AQA
A-Level
BIOLOGY
3.1 | Biological Molecules
4.1|Proteins and Enzymes
Time allowed
62 minutes
QUESTION PAPER
Score Percentage
/52 %
4.1 | CELL BIOLOGY | QUESTION PAPER 1 1
,Figure 1 shows one base pair of a DNA molecule.
Figure 1
(a) Name part F of each nucleotide.
........................................................................................................................
(1)
(b) Scientists determined that a sample of DNA contained 18% adenine.
What were the percentages of thymine and guanine in this sample of DNA?
Percentage of thymine
Percentage of guanine
(2)
, During replication, the two strands of a DNA molecule separate and each acts as a
template for the production of a new strand.
Figure 2 represents DNA replication.
Figure 2
(c) Name the enzyme shown in Figure 2.
........................................................................................................................
(1)
The arrows in Figure 2 show the directions in which each new DNA strand is being
produced.
(d) Use Figure 1, Figure 2 and your knowledge of enzyme action to explain why the
arrows point in opposite directions.
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
(4)
(Total 8 marks)
A-Level
BIOLOGY
3.1 | Biological Molecules
4.1|Proteins and Enzymes
Time allowed
62 minutes
QUESTION PAPER
Score Percentage
/52 %
4.1 | CELL BIOLOGY | QUESTION PAPER 1 1
,Figure 1 shows one base pair of a DNA molecule.
Figure 1
(a) Name part F of each nucleotide.
........................................................................................................................
(1)
(b) Scientists determined that a sample of DNA contained 18% adenine.
What were the percentages of thymine and guanine in this sample of DNA?
Percentage of thymine
Percentage of guanine
(2)
, During replication, the two strands of a DNA molecule separate and each acts as a
template for the production of a new strand.
Figure 2 represents DNA replication.
Figure 2
(c) Name the enzyme shown in Figure 2.
........................................................................................................................
(1)
The arrows in Figure 2 show the directions in which each new DNA strand is being
produced.
(d) Use Figure 1, Figure 2 and your knowledge of enzyme action to explain why the
arrows point in opposite directions.
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
(4)
(Total 8 marks)
