BIO Chapter 10

What is the complementary mRNA sequence to the DNA sequence below? 3'-AGTCAG-5'

UCAGUC

Bacteria produce proteins (called "repressors") that bind to the promoter and block RNA polymerase from binding to structural genes. An increase in production of repressor will a. increase transcription of the structural gene. b. decrease transcription of the structural gene. c. alter the gene sequence of the structural gene. d. prevent RNA polymerase from binding to any promoter in the genome.

b

Place the elements in the flow of information during gene expression in the correct sequence.

dna, rna, protein

t or f: The fact that ACU, ACC, ACA, and ACG all encode for the amino acid threonine is an example of the redundancy of the genetic code.

t

The redundant nature of the genetic code provides multiple ways for DNA to encode for one amino acid.

x

The start codon is a three nucleotide sequence, AUG, in mRNA that informs the ribosome the exact location where protein synthesis should begin.

x

The viral genes introduced into the eggs are expressed just as the hemagglutinin gene is expressed in the tobacco plant.

x

without the ___________ site on molecule dna, ___________ cannot bind to the dna to begin the process of ___________

promoter, rna, polymerase, transcription

Which molecule is most directly responsible for a cell's phenotype?

proteins

a mutation to the tRNA changes the amino acid bound to the tRNA with the anticodon of AGG from serine to alanine. How will this affect the cell?

the cell will add the wrong amino acid when the mRNA has the codon UCC

Compare and contrast the genetic code in plants and humans.

The genetic code is identical for both plants and humans

A gene contains the sequence GGCTAAC What is the sequence of the mRNA transcribed from this strand of DNA?

CCGAUUG

a small segment of DNA is used as a template for transcription. This contains the base sequence CGT. If an mRNA transcript is made that includes this sequence, what would be the anticodon on the tRNA that would bind to this corresponding mRNA sequence?

CGU

The process of gene transcription begins with the

binding of RNA polymerase to a region of DNA called the "promoter."

Which amino acid does the mRNA codon AAG code for?

lysine

Match each type of RNA to its role in translation. template for synthesis of protein

mrna

Match each type of RNA to its role in translation. assists in covalently bonding amino acids together to make a protein

rrna

Which amino acid does the mRNA codon GUU code for?

valine

Which of the following is a way that gene expression is regulated in a cell? Correct Answer(s) controlling protein breakdown controlling transcription controlling translation

all of the above

t or f: Once an organism inherits its alleles, nothing can be done to change the phenotype of those alleles.

f

A gene is responsible for producing an enzyme that is used to make tryptophan (an amino acid) in bacteria. If the cell has enough tryptophan and doesn't need any more, it would most likely

use an inhibitor to block the RNA polymerase from binding to the promoter

Prokaryotes lack membrane-enclosed organelles and thus do not have nuclei. Therefore,

prokaryotic transcription and translation both take place in the cytoplasm.

AUG is the start codon, coding for methionine, ACA codes for threonine, and UGA is a stop codon.

x

The genetic code is made of codons that are ________ base(s) long.

3

Refer to the following information on the genetic code. Use this information to determine how many amino acids are coded for by the mRNA sequence AUGCGCAGUCGGUAG

4

How many amino acids should be present in the protein translated from the following mRNA sequence? AUG-AAC-GGG-CCA-UGA

4 AUG is the start codon, coding for methionine, and UGA is a stop codon, which does not produce an amino acid. The protein would be Met-Asn-Gly-Pro.

Consider a complete, functional piece of mRNA that contains a total of 66 codons. What is the maximum number of amino acids that could be present in the protein coded for by this mRNA?

65

Medicago is using tobacco plants to generate flu vaccines by engineering plants that express viral genes. Use the codon table below to identify the three amino acids that would be encoded by the following codons, in the order in which they would be added to the growing peptide chain. CAA UGU CUC

Gln Cys Leu

When nutrients are scarce, cells will often reduce the number of ribosomes present in the cell. What effect would this have on gene expression? Translation would occur less often, resulting in less protein. mRNA would become less stable, resulting in less translation. Transcription would occur less often, resulting in less mRNA. Proteins would become less stable, resulting in fewer ribosomes.

a

The - that an organism inherits from its parents influence its phenotype. Phenotypes can also be influenced throughout an organism's lifetime by - the expression of particular genes. For example, - the expression of an allele will often accentuate that allele's phenotype.

alleles, changing, increasing

Each set of three bases in an mRNA molecule codes for one of 20 specific a. rRNA molecules. b. nucleotides. c. amino acids. d. proteins.

c

If you expose a cell to chemicals that specifically disrupt the function of RNA polymerase, which of the following processes will be most directly affected? a. mutation b. translation c. transcription d. RNA splicing

c

The order of the bases in DNA determines the order of the a. amino acids in DNA. b. bases in a protein. c. amino acids in mRNA. d. bases in mRNA.

d

Which of the following does NOT take place in the nucleus a. transcription b. intron removal c. replication d. translation d. translation

d

Match each of the following molecules to their likely part in the production of dark eye color. used as template for production of mRNA

dark eye color allele

Match each of the following molecules to their likely part in the production of dark eye color. used as template for production of protein

dark eye color mrna

Match each of the following molecules to their likely part in the production of dark eye color. the pigment that produces dark eye color phenotype

dark eye color protein

t or f: Changing gene expression changes the sequence of the gene.

f

A sequence of DNA that contains information for the synthesis of RNA molecules used in the manufacture of proteins is also known as a(n)

gene

The allele combination at a gene locus is known as an organism's -. The DNA - is then transcribed to produce -, using the DNA as a template. The resultant molecule is then transferred to the - where it is used as a template to construct -, which are responsible for producing the organism's -.

genotype, sequence, mRNA, cytoplasm, proteins, phenotype

For the information contained in a gene to be used to produce a functioning protein,

information must be transcribed into mRNA and then translated into amino acids.

What should be the second amino acid in the protein translated from the mRNA sequence below? Be sure to consider that translation always begins with a very specific codon. AGGAUGCCGUUG

proline Proline should be the second amino acid in this protein. According the genetic code, AUG is the start codon and produces methionine, and CCG codes for proline.

After studying a freshly discovered meteor, you are astounded to find a single-celled organism living in it, representing the world's first extraterrestrial life-form. After extensive biochemical tests, you determine that the organism uses the same nucleotides as life on Earth, that it uses 50 different amino acids, and that each "codon" in its genome consists of four bases, not three, resulting in 256 possible combinations. Based on this information, does this genetic code fit our definition for redundant or universal?

redundant

The biotech company Medicago expresses viral genes in tobacco plants to generate flu vaccines. In the genetic code, the codons CAU and CAC both encode amino acid histidine. This ability to interchange multiple codons for a single amino acid is an example of how the genetic code is __________.

redundant

t or f: A mutation in a gene that disrupts its ability to transcribe a complete mRNA molecule would likely result in a change in the organism's phenotype.

t

t or f: Changes in gene expression alter the behavior of the gene, changing the amount of protein that is produced by the gene; its genotype is unaffected by this regulation.

t

t or f: Phenotypically, zero expression of an allele could look similar to not possessing the allele at all

t

t or f: A mutation in a tRNA anticodon may result in a change in the amino acid sequence.

t

t or f: During an organism's lifetime, the phenotype of an allele can be altered by changes in gene expression.

t

t or f: Given the genetic code, one could predict the protein sequence that would be produced from any given DNA sequence.

t

t or f: That the genetic code is universally used by organisms as diverse as bacteria and humans is evidence that these organisms possess a common ancestor.

t

The process in which mRNA is used as a template to construct a protein is called -. During this process, an amino acid is brought to the mRNA by a -, which temporarily binds to a three nucleotide sequence in the mRNA known as a -. The genetic code determines which amino acid will be brought next, based on the mRNA sequence.

translation, tRNA, condon

Match each type of RNA to its role in translation. escort for new amino acids

trna

A particular protein is responsible for dark spots on a butterfly wing. Which of the following would result in darker wing spots? Correct Answer(s) increased rates of translation decreased rates of mRNA breakdown Incorrect Answer(s) decreased rates of transcription increased rates of protein breakdown

x

A phenotype is created from a gene via gene expression. A mutation in a gene that disrupts transcription almost certainly would disrupt translation, altering the organism's phenotype.

x

Decreasing which of the following would result in down-regulation of gene expression? Correct Answer(s) rate of transcription rate of translation Incorrect Answer(s) rate of protein breakdown rate of mRNA breakdown

x

During translation, the amino acid chain already present at the ribosome (i.e., blue, red) is transferred from the tRNA to the amino acid that has just arrived (i.e., green), which is still attached to its tRNA.

x

For the following partial beginning of the coding region of an mRNA sequence, use the genetic code table below to determine the effects of the bolded, underlined U being mutated to C. Then answer the question below. 5'-AUG UCU CCU CAA Based on this mutation, which of the following statements is correct? Correct Answer(s) Due to redundancy in the genetic code, a change in the third nucleotide of a codon often leads to no change in the amino acid sequence. If the U is mutated to C, the mRNA will still encode for the amino acid proline. Incorrect Answer(s) If the U is mutated to C, the mRNA will now encode for a stop codon. Nearly all changes to a nucleotide sequence will lead to a significant adverse impact on the amino acid sequence.

x

Of the two methods, only the tobacco plant method requires expression of viral genes. XIncorrect choiceThis statement is false because both vaccines are capable of stimulating an immune response. XIncorrect choiceThis statement is true because the tobacco plant method transfers genes from one organism to another. XIncorrect choiceThis statement is true because the viruses harvested from the egg method are inactive. √Correct choiceThis statement is false because gene expression is also needed to make viruses in the eggs.

x

Place the following steps of transcription in the correct order. RNA polymerase binds to a promoter. RNA polymerase unzips the DNA double helix. RNA polymerase makes mRNA using DNA as a template. RNA polymerase stops polymerizing RNA when it reaches a terminator.

x

Place the steps of translation in the correct order. The ribosome scans the mRNA for the presence of a start codon. tRNAs bind to the start codon located on the mRNA. The ribosome links together amino acids attached to the tRNAs. The ribosome continues until it reaches a stop codon.

x

The biotechnology company Medicago is using tobacco plants to generate vaccines. Which of the following statements correctly describe how this company uses gene expression to generate the vaccines? Correct Answer(s) The tobacco plant's phenotype is altered by introducing the gene required to produce hemagglutinin. The tobacco plant's genotype is altered by introducing the gene required to produce hemagglutinin. Incorrect Answer(s) By introducing a new gene into the tobacco plants, Medicago created a new organism. Although Medicago adds an extra gene into the tobacco plants, it is still tobacco, and therefore the genotype is unchanged.

x

Which of the following is a likely result outcome of the introduction of a mutation into a gene responsible for making protein X? Correct Answer(s) change in shape of the gene's protein change in the sequence of the gene's mRNA change in the sequence of the gene's protein Incorrect Answer(s) a mutation in other genes that regulate protein X production

x

Which of the following is a way in which gene expression can be regulated before transcription? Correct Answer(s) changes in DNA packing Incorrect Answer(s) changes in number of DNA strands changes in DNA length

x

Which of the following might have been the mRNA sequence that was translated into the amino acid sequence below? Met-Ala AUG is the start codon, which codes for methionine. GCC codes for alanine, and UGA is a stop codon.

x

Which of the following organisms uses the genetic code to translate mRNA sequences into protein sequences? Correct Answer(s) bacteria humans spiders pine trees

x

Which of the following traits is found in nearly all organisms on Earth? Correct Answer(s) the genetic code mRNA DNA

x