Biology Exam 5 Mastering Biology Questions

Which of the above crosses would give us information about whether or not the two genes are linked? (ii) only both (ii) and (iii) both (i) and (ii) (iii) only (i) only

both (ii) and (iii)

_____ bind(s) to DNA enhancer regions. RNA polymerase Promoters Introns Activators Exons

Activators

The direction of synthesis of an RNA transcript is _____. 1' —> 5' 5' —> 3' 1' —> 3' 3' —> 5' 2' —> 4'

5' —> 3' (Nucleotides are added to the 3' end of RNA.)

Which of the following RNA molecules carries amino acids corresponding to specific codons? mRNA pre-mRNA rRNA tRNA none of these.

tRNA

For the following question, please use the following information: In humans, a recessive allele of a gene on the X chromosome causes humans to be "colorblind." A colorblind XY man and an XX woman whose genotype is homozygous for normal color vision have children together. What percentage of their offspring are expected be colorblind? Too little information given to choose an answer 0% 25% 50% 75%

0%

There are three principles to keep in mind when predicting the sequence of the mRNA produced by transcription of a particular DNA sequence.

1. The RNA polymerase reads the sequence of DNA bases from only one of the two strands of DNA: the template strand. 2. The RNA polymerase reads the code from the template strand in the 3' to 5' direction and thus produces the mRNA strand in the 5' to 3' direction. 3. In RNA, the base uracil (U) replaces the DNA base thymine (T). Thus the base-pairing rules in transcription are A→U, T→A, C→G, and G→C, where the first base is the coding base in the template strand of the DNA and the second base is the base that is added to the growing mRNA strand.

If alleles of the two genes assort independently, what is the predicted ratio of parental:recombinant types from cross (iii)? 3:1 4:0 2:2 0:4 1:3

2:2

The percentage of the adenine (A) nucleotide in a particular organism's genome is 30%. The percentages of the other nucleotides must be approximately 70% T, 0% G, 0% C 30% T, 20% G, 20% C 20% T, 30% G, 20% C not enough information given the question is nonsense; all nucleotides must account for 25%, due to complementarity in the double-stranded DNA molecule

30% T, 20% G, 20% C

Which of these binds to receptor molecules on the host cell membrane? The figure shows the structure of the retrovirus, HIV. Letters from A to E mark definite structures. Letter A marks the fungiform structures on the viral envelope. Letter B marks the envelope of the HIV. Letter C marks small spherical structure near viral genome. Letter D marks the envelope that surrounds the viral genome. Letter E marks spirally curved filamentous structures inside the viral particle. A B C D E

A (Glycoproteins on the viral envelope recognize and bind to receptors on the host cell)

Which of these indicates an enhancer region? The figure shows a diagram of genes work regulation. Letters from A to D mark the definite process. Letter A marks the parts of the gene, to which activators bind. Letter B marks the part of the gene, to which RNA-polymerase is attached. Letter C marks the enzyme, which moves along the transcription. Letter D marks the proteins that bind to the specific part of the gene at the beginning of the transcription. A B C D C and D

A (This is an enhancer region)

Which of these regions is most likely to develop into the Drosophilia's head? A B C D E

A (This is the region with the highest concentration of bicoid protein)

Check ALL of the following that are possible consequences of reassortment in viruses. Reassortment can be used by researchers in the lab to produce "live attenuated" vaccines. Reassortment can lead to the evolution of new strains of influenza. Reassortment can recombine genetic elements from different influenza strains.

All

Mark ALL answers that apply. Even single-celled organisms like bacteria need to regulate expression of their genes because some genes in a bacterium's genome may have opposing functions. Not all functions of all genes are needed at one time. They live in variable environments.

All

What would you expect to see involved in transcription of a gene in eukaryotes but NOT in bacteria? a promoter a combination of about 10 transcription factors RNA polymerase RNA nucleotides a DNA template

A combination of about 10 transcription factors

Which statements about viruses are true? Select the four statements that are true. A retrovirus contains RNA. All RNA-containing viruses are retroviruses. All viral genomes contain both DNA and RNA. The capsid enters the host cell if the virus is enveloped. Enveloped viruses bud from the host cell. HIV contains reverse transcriptase. HIV contains two identical strands of DNA.

A retrovirus contains RNA. The capsid enters the host cell if the virus is enveloped. Enveloped viruses bud from the host cell. HIV contains reverse transcriptase.

Part complete Consider a study of two genes, "A" and "B". Each gene has two alleles, represented by upper- and lower-case letters. Assume that an upper-case letter represents a dominant allele, and a lower-case letter represents a recessive allele. If the parental cross ("P" generation) is AABB x aabb, which the following crosses would represent an F1 testcross? aabb x aabb AABB x AaBb AABB x aabb AaBb x aabb AaBb x AaBb

AaBb x aabb

The region of a Drosophila embryo with a low concentration of bicoid protein will develop into the _____. abdomen male flowers thorax head female flowers

Abdomen (The abdomen develops where there is a low concentration of bicoid protein)

Part complete Transcription begins at a promoter. What is a promoter? A site found on the RNA polymerase The same as a start codon A site in DNA that recruits the RNA Polymerase Part of the RNA molecule itself

A site in DNA that recruits the RNA Polymerase (This is the site where the RNA polymerase must bind to initiate transcription.)

Transcription begins at a promoter. What is a promoter? A site found on the RNA polymerase The same as a start codon A site in DNA that recruits the RNA Polymerase Part of the RNA molecule itself

A site in DNA that recruits the RNA polymerase (This is the site where the RNA polymerase must bind to initiate transcription.)

Which of the following mutations is most likely to affect the protein coded for by a eukaryotic gene? A substitution mutation in the first position of one of the gene's codons A substitution mutation in the gene's promoter A substitution mutation in the third position of one of the gene's codons A substitution mutation in the gene's enhancer A substitution mutation in one of the gene's introns

A substitution mutation in the first position of one of the gene's codons

Differential gene expression can be established and maintained in an organism by cytoplasmic determinants that are distributed unevenly in the unfertilized egg. inductive signals from one cell to another. gradients of molecules in developing tissues. the products of regulatory genes. all of these.

All of these

Genes that are organized in an operon Are served by one promoter. Can all be turned on or off at the same time. Encode proteins with complementary functions. Are transcribed in one large mRNA. All of these answers are correct.

All of these answers are correct.

A consequence of reassortment in viruses like influenza could be that a new strain of influenza evolves. genes from different virus strains are combined in a single virus. last year's influenza vaccine is not effective against this year's most common strain. a new influenza strain has the ability to "jump" hosts from pigs to humans. all of these answers.

All of these answers.

During DNA replication Each strand can act as a template for the replication of the molecule The two strands of the original DNA molecule must be separated Enzymes facilitate all the steps involved Each of the original two strands of DNA will wind up in a different chromatid All of these are correct

All of these are correct

In most of your body's cells, the loss of DNA from both ends (telomeres) of chromosomes after many rounds of replication is due to the fact that DNA polymerase only synthesizes new strands from 5' to 3'. DNA polymerase can only build onto the end of an existing nucleic acid strand. The two strands of a DNA double helix are antiparallel to one another. Enzymes that can rebuild telomeres are not active in most of your cells. All of these are valid reasons.

All of these are valid reasons.

Polypeptides are assembled from _____. hexoses glycerol nucleotides proteins amino acids

Amino Acids (Proteins are composed of amino acid monomers)

Which of the following mutations is most likely to create a frameshift mutation in a eukaryotic gene? A deletion of 6 nucleotides in one of the gene's exons An insertion of 3 nucleotides in one of the gene's exons An insertion of 1 nucleotide in one of the gene's exons. A substitution mutation in one of the gene's exons A substitution mutation in one of the gene's introns

An insertion of 1 nucleotide in one of the gene's exons.

Which of these is a tRNA? A B C D E

B

Coordinate control (turning multiple genes with related functions on or off at the same time) is important in Bacteria only. Bacteria and eukaryotes. Eukaryotes only. No organisms. Animals but not plants or bacteria.

Bacteria and Eukaryotes

What determines which base is to be added to an RNA strand during transcription? The previous base Base pairing between the two DNA strands The order of the chemical groups in the backbone of the RNA molecule Base pairing between the DNA template strand and the RNA nucleotides

Base pairing between the DNA template strand and the RNA nucleotides (Transcription involves the formation of an RNA strand that is complementary to the DNA template strand.)

Which of these is reverse transcriptase? The figure shows the structure of the retrovirus, HIV. Letters from A to E mark definite structures. Letter A marks the fungiform structures on the viral envelope. Letter B marks the envelope of the HIV. Letter C marks small spherical structure near viral genome. Letter D marks the envelope that surrounds the viral genome. Letter E marks spirally curved filamentous structures inside the viral particle. A B C D E

C

Which of these directly bind(s) to the promoter? The figure shows a diagram of genes work regulation. Letters from A to D mark the definite process. Letter A marks the parts of the gene, to which activators bind. Letter B marks the part of the gene, to which RNA-polymerase is attached. Letter C marks the enzyme, which moves along the transcription. Letter D marks the proteins that bind to the specific part of the gene at the beginning of the transcription. A B C D C and D

C and D (Both RNA polymerase and transcription factors bind with the promoter)

The tRNA anticodon, GAC, is complementary to the mRNA codon with the sequence _____. CAG CTG GAC CUG TCG

CUG

Part complete Which of the following terms best describes the relationship between the newly synthesized RNA molecule and the DNA template strand? Identical Complementary Covalently bound Permanently base-paired

Complementary (Because the template strand determines the nucleotides to be added to the RNA strand, using the same complementarity rules of the DNA, they will be complementary to each other.)

The physical process that makes gene linkage incomplete is segregation mitosis the lining up of chromosomes in the middle of the cell cyclin reaching a threshold concentration crossing over

Crossing Over

In the diagram below, the two blue strands represent _____. The figure shows a blue molecule arranged in the form of a double chain. The gray unit on this figure represents an oval structure which contains unwound and unpaired chains of this molecule. Before and after this unit, the molecule is wound in the form of a double helix. A green unit represents a part of the double helix before the gray unit. View Available Hint(s) RNA DNA transcription factors RNA polymerase the promoter

DNA (DNA is a double helix)

Check ALL of the following that give examples of how viral gene expression can defy the "central dogma" of biology. DNA is made from an RNA template mRNA is made from an RNA template mRNA is made from a DNA template

DNA is made from an RNA template mRNA is made from an RNA template

Why is the new DNA strand complementary to the 3' to 5' strands assembled in short segments? only short DNA sequences can extend off the RNA primers DNA polymerase can assemble DNA only in the 5' to 3' direction DNA polymerase can assemble DNA only in the 3' to 5' direction it is more efficient than assembling complete new strands the replication forks block the formation of longer strands

DNA polymerase can assemble DNA only in the 5' to 3' direction (Since DNA polymerase can assemble DNA only in the 5' to 3' direction, the new strand complementary to the 3' to 5' strand must be assembled either in short 5' to 3' segments, which are later joined together by ligase, or be assembled continuously)

Part complete Which of the following is the earliest time when molecules are put in place that can set up major body axes? After many cell divisions Just after fertilization After the first cell division of the zygote During formation of the egg (before fertilization) Once the organism has a recognizable adult shape

During the formation of the egg (before fertilization)

Which of these is the viral genome? The figure shows the structure of the retrovirus, HIV. Letters from A to E mark definite structures. Letter A marks the fungiform structures on the viral envelope. Letter B marks the envelope of the HIV. Letter C marks small spherical structure near viral genome. Letter D marks the envelope that surrounds the viral genome. Letter E marks spirally curved filamentous structures inside the viral particle. A B C D E

E (HIV is an RNA virus)

DNA replication is said to be semiconservative. What does this mean? One strand of the new double helix is made of DNA, and the other strand is made of RNA. Half of the old strand is degraded, and half is used as a template for the replication of a new strand. One of the two resulting double helices is made of two old strands, and the other is made of two new strands. The old double helix is degraded, and half of its nucleotides are used in the construction of two new double helices. Each new double helix consists of one old and one new strand.

Each new double helix consists of one old and one new strand. (Each new double helix consists of one old and one new strand; This is the meaning of the term "semiconservative.")

Operons in bacteria and master regulatory genes in eukaryotes are similar in that both Are always turned on by default. Enable an organism to turn on multiple genes simultaneously. Are turned on by activator proteins bound to enhancers. Produce proteins that are transcription factors. Consist of multiple genes located next to one another on the same chromosome.

Enable an organism to turn on multiple genes simultaneously

The RNA segments joined to one another by spliceosomes are _____. caps exons snRNPs tails introns

Exons (Exons are expressed regions)

Expression of a liver gene requires a transcription factor that is also required for expression of an eye gene. If liver cells and eye cells have the same transcription factor, why isn't the liver gene expressed in your eye cells? Expression of each gene requires a unique combination of multiple transcription factors. Your brain "tells" your eye cells not to make liver proteins. Your liver cells "tell" your eye cells not to make liver proteins. The liver operon is turned off in your eyes. Genes for liver proteins are missing from the genomes of the cells of your eyes.

Expression of each gene requires a unique combination of multiple transcription factors.

The pointer is indicating the virus's _____. The figure shows a particle, which consists of two wavy strands, pointed by the arrow and with an envelope around it. envelope genome mitochondria capsid microfilaments

Genome (The pointer is indicating the virus's nucleic acid genome)

Which of these correctly illustrates the pairing of DNA and RNA nucleotides? GTTACG CAATCG GTTACG CAAUGC GTTACG GTTACG GTTACG ACCGTA GTTACG UAACAU

GTTACG CAAUGC (In RNA, uracil takes the place of thymine.)

The first step in the replication of DNA is catalyzed by _____. ligase single-strand binding protein DNA polymerase primase helicase

Helicase

What holds the two strands of a DNA molecule together? Ionic bonds between negatively and positively charged ions Covalent bonds between sugars and phosphates Brüno's interactions Hydrogen bonds between complementary base pairs

Hydrogen bonds between complementary base pairs

What is the name of the process shown in the diagram? initiation (of transcription) RNA processing initiation (of translation) elongation termination (of translation)

Initiation (of translation)

What is the function of reverse transcriptase? It catalyzes the formation of a polypeptide from an RNA template. It catalyzes the formation of DNA from a polypeptide template. It catalyzes the formation of RNA from a polypeptide template. It catalyzes the formation of RNA from a DNA template. It catalyzes the formation of DNA from an RNA template.

It catalyzes the formation of DNA from an RNA template. (This is the function of reverse transcriptase)

What happens to RNA polymerase II after it has completed transcription of a gene? It is degraded. It is free to bind to another promoter and begin transcription. It joins with another RNA polymerase to carry out transcription. It begins transcribing the next gene on the chromosome.

It is free to bind to another promoter and begin transcription. (The enzyme is free to transcribe other genes in the cell.)

Males are more often affected by sex-linked traits than females because males usually have a single copy of the X chromosome. X chromosomes in males generally have more mutations than X chromosomes in females. male hormones such as testosterone often alter the effects of mutations on the X chromosome. female hormones such as estrogen often compensate for the effects of mutations on the X chromosome. mutations on the Y chromosome often worsen the effects of X-linked mutations.

Males usually have a single copy of the X chromosome.

After transcription begins, several steps must be completed before the fully processed mRNA is ready to be used as a template for protein synthesis on the ribosomes. Which three statements correctly describe the processing that takes place before a mature mRNA exits the nucleus? A translation stop codon is added at the 3' end of the pre-mRNA. Coding sequences called exons are spliced out by ribosomes. Noncoding sequences called introns are spliced out by molecular complexes called spliceosomes. A poly-A tail (50-250 adenine nucleotides) is added to the 3' end of the pre-mRNA. A cap consisting of a modified guanine nucleotide is added to the 5' end of the pre-mRNA.

Noncoding sequences called introns are spliced out by molecular complexes called spliceosomes. A poly-A tail (50-250 adenine nucleotides) is added to the 3' end of the pre-mRNA. A cap consisting of a modified guanine nucleotide is added to the 5' end of the pre-mRNA. (Once RNA polymerase II is bound to the promoter region of a gene, transcription of the template strand begins. As transcription proceeds, three key steps occur on the RNA transcript: Early in transcription, when the growing transcript is about 20 to 40 nucleotides long, a modified guanine nucleotide is added to the 5' end of the transcript, creating a 5' cap. Introns are spliced out of the RNA transcript by spliceosomes, and the exons are joined together, producing a continuous coding region. A poly-A tail (between 50 and 250 adenine nucleotides) is added to the 3' end of the RNA transcript. Only after all these steps have taken place is the mRNA complete and capable of exiting the nucleus. Once in the cytoplasm, the mRNA can participate in translation.)

If an important cytoplasmic determinant were missing from an animal zygote, what would you expect to happen as the zygote developed into a multicellular organism? The animal would lack certain amino acids. The animal would lack ribosomes. DNA polymerase would be unable to replicate the animal's genome. The animal would develop normally. One of the animal's major body axes would fail to develop normally.

One of the animal's major body axes would fail to develop normally.

In DNA replication, the main difference between the "leading strand" and the "lagging strand" is that Only the lagging strand is synthesized as a series of short fragments. Only the leading strand is made of DNA. Only the lagging strand starts with a primer. Only the leading strand contains genes. Replication of the leading strand is completed before replication of the lagging strand begins.

Only the lagging strand is synthesized as a series of short fragments.

Which of the following lists the steps involved in DNA replication in the correct order? Open DNA double helix → RNA primer synthesized → mRNA synthesized → RNA replaced with DNA Open DNA double helix → RNA primer synthesized → DNA synthesized → RNA primers replaced with DNA Open DNA double helix → DNA primer synthesized → mRNA synthesized Assemble the ribosome → scan mRNA for start codon → make DNA copy from mRNA Transcription factors bind to promoter → RNA polymerase copies all the genes

Open DNA double helix → RNA primer synthesized → DNA synthesized → RNA primers replaced with DNA

DNA does not store the information to synthesize which of the following? DNA Organelles Messenger RNA Proteins

Organelles (Synthesis of organelles is not directly coded in the DNA.)

DNA replication in your cells begins at one end of a chromosome. start codons. origins of replication. stop codons. promoters.

Origins of replication

Pax-6 is a gene that is involved in eye formation in many invertebrates, such as Drosophila. Pax-6 is found as well in vertebrates. A Pax-6 gene from a mouse can be expressed in a fly and the protein (PAX-6) leads to a compound fly eye. This information suggests which of the following? PAX-6 from a mouse can function in a fly, but a fly's Pax-6 gene cannot function in a mouse. Pax-6 genes are identical in nucleotide sequence. PAX-6 proteins are different for formation of different kinds of eyes. Pax-6 is highly conserved and shows shared evolutionary ancestry. PAX-6 proteins have identical amino acid sequences.

Pax-6 is highly conserved and shows shared evolutionary ancestry.

What name is given to the process in which pre-mRNA is edited into mRNA? RNA processing gene expression polypeptide formation transcription translation

RNA Processing (RNA processing edits the RNA transcript that has been assembled along a DNA template)

Part complete Which of the following are involved in the initiation of transcription in eukaryotes? Origin of replication, RNA primers, enzymes Promoter, transcription factors, RNA polymerase Telomere, stop codon Start codon, ribosome, mRNA, tRNA Operator, operon, repressor

Promoter, transcription factors, RNA polymerase

Double-stranded viral DNA is incorporated into a host cell as a _____. promoter provirus transposon lac homeoboxes

Provirus ("Provirus" is the name given to double-stranded viral DNA that has been incorporated into a host cell's genome)

In the diagram below, the gray unit represents _____. The figure shows a blue molecule arranged in the form of a double chain. The gray unit on this figure represents an oval structure which contains unwound and unpaired chains of this molecule. Before and after this unit, the molecule is wound in the form of a double helix. A green unit represents a part of the double helix before the gray unit. RNA DNA transcription factors RNA polymerase the promoter

RNA polymerase (RNA polymerase untwists a portion of the DNA double helix.)

The synthesis of a new strand begins with the synthesis of a(n) _____. RNA primer complementary to a preexisting DNA strand poly(A) tail short pieces of DNA Okazaki fragment single-strand binding protein

RNA primer complementary to a preexisting DNA strand (The synthesis of a DNA strand begins with the formation of an RNA primer)

The action of helicase creates _____. DNA fragments and replication bubbles primers and replication bubbles replication forks and replication bubbles DNA fragments and replication forks primers and DNA fragments

Replication forks and replication bubbles (A replication fork is the transition region between paired and unpaired DNA strands.)

Click on the diagram to start the animation. What enzyme is responsible for the process seen here? RNA polymerase DNA polymerase reverse transcriptase endonuclease DNA ligase

Reverse transcriptase (Reverse transcriptase catalyzes the formation of DNA from an RNA template)

For the following question, please use the following information: In humans, a recessive allele of a gene on the X chromosome causes humans to be "colorblind." In the following question, " c " is the recessive allele that causes colorblindness, " c+ " is the dominant allele for normal color vision, and " Y " is the human Y chromosome. Your professor (Sam) and his wife (Becca) both have normal color vision, but their son is colorblind. What do you know about Sam's and Becca's genotypes? Sam = c+ c+, Becca = c+ c+ Sam = c+ c, Becca = c+ c Sam = c Y, Becca = c c Sam = c+ Y, Becca = c+ c Too little information given to choose an answer

Sam = c+ Y, Becca = c+ c

Part complete Which of the following are involved in the initiation of translation? Origin of replication, RNA primers, enzymes Promoter, transcription factors, RNA polymerase Telomere, stop codon Start codon, ribosome, mRNA, tRNA Operator, operon, repressor

Start codon, ribosome, mRNA, tRNA

An old DNA strand is used as a _____ for the assembly of a new DNA strand. source of nucleotides model primer complement template

Template (An old DNA strand is used as a template for the synthesis of a complementary new strand)

In an organism's DNA, what makes one nucleotide different from another? The sugar The phosphate The base Only some nucleotides have carbon atoms Only some nucleotides have nitrogen atoms

The base

During transcription in eukaryotes, a type of RNA polymerase called RNA polymerase II moves along the template strand of the DNA in the 3'→5' direction. However, for any given gene, either strand of the double-stranded DNA may function as the template strand. For any given gene, what ultimately determines which DNA strand serves as the template strand? the base sequence of the gene's promoter which of the two strands of DNA carries the RNA primer the location of specific proteins (transcription factors) that bind to the DNA the location along the chromosome where the double-stranded DNA unwinds

The base sequence of the gene's promoter (In eukaryotes, binding of RNA polymerase II to DNA involves several other proteins known as transcription factors. Many of these transcription factors bind to the DNA in the promoter region (shown below in green), located at the 3' end of the sequence on the template strand. Although some transcription factors bind to both strands of the DNA, others bind specifically to only one of the strands. Transcription factors do not bind randomly to the DNA. Information about where each transcription factor binds originates in the base sequence to which each transcription factor binds. The positioning of the transcription factors in the promoter region determines how the RNA polymerase II binds to the DNA and in which direction transcription will occur.)

Part complete Each strand of a DNA molecule can act as a template for DNA replication because The rules of complementary base pairing dictate exactly what the sequence of nucleotides in a newly synthesized strand should be. Your entire genome sequence is stored in your brain, and your brain tells each copy of the DNA polymerase enzyme what to do. The two strands of a DNA molecule are exactly the same. The two chromosomes in a homologous pair are identical to each other. Genes that are read during transcription may be found in either strand of the DNA molecule.

The rules of complementary base pairing dictate exactly what the sequence of nucleotides in a newly synthesized strand should be.

In the diagram below, the green unit represents _____. The figure shows a blue molecule arranged in the form of a double chain. The gray unit on this figure represents an oval structure which contains unwound and unpaired chains of this molecule. Before and after this unit, the molecule is wound in the form of a double helix. A green unit represents a part of the double helix before the gray unit. RNA DNA transcription factors RNA polymerase the promoter

The promoter (The promoter is the region of DNA at which the process of transcription begins.)

Which of the following statements best describes the promoter of a protein-coding gene? The promoter is part of the RNA molecule itself. The promoter is a site found on RNA polymerase. The promoter is a site at which only RNA polymerase will bind. The promoter is a nontranscribed region of a gene.

The promoter is a nontranscribed region of a gene. (The promoter is the regulatory region of a protein-coding gene at which RNA polymerase must bind to initiate transcription—it is not transcribed into the RNA.)

In general, the most important step of gene expression for gene regulation in eukaryotes is transcription. RNA processing. translation. degradation (break down) of mRNAs. degradation (break down) of proteins.

Transcription

What is the process called that converts the genetic information stored in DNA to an RNA copy? Translation Transcription Replication Translocation

Transcription (DNA is transcribed to give an RNA copy.)

What name is given to the process in which a strand of DNA is used as a template for the manufacture of a strand of pre-mRNA? RNA processing gene expression polypeptide formation transcription translation

Transcription (Transcription is the process by which a DNA template is used for the manufacture of several different types of RNA)

Viral DNA makes mRNA by the process of _____. replication infection translation lysis transcription

Transcription (Viral DNA co-opts the cell's reproductive machinery

A hypothetical man has brown hair on the top of his head, yet the hair in his beard is red. The best explanation for this is that cells on his face have _____________ that are different from those in the cells on the top of his head. genomes transcription factors genes enhancers and promoters numbers of chromosomes

Transcription factors

What name is given to the process in which the information encoded in a strand of mRNA is used to construct a protein? RNA processing gene expression polypeptide formation transcription translation

Translation (Translation is the process by which information encoded in RNA is used to manufacture a polypeptide)

Which of the following is FALSE about viruses? Viruses are made of cells Viruses have nucleic acids Viruses have genomes Viruses have proteins Viruses are intracellular parasites

Viruses are made of cells

Sort the items according to whether they may be found only in free virus particles, only in uninfected host cells, or in both viruses and host cells: Protein Evelope with glycoproteins RNA Capsid DNA Capsomere (core protein)

Viruses: Capsid, capsomere (core protein), envelope with glycoproteins Host cell only: ribosome Both: Protein, RNA, DNA

Bob has a genetic condition that affects his skin. Bob's wife, Eleanor, has normal skin. No one in Eleanor's family has ever had the skin condition. Bob and Eleanor have a large family. Of their eleven children, all six of their sons have normal skin, but all five of their daughters have the same skin condition as Bob. Based on Bob and Eleanor's family history, what inheritance pattern does the skin condition most likely follow? X-linked recessive autosomal dominant Y-linked X-linked dominant autosomal recessive

X-linked dominant (If the skin condition is caused by an X-linked dominant allele, a father would pass the allele on to all of his daughters, who would all have the skin condition. In contrast, the father would not pass the allele on to any of his sons because the sons would receive the father's Y chromosome, not his X chromosome. As a result, none of the sons would inherit the skin condition.)

Suppose that a single DNA base change of an "A" to a "T" occurs and is copied during replication. Is this change necessarily a mutation? Yes, it is a change in the DNA sequence. Yes, if the base change occurs in a gamete (sperm or egg cell); otherwise no. Yes, if the base change occurs in the coding part of a gene; otherwise no. Yes, if the base change occurs in the coding part of a gene and alters the amino acid sequence of a protein; otherwise no. Yes, if the base change alters the appearance of the organism (phenotype); otherwise no.

Yes, it is a change in the DNA sequence.

Generally speaking, which of the following mutations would most severely affect the protein coded for by a gene? a base substitution at the beginning of the gene a base substitution at the end of the gene a frameshift deletion at the beginning of the gene a frameshift deletion at the end of the gene

a frameshift deletion at the beginning of the gene (A frameshift mutation at the beginning of a gene would affect every codon after the point where the mutation occurred. During protein synthesis, incorrect amino acids would be inserted from the point where the frameshift mutation occurred on; the resulting protein would most probably be nonfunctional. For this reason, a frameshift mutation at the beginning of a gene is generally the most severe type of mutation)

During RNA processing a(n) _____ is added to the 3' end of the RNA. 3' untranslated region a long string of adenine nucleotides 5' untranslated region coding segment modified guanine nucleotide

a long string of adenine nucleotides (A poly-A tail is added to the 3' end of the RNA.)

In molecular terms, a gene is best defined as the DNA molecule in a chromosome. a sequence of DNA that codes for a protein. an enzyme. a signal to stop translation. several introns bonded together.

a sequence of DNA that codes for a protein.

A virus's genome could NOT be in the form of single-stranded RNA. single-stranded DNA. double-stranded RNA. a sequence of amino acids. double-stranded DNA.

a sequence of amino acids.

Which of the following functions do RNA molecules perform during translation? catalyzing the formation of bonds between amino acids carrying amino acids providing a site for building a protein holding a "message" from the DNA all of these answers

all of these answers

Elongation during transcription directly involves RNA polymerase. complementary base pairing. the synthesis of a nucleic acid. the formation of bonds in a sugar-phosphate backbone. all of these answers.

all of these answers.

For the following question, please use the following information: In humans, a recessive allele of a gene on the X chromosome causes humans to be "colorblind." A man with normal vision and a colorblind woman have children together. We can expect that _________ of their sons and _________ of their daughters will be colorblind. half, none none, half all, half half, all all, none

all, none

What is the event that IMMEDIATELY follows the last event of this animation? To view the animation, click here. Then click on the image to start the animation. unbending of the DNA and the release of RNA polymerase from the promoter binding of the activators to enhancers transcription binding of mRNA to the smaller ribosomal subunit binding of RNA polymerase to the promoter

binding of RNA polymerase to the promoter (The bending of the DNA allows for the interaction of transcription factors and RNA polymerase)

If allele combinations are always preserved ("strict dependent assortment"), which combinations of traits should NEVER be observed? black body with normal wings AND black body with vestigial wings black body with vestigial wings gray body with normal wings black body with normal wings AND gray body with vestigial wings gray body with normal wings AND gray body with vestigial wings

black body with normal wings AND gray body with vestigial wings

Elongation during translation directly involves RNA polymerase. complementary base pairing. the synthesis of a nucleic acid. the formation of bonds in a sugar-phosphate backbone. all of these answers.

complementary base pairing.

Translation occurs in the _____. cytoplasm lysosome nucleus Golgi apparatus nucleoplasm

cytoplasm (Ribosomes, the sites of translation, are found in the cytoplasm)

After DNA replication is completed, _____. Each new DNA double helix consists of one old DNA strand and one new DNA strand One DNA double helix consists of two old strands and one DNA double helix consists of two new strands There are four double helices each new DNA double helix consists of two new strands Each of the four DNA strands consists of some old strand parts and some new strand parts

each new DNA double helix consists of one old DNA strand and one new DNA strand

Which of the following does NOT require regulation of gene expression? Having different cells with different functions The development of distinct organs within the body Turning the synthesis of a protein on and off as needed Expressing a gene all the time, regardless of conditions Making the protein hemoglobin only in cells that need to transport oxygen

expressing a gene all the time, regardless of conditions

Which of the following functions do RNA molecules perform during transcription? catalyzing the formation of bonds between amino acids carrying amino acids providing a site for building a protein holding a "message" from the DNA all of these answers

holding a "message" from the DNA

What is the source of a viral envelope? host cell DNA prophages provirus host cell membrane viral glycoproteins

host cell membrane (The viral envelope is derived from host cell membrane)

DNA replication, transcription, and translation all directly require RNA polymerase. hydrogen bonding between complementary nucleotide bases. DNA polymerase. ribosomes. transcription factors.

hydrogen bonding between complementary nucleotide bases.

RNA processing converts the RNA transcript into _____. a protein DNA a eukaryotic cell mRNA a polypeptide

mRNA (The editing of the RNA transcript produces mRNA)

Disruption of the gradient of an inducer (i.e., an inductive signal) during an animal's development would NOT be expected to result in altered pattern formation. altered development along one of the body axes. increased numbers of mutations in the animal's DNA. abnormal gene regulation in some of the animal's cells. missing body parts.

increased numbers of mutations in the animal's DNA.

The "central dogma" of biology explains how life arose on this planet. the union of sperm and egg creates the next generation. DNA is replicated. new species evolve. information stored in DNA comes to life in two fundamental steps.

information stored in DNA comes to life in two fundamental steps

During RNA processing a(n) _____ is added to the 5' end of the RNA. 3' untranslated region a long string of adenine nucleotides 5' untranslated region coding segment modified guanine nucleotide

modified guanine nucleotide (The 5' cap consists of a modified guanine nucleotide)

Which of the following RNA molecules catalyzes reactions (i.e., catalyzes the formation of chemical bonds) during translation? mRNA pre-mRNA rRNA tRNA none of these.

rRNA

Which of the following do not associate with (i.e., bind to) transcription factors during transcription initiation in eukaryotes? enhancers promoters ribosomes additional transcription factors RNA polymerase

ribosomes

The genetic material of HIV consists of _____. single-stranded DNA single-stranded RNA double-stranded DNA double-stranded RNA none of the above

single-stranded RNA (The genetic material of HIV consists of two molecules of single-stranded RNA)

Spliceosomes are composed of _____. small RNAs and proteins polymerases and ligases introns and exons the RNA transcript and protein

small RNAs and proteins (Spliceosomes are complexes composed of small RNAs and proteins)

The bicoid gene product is directly responsible for _____ in a developing Drosophila embryo. the establishment of the right-left axis vulval development flower development the establishment of the anterior-posterior axis apoptosis

the establishment of the anterior-posterior axis (The concentration gradient of bicoid protein determines the anterior-posterior axis of a developing Drosophila)

Suppose you counted 1000 offspring from cross (iii), and 800 of the offspring had either a gray body with normal wings OR a black body with vestigial wings. From this you should conclude that ... the two genes are on the same chromosome, 20 map units apart the two genes are on the same chromosome, 80 map units apart something went wrong in your experiment alleles of the two genes assort independently the genes are both on the X chromosome

the two genes are on the same chromosome, 20 map units apart

In a DNA double helix an adenine of one strand always pairs with a(n) _____ of the complementary strand, and a guanine of one strand always pairs with a(n) _____ of the complementary strand. cytosine ... thymine uracil ... cytosine guanine ... adenine cytosine ... uracil thymine ... cytosine

thymine ... cytosine

In cats, females usually have two X chromosomes, and males usually have one X and one Y chromosome. In cats, black fur color is caused by an X-linked allele; the other allele at this locus causes orange color. The heterozygote is tortoiseshell. What kinds of offspring would you most commonly expect from the cross of an XX black female and an XY orange male? orange females; black males tortoiseshell females; black males tortoiseshell females; tortoiseshell males orange females; orange males black females; orange males

tortoiseshell females; black males