Which of the following shows the appearance of the DNA strands that would result after two rounds of DNA replication? Note that the black strands represent DNA present in the original DNA molecule. The grey strands represent newly-synthesised DNA.
A DNA profile was created for two genes in three individuals (A, B, and C).
Which of the following statements, relating to the images provided, are correct?
The relationship between DNA fragment length and distance moved through the gel is linear.
Fragment length is determined by the number of VNTRs.
There is a percentage increase of 50 % between the distance moved by fragment Y and that moved by fragment X.
I, II, and III only.
I, II, III, and IV.
II and IV only.
III and IV only.
Which row correctly identifies the enzymes in a replication fork?
| I | II | III | IV | V | |
| A. | DNA primase | DNA ligase | DNA polymerase I | Helicase | DNA polymerase III |
| B | DNA polymerase III | DNA ligase | DNA polymerase I | Helicase | DNA primase |
| C. | DNA primase | DNA ligase | DNA primase | DNA polymerase III | DNA polymerase I |
| D. | DNA polymerase I | DNA polymerase III | DNA ligase | DNA gyrase | DNA helicase |
Which of the following statements about DNA sequencing are correct?
Fragments of different length can be separated using gel elecrophoresis.
PCR requires the use of primers, deoxyribonucleotides, RNA polymerase, and labelled dideoxyribonucleotides.
The terminator nucleotide indicates the base present at each position in the sequence.
Dideoxynucleotides are incorporated at specific points in the DNA sequence.
I, II, and II only
I and III only.
II and III only.
III and IV only.
Hershey and Chase carried out an experiment to determine whether the molecule of heredity was protein or DNA; their results after centrifugation are shown below.
Note the following:
Which of the following can be concluded from the results shown?
No viral protein enters the infected bacterial cells.
DNA has a greater mass than protein.
Around 80 % of the viral DNA enters the infected bacterial cells.
Most proteins are separated from the bacterial cells by the blending process.
