bio 101 exam 4
Cytosine makes up 32% of the nucleotides in a sample of DNA from an organism. Approximately what percentage of the nucleotides in this sample will be thymine?
18
Adds DNA nucleotides at the 3' end using a DNA template strand to pair complementary bases
DNA polymerase
For the following mRNA strand, indicate the correct polypeptide sequence that will be produced: 3'GCAUCAGCAAGG5.' (The Codon Table is on the last page of your exam.)
GLY - THR - THR - THR
Unwinds the DNA double helix
helicase
Natural selection is based on all of the following except
individuals adapt to their environments and, thereby, evolve.
Repairs any breaks in the sugar-phosphate backbone; joins okazaki fragments
ligase
DNA replication is called semiconservative because
the two resulting DNA molecules each have one new DNA strand and one old strand from the original DNA molecule.
An RNA copy of the DNA template strand is made. This describes the process of ____________, which takes place in the ______________.
transcription; nucleus
The type of RNA that brings the correct amino acid to the ribosome so it can be added to the growing polypeptide chain is _____________ RNA.
transfer
Which of the following processes does not occur within the nucleus?
translation
A DNA template strand reads 3'TTACGGAC5'. During DNA Replication, what specific complementary DNA sequence will be added to the growing new strand?
5'AATGCCTG3'
Complete the sentence with the MOST CORRECT answer. One gene codes for one
Polypeptide
What kind of chemical bond is found between paired bases of the DNA double helix?
hydrogen
A particular triplet of bases in the template strand of DNA is 5'ACG3'. The corresponding codon for the mRNA transcribed is
3' UGC 5'
During RNA Processing, which of the following are added to help(s) to stabilize mRNA by inhibiting its degradation?
5' cap and poly (A) tail
Which one of the following point mutations is most likely to have no effect on the final protein product?
A silent mutation
Suppose you are provided with an actively dividing culture of E. coli bacteria to which radioactive thymine has been added. What would happen if a cell replicates once in the presence of this radioactive base?
DNA in both daughter cells would be radioactive
A new DNA strand elongates only in the 5' to 3' direction because
DNA polymerase can only add nucleotides to the free 3' end.
In translation, what is the function of the release factor (RF)?
It binds to the stop codon in the A site in place of a tRNA
What effect will the mutation described in Question #19 have on the polypeptide strand that is synthesized from it?
It will change an amino acid. The amino acid "Asp" will be changed to "Glu."
Characteristics that an organism acquires during their lifetime are NOT normally inherited by offspring. Which of the following scientists came up with the idea of "inheritance of acquired characteristics?"
Jean-Baptiste de Lamarck
A point mutation occurs, changing the DNA template strand from 3'CTG5' to 3'CTC5'. What type of mutation is this?
Missense
Which of the following best describes Chargaff's base-pair bonding rules?
Pyrimidines always bind to purines
During DNA Replication, the DNA strand that is synthesized as short Okazaki fragment is called the
the lagging strand
What determines the nucleotide sequence of the newly synthesized strand during DNA replication?
the nucleotide sequence of the template strand