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*JUN207402101*

IB/M/Jun20/E16 7402/1

For Examiner’s Use

Question Mark

1

2

3

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8

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10

TOTAL

Thursday 4 June 2020 Morning Time allowed: 2 hours

Materials

For this paper you must have:

• a ruler with millimetre measurements

• a scientific calculator.

Instructions

• Use black ink or black ball-point pen.

• Fill in the boxes at the top of this page.

• Answer all questions.

• You must answer the questions in the spaces provided. Do not write

outside the box around each page or on blank pages.

• If you need extra space for your answer(s), use the lined pages at the end of

this book. Write the question number against your answer(s).

• Show all your working.

• Do all rough work in this book. Cross through any work you do not want

to be marked.

Information

• The marks for the questions are shown in brackets.

• The maximum mark for this paper is 91.

Please write clearly in block capitals.

Centre number Candidate number

Surname

Forename(s)

Candidate signature

I declare this is my own work.

A-level

BIOLOGY

Paper 1

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*02*

IB/M/Jun20/7402/1

Do not write

outside the

Answer all questions in the spaces provided. box

0 1 Figure 1 shows a cell from the lining of the ileum specialised for absorption of

products of digestion.

SGLT1 is a carrier protein found in the cell-surface membrane of this cell, it transports

glucose and sodium ions (Na+) into the cell.

Figure 1

0 1 . 1 The action of the carrier protein X in Figure 1 is linked to a membrane-bound ATP

hydrolase enzyme.

Explain the function of this ATP hydrolase.

[2 marks]

0 1 . 2 The movement of Na+ out of the cell allows the absorption of glucose into the

cell lining the ileum.

Explain how.

[2 marks]

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*03*

Turn over ►

IB/M/Jun20/7402/1

Do not write

outside the

box 0 1 . 3 Describe and explain two features you would expect to find in a cell specialised for

absorption.

[2 marks]

1

2

Question 1 continues on the next page

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