Nurs 251 actual exam Questions and Correct
Solutions
A point mutation that changes a codon specifying an amino acid into a stop codon is called
a
frameshift mutation.
nonsense mutation.
missense mutation.
deletion mutation.
nonsense mutation
The triplet code of CAT in DNA is represented as ______ in mRNA and ______ in tRNA,
respectively.
Correct!
CAU, GUA
CAU, GTA
CAT, CAT
,CAT, GAA
CAU, GUA
What is the relationship among genes, DNA, and proteins?
Proteins are the nitrogenous bases that form double strands of DNA in its helical shape.
A gene is a section of DNA that provides the directions for synthesizing a specific protein.
Protein is composed of DNA that is organized into specific gene sequences called amino
acids.
DNA is composed of a series of amino acids that provide the directions for synthesizing
proteins.
A gene is a section of DNA that provides the directions for synthesizing a specific protein.
What is the expected result of a "nonsense" point mutation?
No change in amino acid sequence and no change in the composition of the protein product
,Replacing an amino acid codon with a "stop" codon, resulting in a truncated protein
product
Total disruption of the gene reading frame, no production of protein
Replacement of one amino acid with another in the final gene product
Replacing an amino acid codon with a "stop" codon, resulting in a truncated protein product
What is the function of ribosomes (also known as ribosomal RNA) in protein synthesis?
Serves as a transport molecule able to move a specific amino acid to the site of protein
synthesis (peptide chain elongation) in the correct sequence
Serves as the coordinator mechanism to allow proper reading of the mRNA and placement
of the correct amino acid in the sequence by the tRNAs
Allows interpretation of the two strands of DNA to determine which is the "sense" strand
and which is the "antisense" strand
, Allows further processing of synthesized proteins (post-translational modification in order
to ensure that the final product is physiologically active)
Serves as the coordinator mechanism to allow proper reading of the mRNA and placement of the
correct amino acid in the sequence by the tRNAs
Which of the following is not needed for DNA transcription?
Ribosome
Enzymes
Nucleotides
DNA
Ribosome
Frameshift mutations
applies to the reading frame (sequence of codons) being changed.
can occur when one of more nucleotides is deleted from a DNA sequence.
can occur when one or more nucleotides are inserted into a DNA sequence.
Solutions
A point mutation that changes a codon specifying an amino acid into a stop codon is called
a
frameshift mutation.
nonsense mutation.
missense mutation.
deletion mutation.
nonsense mutation
The triplet code of CAT in DNA is represented as ______ in mRNA and ______ in tRNA,
respectively.
Correct!
CAU, GUA
CAU, GTA
CAT, CAT
,CAT, GAA
CAU, GUA
What is the relationship among genes, DNA, and proteins?
Proteins are the nitrogenous bases that form double strands of DNA in its helical shape.
A gene is a section of DNA that provides the directions for synthesizing a specific protein.
Protein is composed of DNA that is organized into specific gene sequences called amino
acids.
DNA is composed of a series of amino acids that provide the directions for synthesizing
proteins.
A gene is a section of DNA that provides the directions for synthesizing a specific protein.
What is the expected result of a "nonsense" point mutation?
No change in amino acid sequence and no change in the composition of the protein product
,Replacing an amino acid codon with a "stop" codon, resulting in a truncated protein
product
Total disruption of the gene reading frame, no production of protein
Replacement of one amino acid with another in the final gene product
Replacing an amino acid codon with a "stop" codon, resulting in a truncated protein product
What is the function of ribosomes (also known as ribosomal RNA) in protein synthesis?
Serves as a transport molecule able to move a specific amino acid to the site of protein
synthesis (peptide chain elongation) in the correct sequence
Serves as the coordinator mechanism to allow proper reading of the mRNA and placement
of the correct amino acid in the sequence by the tRNAs
Allows interpretation of the two strands of DNA to determine which is the "sense" strand
and which is the "antisense" strand
, Allows further processing of synthesized proteins (post-translational modification in order
to ensure that the final product is physiologically active)
Serves as the coordinator mechanism to allow proper reading of the mRNA and placement of the
correct amino acid in the sequence by the tRNAs
Which of the following is not needed for DNA transcription?
Ribosome
Enzymes
Nucleotides
DNA
Ribosome
Frameshift mutations
applies to the reading frame (sequence of codons) being changed.
can occur when one of more nucleotides is deleted from a DNA sequence.
can occur when one or more nucleotides are inserted into a DNA sequence.
