4BI1/1B 4SD0/1B Biology UNIT: 4BI1 Science (Double Award) 4SD0 PAPER: 1B

4BI1/1B 4SD0/1B Biology UNIT: 4BI1 Science (Double Award) 4SD0 PAPER: 1B
1 The table lists values that can be obtained in practical investigations.
(a) Complete the table by naming pieces of laboratory apparatus that can be used to
help obtain these values.
The first one has been done for you.
(4)
Value Apparatus
magnification of a red blood cell microscope
the heat produced by germinating seeds
surface area to volume ratio of a
potato cylinder
breathing rate of a human
volume of gas produced by yeast in
anaerobic respiration
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(b) The diagram shows a red blood cell viewed through a microscope.
(Source: © Artem_Graf/Shutterstock)
The actual width of this red blood cell is 8 µm.
The magnification of this red blood cell can be calculated using this formula.
magnification = width of cell in drawing
actual width of cell
Calculate the magnification of this red blood cell.
(2)
magnification = ..............................................................
(Total for Question 1 = 6 marks)
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2 The diagram shows the human heart with four blood vessels labeled A, B, C, and D.
A
B
 C
D
(a) (i) Which blood vessel brings oxygenated blood to the heart?
(1)
A B C D
(ii) Which blood vessel contains blood at the highest pressure?
(1)
A B C D
(b) (i) Draw a label line on the diagram to show the position of a semi‑lunar valve.
(1)
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(ii) Describe the function of the semi‑lunar valves.
(2)
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(c) In the heart of a foetus, the two upper chambers (atria) are linked by a hole so
that blood can pass between them.
(i) Explain why this hole is normally closed before the baby is born.