4 Transport across cell membranes
AQA Biology Exam-style questions
1 Figure 1 shows the structure of part of the cell-surface membrane of an
animal cell.
Figure 1
a Name the structures labelled A and B.
A ....................................................
B .................................................... (2 marks)
b Describe the function of the structure labelled C.
(2 marks)
c The phospholipids in the diagram are orientated in a particular way. Explain why.
(3 marks)
2 a Give two differences between facilitated diffusion and active transport.
(2 marks)
A biologist placed red blood cells in a buffer solution containing glucose.
They investigated the effect of changing the concentration of glucose in the
buffer solution. Figure 2 shows the biologist’s results.
© Oxford University Press 2015 www.oxfordsecondary.co.uk/acknowledgements
This resource sheet may have been changed from the original 1
, 4 Transport across cell membranes
AQA Biology Exam-style questions
Figure 2
a i Using evidence from the graph, suggest how glucose is entering the red
blood cells.
(2 marks)
i Explain the shape of the curve above a glucose concentration of
30#mmol#dm−3.
(2 marks)
b i A buffer solution was used in this investigation. Explain why.
(2 marks)
i Suggest the pH value of the buffer used.
(1 mark)
3 Students carried out an experiment into the effect of temperature on the permeability of beetroot
cells. Beetroot cells contain a pigment which gives beetroots their red–purple colour.
This is the procedure the students followed:
cut cylinders of beetroot with a cork borer
cut the cylinders into slices 5mm thick
wash the slices in clean water until no more colour appears
© Oxford University Press 2015 www.oxfordsecondary.co.uk/acknowledgements
This resource sheet may have been changed from the original 2
AQA Biology Exam-style questions
1 Figure 1 shows the structure of part of the cell-surface membrane of an
animal cell.
Figure 1
a Name the structures labelled A and B.
A ....................................................
B .................................................... (2 marks)
b Describe the function of the structure labelled C.
(2 marks)
c The phospholipids in the diagram are orientated in a particular way. Explain why.
(3 marks)
2 a Give two differences between facilitated diffusion and active transport.
(2 marks)
A biologist placed red blood cells in a buffer solution containing glucose.
They investigated the effect of changing the concentration of glucose in the
buffer solution. Figure 2 shows the biologist’s results.
© Oxford University Press 2015 www.oxfordsecondary.co.uk/acknowledgements
This resource sheet may have been changed from the original 1
, 4 Transport across cell membranes
AQA Biology Exam-style questions
Figure 2
a i Using evidence from the graph, suggest how glucose is entering the red
blood cells.
(2 marks)
i Explain the shape of the curve above a glucose concentration of
30#mmol#dm−3.
(2 marks)
b i A buffer solution was used in this investigation. Explain why.
(2 marks)
i Suggest the pH value of the buffer used.
(1 mark)
3 Students carried out an experiment into the effect of temperature on the permeability of beetroot
cells. Beetroot cells contain a pigment which gives beetroots their red–purple colour.
This is the procedure the students followed:
cut cylinders of beetroot with a cork borer
cut the cylinders into slices 5mm thick
wash the slices in clean water until no more colour appears
© Oxford University Press 2015 www.oxfordsecondary.co.uk/acknowledgements
This resource sheet may have been changed from the original 2
