Name:______Date:______Period:______

Replication

  1. What is the difference between the lagging strand and the leading strand?

Describe the function of the following enzymes involved in replication

  1. DNA helicase –
  2. DNA ligase –
  3. DNA polymerase –
  4. RNA primase –
  5. The template strand of a piece of DNA being replicated reads: 5'-ATAGGCCGT-3'. A partially synthesized Okazaki fragment is 5'CCTA3'. If the next fragment is four bases long, what is its first base?

DNA Repair

  1. This segment of DNA has undergone a mutation in which six nucleotides have been deleted. A repair enzyme would replace them. Which series of bases will complete the strand of DNA?
  1. A particular sequence of parent DNA has five purine bases and two pyrimidine bases. According to base-pairing rules, which of the following sequences could be formed during replication?

a.two cytosine, three adenine, two thymine

b.two cytosine, three adenine, two uracil

c.three adenine, two thymine, one guanine, one cytosine

d.three adenine, two guanine, two cytosine

  1. Explain how replication occurs, include enzymes involved and describe the semi-conservative nature of DNA replication.

Name:______Date:______Period:______

Transcription

  1. Where does transcription occur?
  2. Describe the function of RNA polymerase –
  1. Write the complementary mRNA for the following DNA template strands:
  2. ATGCATTG
  3. GGTCTAGG
  4. TCGGATCG
  5. TACGCGTA
  6. This is a template DNA sequence: 3'AATCGC5'. This is a partially-completed mRNA strand transcribed from the DNA template: 3'GCGA5'. What is the next nucleotide that RNA polymerase will attach?
  1. What are two ways that messenger RNA is processed prior to translation?
  2. What are exons?
  1. Here are two related mRNA sequences: 5'UUUAGCGAGCAU3' and 5'UUUAGCCAUAAAAAAAA3'. How was the second sequence formed?

a. / a tandem repeat mutation formed the second sequence
b. / processing removed an exon and added a poly-A tail to form the second sequence
c. / processing removed an intron and added a poly-A tail to form the second sequence
d. / RNA polymerase matched up several incorrect nucleotide bases to the original DNA as the second sequence formed

Name:______Date:______Period:______

Translation

  1. In which part of the cell does this process shown above take place?
  2. Structure I in the figure above represents a(n) ______
  3. Structure II in the figure above represents a(n) ______
  4. Structure III in the figure above represents a(n) ______
  5. Structure IV in the figure above represents a(n) ______
  6. Structure IV in the figure above represents a(n) ______
  7. What is translation?
  1. Which of the structures in the figure above are composed of RNA?

The messenger RNA codes for six different amino acids are shown in the table below.

  1. In one type of mutated gene for hemoglobin, CAC has replaced the normal CTC in the DNA code. What amino acid substitution has taken place in the mutated hemoglobin?
  1. Why is it possible for an amino acid to be specified by more than one kind of codon?

Translate the following messenger RNA sequences

  1. UAC CGU GGA
  2. CGC ACA GCA
  3. CCA ACC AGA
  4. AUG GCC UAC
  5. GGU CUA GUU
  6. UAG AUG CCC
  7. CCG CAU UGG
  8. GAC AAU UCG
  9. AUG UUU UAA
  1. Which of the following would be least likely to happen as a result of a mutation in a person's skin cells?

a.skin cancer

b.reduced functioning of the skin cell

c.no change in functioning of the skin cell

d.the person's offspring have mutated skin