OLE MISS | Bisc 102 - Exam 3 - Chapter 07

If the DNA in a cell consists of 20% adenine, it will also have _____ thymine.

20%

If the DNA in a cell consists of 20% adenine, then it will also contain ___ guanine.

30%

Which of the following best describes the relationship between DNA, proteins, and RNA? A. DNA is transcribed into RNA, then RNA is translated into proteins. B. DNA is transcribed into proteins, then proteins are translated into RNA. C. DNA is translated into RNA, then RNA is transcribed into proteins. D. DNA is translated into proteins, then proteins are transcribed into RNA.

A. DNA is transcribed into RNA, then RNA is translated into proteins.

What role do hydrogen bonds play in the DNA molecule? A. Hydrogen bonds link complementary nitrogenous bases, thus keeping the two strands of DNA parallel to each other. B. Hydrogen bonds link the two strands of DNA end to end during transcription and translation. C. Hydrogen bonds link the two strands of DNA end to end during transcription only. D. Hydrogen bonds link the complementary deoxyribose sugars, thus maintaining a separation between the two DNA strands. E. No answer is correct.

A. Hydrogen bonds link complementary nitrogenous bases, thus keeping the two strands of DNA parallel to each other.

Using the genetic code, what is the sequence of amino acids represented by the codons AUGUCAACGUGA? A. Met, Ser, Thr, (Stop) B. Tyr, Ser, Cys, Thr C. Ser, Tyr, Leu, Val D. Met, Val, Asp, Met

A. Met, Ser, Thr, (Stop)

If one strand of DNA has the nitrogenous base sequence ATTCGACGCTA, then the complementary strand has the nitrogenous base sequence A. TAAGCTGCGAT. B. ATCGCAGCTTA. C. UAAGCUGCGAU. D. ATTCGACGCTA.

A. TAAGCTGCGAT.

What did scientists discover was the primary cause for genetically controlled language disorder connected to language ability in other species? A. The cause was one mutation in a single gene on one chromosome. B. The disorder was not inherited but related to diet. C. Affected family members were lacking vocal chords. D. The cause was multiple mutations in multiple genes on one chromosome. E. The cause was multiple mutations in multiple genes on many chromosomes.

A. The cause was one mutation in a single gene on one chromosome.

How does the spread of viruses differ between plants and animals? A. Viruses must penetrate through cell walls of plant cells and not animal cells. B. Viruses spread faster in plants than animals because of photosynthesis. C. Viruses do not spread to plants, only animals. D. Viruses spread more slowly in plants than animals because of photosynthesis. E. Viruses that affect plants are all DNA viruses.

A. Viruses must penetrate through cell walls of plant cells and not animal cells.

A layer of membrane attached to a virus is called A. an envelope . B. a protein coat. C. a chromosome. D. a plasmid. E. a nucleus.

A. an envelope

Most viruses infect... A. infect only a few closely related species. B. infect only animal cells. C. infect a wide variety of organisms. D. cannot infect living cells. E. infect only plant cells.

A. infect only a few closely related species.

Most antibiotics are not effective against viruses because they _____ and this does not affect the activity of viruses. A. inhibit synthesis of cell walls B. destroy DNA and RNA C. inhibit all protein synthesis D. target envelopes E. inhibit reverse transcriptase

A. inhibit synthesis of cell walls

What type of mutation occurred in the following? Normal allele GGAAUGAAACAGGAACCC Mutant allele GGAAUGAAAUCAGGAACCC A. insertion B. substitution C. deletion D. frameshift

A. insertion

HIV A. is a retrovirus. B. infects most mammals. C. can be killed with antibiotics. D. causes liver cancer. E. can be transmitted through the skin.

A. is a retrovirus.

Where is the majority of DNA located in a human cell? A. nucleus B. mitochondrion C. chloroplast D. ribosome

A. nucleus

The stage of viral replication in which the viral nucleic acid is released inside the cell is A. penetration. B. release. C. attachment. D. synthesis. E. assembly.

A. penetration.

The stage of viral replication in which the new viruses leave the host cell is A. release. B. attachment. C. penetration. D. synthesis. E. assembly.

A. release.

The enzyme that HIV uses to convert its RNA into DNA is A. reverse transcriptase. B. DNA polymerase. C. RNA polymerase. D. RNA integrase. E. translase.

A. reverse transcriptase.

What type of mutation occurred in the following? Normal allele GGAAUGAAACAGGAACCC Mutant allele GGAAUGAAACAGGUACCC A. substitution B. insertion C. deletion D. frameshift E. No answer is correct.

A. substitution

Oral infections with herpes simplex virus 1 can lie dormant in nerve cells for years, and when a patient becomes stressed the virus is released, forming cold sores on the lips. Why would the virus form a cold sore? A. to spread to a new host B. so that it can mutate and survive antibiotic treatment C. to become latent in the body D. to avoid the immune system E. to warn other people that the host is infected

A. to spread to a new host

Amanatin is a toxin found in the death cap mushroom, Amanita phalloides. It inhibits RNA polymerase, thus blocking A. transcription. B. translation. C. replication. D. cell division. E. RNA splicing.

A. transcription.

How many codons are in the mRNA sequence GGAAUGAAACAGGAACCC? A. 12 B. 6 C. 27 D. 9 E. 3

B. 6

Viruses are A. consist of only a single cell. B. are smaller than cells. C. consist of multiple cells. D. contain a nucleus. E. contain ribosomes.

B. are smaller than cells.

If you were sorting labels for a diagram about viral replication, and if you found a part of the diagram saying that "the stage of viral replication in which viral components are put together to form new viruses," you would look for a label referring to A. release. B. assembly . C. attachment. D. penetration. E. synthesis.

B. assembly.

The rungs of the DNA ladder are formed by base pairs

B. joined by hydrogen bonds.

HIV is a A. double-stranded DNA virus. B. single-stranded RNA virus. C. single-stranded DNA virus. D. double-stranded RNA virus. E. prion.

B. single-stranded RNA virus.

One key reason why viruses are not considered living organisms is A. viruses do not contain genetic information. B. viruses do not reproduce on their own. C. viruses are all smaller than the smallest known cells. D. viruses do not contain a nucleus. E. viruses can be frozen and still survive.

B. viruses do not reproduce on their own.

RNA differs from DNA in many ways, including A. DNA contains deoxyribose and RNA contains ribose. B. DNA contains thymine and RNA contains uracil instead of thymine. C. All answers are correct. D. DNA is double stranded and RNA is single stranded. E. RNA can catalyze some chemical reactions and DNA cannot.

C. All answers are correct.

The influenza virus contains an RNA genome. Why do scientists typically have to make a new vaccine for the flu every year? A. because our bodies develop resistance to the vaccine and it becomes less effective B. because the virus develops resistance to the vaccine C. because the virus can mutate into new strains D. because people change their habits each year and become susceptible to different strains of the virus E. because the common influenza virus can come from many species of animals including cats and dogs

C. because the virus can mutate into new strains

The genetic information in viruses is A. is found in the nucleus of the virus. B. is always DNA. C. is either DNA or RNA. D. is always RNA. E. can be replicated outside of a cell.

C. is either DNA or RNA.

Oral infections with herpes simplex virus 1 can lie dormant in nerve cells for years, and when a patient becomes stressed, the virus is released, forming cold sores on the lips. While lying dormant, the virus is in which of the following states? A. lytic B. symptomatic C. latent D. replicative E. infective

C. latent

The length of a DNA sequence is _____ than the mature mRNA transcribed from it, because A. shorter; it does not contain exons. B. equal; it was transcribed from the DNA sequence. C. longer; it does not contain introns. D. shorter; each codon of three bases encodes only one amino acid. E. longer; each codon of one amino acid encodes three bases.

C. longer; it does not contain introns.

An infectious protein is a A. virus. B. viroid. C. prion. D. virion. E. prophage.

C. prion.

The stage of viral replication in which the host cell produces viral nucleic acids and proteins is A. release. B. attachment. C. synthesis. D. penetration. E. assembly.

C. synthesis.

Since viruses have no active methods of entering plant cells, they must rely upon mechanical insults to plants for entry. What probably prevents viruses from easily entering plant cells? A. the cell wall on the virus B. the plasma membrane on the plant C. the cell wall on the plant D. the plasma membrane on the virus E. the protein coat on the virus

C. the cell wall on the plant

If E. coli bacterium are grown in the presence of lactose A. the repressor will bind the operator, thus allowing transcription of the lac operon genes. B. the repressor will not bind the operator, thus preventing transcription of the lac operon genes. C. the repressor will not bind the operator, thus allowing transcription of the lac operon genes. D. the repressor will bind the operator, thus preventing transcription of the lac operon genes. E. No answer is correct.

C. the repressor will not bind the operator, thus allowing transcription of the lac operon genes.

A highly wound circle of RNA without a protein coat is a A. virus. B. virion. C. viroid. D. prion. E. prophage.

C. viroid.

Using the genetic code, how many amino acids are encoded by the following sequence from the start codon and up to the stop codon? AUGCUUGACUAAGUCCCC A. 0 B. 1 C. 2 D. 3 E. 5 F. 6

D. 3

Mutations create new alleles that A. are beneficial to the organism's fitness. B. have no effect on the fitness of the organism. C. decrease the fitness of the organism. D. All answers are correct. E. increase diversity at a genetic locus.

D. All answers are correct.

If you were a vet examining a cat with an illness, and tests showed that a viral infection was causing the cat's cells to burst, you would say that the cat had A. a rare form of viral infection. B. a transgenic infection. C. a lysogenic infection. D. a lytic infection. E. a systematic infection.

D. a lytic infection.

Using the genetic code, predict what type of mutation has occurred in the hemoglobin sickle cell anemia allele. Normal allele GGAAUGAAACAGGAACCC Mutant allele GGAAUGAAACAGGUACCC A. a point mutation, Val to Glu B. a frame shift C. addition of a new stop codon D. a point mutation, Glu to Val

D. a point mutation, Glu to Val

The stage of viral replication in which the virus binds to a cell surface receptor is A. release . B. penetration. C. synthesis. D. attachment . E. assembly.

D. attachment

In studies of the genetic basis of language, FOXP2 sequences differed the most between mice and A. rhesus monkeys. B. gorillas. C. chimpanzees. D. humans. E. All answers are correct.

D. humans.

If E. coli bacteria are grown in the absence of lactose A. the repressor will not bind the operator, thus allowing transcription of the lac operon genes. B. the repressor will bind the operator, thus allowing transcription of the lac operon genes. C. the repressor will not bind the operator, thus preventing transcription of the lac operon genes. D. the repressor will bind the operator, thus preventing transcription of the lac operon genes. E. No answer is correct.

D. the repressor will bind the operator, thus preventing transcription of the lac operon genes.

DNA differs from RNA because, unlike RNA,

DNA contains thymine.

If genetic tests showed that a tomato plant had viral DNA integrated into its chromosomes without outward symptoms caused bthe virus, you could say that the tomato plant had A. a rare form of viral infection. B. a transgenic infection. C. a lytic infection. D. a systematic infection. E. a lysogenic infection.

E. a lysogenic infection.

The correct sequence of stages of viral replication is A. attachment—synthesis—penetration—assembly—release B. penetration—attachment—assembly—synthesis—release C. penetration—attachment—synthesis—release—assembly D. attachment—penetration—assembly—synthesis—release E. attachment—penetration—synthesis—assembly—release

E. attachment—penetration—synthesis—assembly—release

Which of the following diseases is caused by something other than viruses? A. the common cold and influenza B. smallpox and mononucleosis C. polio and rabies D. AIDS and warts E. diabetes

E. diabetes

The double helix of DNA is composed of building blocks called

E. nucleotides. DNA is a double helix of two hydrogen-bonded strands. Please see section 7.1 for more information.

Our most potent weapon in the fight against viruses is A. antibiotics . B. sulfa drugs. C. gene therapy. D. surgery. E. vaccinations.

E. vaccinations.

True / False In DNA, T binds to G.

FALSE

True / False if you were creating a system for protein synthesis in a test tube, for RNA you would only need tRNA and rRNA.

FALSE

True / False A gene is an RNA sequence that is transcribed to mRNA only.

FALSE

True / False If you found a living Neadertal, genetic analysis of FOXP2 would show maximal similarity to the homologous gene in mice.

FALSE

True / False If you were looking at an electron micrograph of an mRNA molecule being translated by many ribosomes at once, you would be looking at a picture from a prokaryote.

FALSE

True / False In DNA, A binds to C.

FALSE

True / False Many viruses are inhibited by antibiotics.

FALSE

True / False RNA processing involves covalently attaching a piece of RNA to a piece of DNA.

FALSE

True / False "Mad cow disease" is caused by a viroid.

False

True / False "Tomato bunchy top" is caused by a virus.

False

True / False The amino acid that starts every protein and that is encoded by ACG is methionine.

False

Why would it take more energy to separate DNA with the sequence GCGCGCGC and its complementary strand than the sequence ATATATAT and its complementary strand?

G and C base pairs form more hydrogen bonds between DNA strands

Only one of the two strands of DNA is transcribed because

RNA polymerase binds to the promoter, initiating transcription on only one strand of DNA.

The DNA sequence ATGCATGC will pair with which of the following DNA strands?

TACGTACG

True / False Although antibiotics do not kill viruses, they offer promise for destroying viroids and prions because of their actions on cell ribosomes and enzymes.

TRUE

True / False In the bacterium E. coli, a repressor protein binds to the operator region of the DNA in the absence of lactose, thus preventing the transcription of the genes of the lactose operon.

TRUE

True / False Plant cells may help the whole plant fight a virus by dying on purpose.

TRUE

True / False A cell can receive new genes from a virus and then produce a new set of proteins.

TRUE

True / False A drug that inhibited reverse transcriptase could be used to fight some viruses.

TRUE

True / False A gene is any DNA sequence that is transcribed to any type of RNA.

TRUE

True / False A poly A tail is added to the mature mRNA after transcription.

TRUE

True / False Antibiotic resistance enhances the reproductive success of bacteria that have it.

TRUE

True / False Cystic fibrosis may be caused by a protein that does not fold correctly.

TRUE

True / False In eukaryotes, transcription copies only one gene from one DNA strand of the chromosome.

TRUE

True / False Mutations cause incorrect sequencing of nucleic acids. Incorrect sequencing of DNA will result in new alleles, and it may lead to evolution. Incorrect sequencing of mRNA will result in a faulty protein, but it will not lead to evolution.

TRUE

True / False RNA processing involves splicing.

TRUE

True / False Changes in gene expression can be adaptive, helping organisms contribute more to the next generation.

True

True / False Mutations can be caused by errors in copying DNA.

True

True / False Mutations can be caused by radiation.

True

True / False Mutations can be caused by environmental chemicals.

True

The DNA sequence ATGCATGC will pair with which of the following RNA strands?

UACGUACG

A change in a cell's DNA sequence is

a mutation.

A DNA sequence that signals the start of a gene is

a promoter.

In DNA molecules, Adenine pairs with_____

adenine pairs with thymine. AT and GC base pairs are critical for the structure of DNA.

A three-base sequence (loop) in tRNA that is complementary to a three-base sequence in mRNA is

an anticodon.

A tRNA molecule is "bilingual" because it binds to

codons of mRNA and amino acids.

In DNA molecules, cytosine pairs with_____

cytosine pairs with guanine.

The step of translation in which amino acids are added to the growing polypeptide is

elongation.

If you were seeking to change your life to avoid mutations in your DNA, which would be least useful to avoid?

exposure to magnesium

The step of translation in which an mRNA, a small ribosomal subunit, and the initiator tRNA are aligned together is

initiation.

In eukaryotic cells, sequences of mRNA removed before translation are called

introns.

What type of RNA carries the information that specifies a protein?

messenger RNA

A group of genes, a promoter, and an operator that control transcription are called a(n)

operon.

In a "silent" mutation

the codon that mutates does not cause a change in the amino acid specified.

The "Central Dogma" of molecular biology described by Watson and Crick describes

the directional flow of genetic information in cells.

In a "frameshift" mutation

the mutation is caused by an addition or deletion of one or more nucleotides.

In the lac operon, the protein that binds to the operator to prevent transcription is

the repressor.

Initiation, elongation, and termination are the three main steps in

transcription and translation

What are proteins that initiate transcription in eukaryotes by recognizing sequences within the promoter region of a gene and attracting RNA polymerase?

transcription factors

What type of RNA carries amino acids to the ribosome?

transfer RNA

What process converts the mRNA "message" into a sequence of amino acids?

translation