A) omission 
B) deletion 
C) point 
D) silent 
E) fragmental 
A) omission 
B) deletion 
C) point 
D) silent 
E) fragmental

Question 15

Hydrogen bonding plays an important role in all but one of the items below.Which one does NOT involve hydrogen bonding?

Accepted Answer

A) DNA replication 
B) DNA double helix 
C) DNA primary structure 
D) synthesis of mRNA from DNA 
E) codon/anticodon recognition 
A) DNA replication 
B) DNA double helix 
C) DNA primary structure 
D) synthesis of mRNA from DNA 
E) codon/anticodon recognition

Question 16

What is the term used to describe a mutation that does not alter the amino acid sequence of the protein encoded by a gene?

Accepted Answer

A) nonsense 
B) sensible 
C) point 
D) silent 
E) fragmental 
A) nonsense 
B) sensible 
C) point 
D) silent 
E) fragmental

Question 17

Which technique allows scientists to produce unlimited amounts of any gene of interest?

Accepted Answer

A) gel electrophoresis 
B) polymerase chain reaction 
C) southern blot hybridization 
D) thermo coupling 
E) the Ames test 
A) gel electrophoresis 
B) polymerase chain reaction 
C) southern blot hybridization 
D) thermo coupling 
E) the Ames test

Question 18

Which statement is FALSE concerning the RNA structure?

Accepted Answer

A) RNA is usually single-stranded. 
B) RNA contains ribose instead of deoxyribose. 
C) RNA has a phosphoester linkage connecting the sugar to the phosphate group. 
D) Thymine is not in RNA. 
E) RNA and DNA are approximately the same size. 
A) RNA is usually single-stranded. 
B) RNA contains ribose instead of deoxyribose. 
C) RNA has a phosphoester linkage connecting the sugar to the phosphate group. 
D) Thymine is not in RNA. 
E) RNA and DNA are approximately the same size.

Question 19

Which of the following correctly describes a chromosome?

Accepted Answer

A) The location inside the cell where protein synthesis occurs. 
B) A segment of a DNA molecule that codes for a specific protein. 
C) A complex of 46 DNA molecules wrapped tightly together in a bundle. 
D) A sequence of three nucleotides that code for a specific amino acid. 
E) A complex of proteins and a single DNA molecule wrapped tightly together in a bundle. 
A) The location inside the cell where protein synthesis occurs. 
B) A segment of a DNA molecule that codes for a specific protein. 
C) A complex of 46 DNA molecules wrapped tightly together in a bundle. 
D) A sequence of three nucleotides that code for a specific amino acid. 
E) A complex of proteins and a single DNA molecule wrapped tightly together in a bundle.

Question 20

The genetic code is said to be "degenerate".What does this term indicate about the genetic code?

Accepted Answer

A) Different triplet codons serve as code words for the same amino acid. 
B) The genetic code contains regions of nonprotein coding sequences. 
C) The genetic code can easily undergo mutations that can lead to illnesses such as cancer. 
D) The genetic code is repetitive,and is identical in all species. 
E) The genetic code must be rewritten several times before a functional protein is formed. 
A) Different triplet codons serve as code words for the same amino acid. 
B) The genetic code contains regions of nonprotein coding sequences. 
C) The genetic code can easily undergo mutations that can lead to illnesses such as cancer. 
D) The genetic code is repetitive,and is identical in all species. 
E) The genetic code must be rewritten several times before a functional protein is formed.

Exam 20: Introduction to Molecular Genetics

Which of the following represents the backbone structure of a DNA polymer?

Approximately how many base pairs make up the human genome?

Xeroderma pigmentosum is a genetic disease of DNA repair that results in a high incidence of skin cancer.

What directional flow of information is referred to as the "central dogma of molecular biology"?

A DNA strand has the partial sequence 5'-GACTGA-3'.What would be the sequence of its complementary strand?

What type of bond connects the phosphate group to the sugar in a nucleotide?

How many turns of the DNA double helix correspond to twenty base pairs?

RNA can hybridize both to DNA and to other RNA molecules.

What key role does the bacterium Thermus aquaticus play in the polymerase chain reaction (PCR)?

The only important requirement for hybridization of DNA fragments is the presence of complementary nucleic acid sequences.

Which enzyme catalyzes the transcription of DNA?

What is the function of the enzyme DNA polymerase in replication?

Where does protein synthesis occur inside the cell?

What type of mutation results in the loss of one or more nucleotides from a DNA sequence?

Hydrogen bonding plays an important role in all but one of the items below.Which one does NOT involve hydrogen bonding?

What is the term used to describe a mutation that does not alter the amino acid sequence of the protein encoded by a gene?

Which technique allows scientists to produce unlimited amounts of any gene of interest?

Which statement is FALSE concerning the RNA structure?

Which of the following correctly describes a chromosome?

The genetic code is said to be "degenerate".What does this term indicate about the genetic code?

Chemistry - Methods and Measurement

The Structure of the Atom and the Periodic Table

Structure and Properties of Ionic and Covalent Compounds

Calculations, chemical Changes, and the Chemical Equation

States of Matter: Gases, liquids, and Solids

Solutions

Energy,rate and Equilibrium

Acids and Bases

The Nucleus, radioactivity, and Nuclear Medicine

An Introduction to Organic Chemistry

The Unsaturated Hydrocarbons: Alkenes, alkynes, and Aromatics

Alcohols, phenols, thiols, and Ethers

Aldehydes and Ketones

Carboxylic Acids and Carboxylic Acid Derivatives

Amines and Amides

Carbohydrates

Lipids and Their Functions in Biochemical Systems

Protein Structure and Function

Enzymes

Carbohydrate Metabolism

Aerobic Respiration and Energy Production

Fatty Acid Metabolism

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