This document contains exam done on June 2022 OCR AS Level Biology B (Advancing Biology) H022/02 Biology in depth Question Paper. Download to score A.
Answer all the questions.
1 Fig. 1.1 shows a prepared slide of onion cells in different stages of mitosis, viewed using a light
microscope.
A
B
C
Fig. 1.1
(a) (i) Name the stages of mitosis taking place in cells A and B.
A ........................................................................................................................................
B ........................................................................................................................................
[2]
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(ii) Fig. 1.2 shows a student’s drawing of the cell labelled C in Fig. 1.1.
Fig. 1.2
Give two improvements the student could make to their drawing.
1 ........................................................................................................................................
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2 ........................................................................................................................................
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(b) Fig. 1.3 shows the cell cycle in an onion cell.
G2
G1 S
cell
growth
G2 checkpoint
G1 checkpoint
mitosis
DNA
synthesis
cell
growth
Fig. 1.3
Mitosis in an onion cell occurs once in 24 hours and lasts for 80 minutes.
Metaphase takes approximately 6.5 minutes to complete.
Calculate the percentage of the cell cycle which is spent in metaphase.
Metaphase = ...................................................... % [2]
(c) There are two main checkpoints in the cell cycle, the G1 checkpoint and the G2 checkpoint.
Explain how each of the checkpoints can ensure the cell develops normally.
G1 .............................................................................................................................................
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G2 .............................................................................................................................................
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[2]
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(d) The cell cycle is controlled by proteins. These proteins can initiate apoptosis.
Describe the sequence of events that occurs during apoptosis.
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2 Lenticels appear as small brown patches on the surface of some fruit.
A researcher wanted to investigate if water availability affected the number of lenticels on the
surface of apples.
They chose nine apple trees of one variety and watered each tree with a specific volume of water
every day for twelve weeks.
After twelve weeks they counted the total number of lenticels that developed on the surface of
one apple from each tree.
This was repeated with a second variety of apple.
Fig. 2.1 shows the number of lenticels found on the surface of the two varieties of apple.
100
0
200
400
600
800
1000
1200
200 300 400 500 600 700 800 900
Volume of water added to the tree (cm3)
Number
of lenticels
Variety 1 Variety 2
Fig. 2.1
(a) (i) Using only Fig. 2.1, what conclusions can be drawn about the effect of water availability
on lenticel number for these two varieties of apple?
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Version | LATEST 2022 |
Release date | 2022-07-19 |
Included files | |
Authors | Qwivy.com |
Pages | 24 |
Language | English |
Tags | OCR AS LEVEL BIOLOGY B Advancing Biology H022/02 Biology in Depth |
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