Surname
Centre
No.
Initial(s)
Paper Reference (complete below)
H
Candidate
No.
1H
Signature
Paper Reference(s)
5016H/1H
5028H/1H
Edexcel GCSE
Additional Science (5016H)
Biology (5028H)
Team Leader’s use only
Question Leave
Number Blank
B2 – Topics 1 to 4
Higher Tier
Thursday 5 June 2008 – Morning
Time: 30 minutes
Materials required for examination
Calculator
Examiner’s use only
Items included with question papers
Nil
1
2
3
4
5
6
Instructions to Candidates
In the boxes above, write your centre number, candidate number, your surname, initial(s) and
signature, and complete the paper reference.
Check that you have the correct question paper.
Answer ALL the questions. Write your answers in the spaces provided in this question paper.
Do not use pencil. Use blue or black ink.
Show all stages in any calculations and state the units. Calculators may be used.
Include diagrams in your answers where these are helpful.
Information for Candidates
The marks for individual questions and the parts of questions are shown in round brackets: e.g. (2).
There are 6 questions in this question paper. The total mark for this paper is 30.
There are 8 pages in this question paper. Any blank pages are indicated.
Advice to Candidates
You are reminded of the importance of clear English and careful presentation in your answers.
Total
This publication may be reproduced only in accordance with
Edexcel Limited copyright policy.
©2008 Edexcel Limited.
Printer’s Log. No.
N33019A
W850/R1536/57570 6/6/6/3/28,000
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*N33019A0108*
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1.
The diagram shows a palisade cell from a leaf.
X
nucleus
(a) Name the structure marked X and explain its function.
Name .............................................................................................................................
Function ........................................................................................................................
.......................................................................................................................................
(2)
If we are to live on Mars in the future we may have to live in a biosphere similar to this
one.
(b) Suggest two reasons why it is necessary to have plants in the biosphere.
1 ....................................................................................................................................
2 ....................................................................................................................................
(2)
(c) The distance from the Sun to Mars is greater than the distance from the Sun to
Earth.
Explain one problem that the extra distance from the Sun may cause for the plants in
a biosphere on Mars.
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
(2)
(Total 6 marks)
2
*N33019A0208*
Q1
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blank
2.
This newspaper article on termination of pregnancies is from 2005.
In 1990 the Human Fertilisation and Embryology Act set the
standard legal limit for termination of pregnancies at 24
weeks.
Today, a group of MPs promised to cut the legal limit for
termination of pregnancies to 20 weeks.
(a) Suggest why many people support this change to reduce the limit for most termination
of pregnancies from 24 to 20 weeks.
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
(2)
(b) State one reason why a termination of pregnancy may still be legal after the fetus is
24 weeks old.
.......................................................................................................................................
.......................................................................................................................................
(1)
(c) Why do some groups of people think that termination of pregnancies should never be
allowed?
.......................................................................................................................................
.......................................................................................................................................
(1)
Q2
(Total 4 marks)
*N33019A0308*
3
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3.
The diagram shows a section of DNA
Complete these sentences about DNA.
DNA contains the code for making .................................
The DNA molecule is two strands coiled together to form a double .................................
The strands are linked by a series of paired .................................
Adenine always pairs with thymine and cytosine always pairs with .................................
(Total 4 marks)
4
*N33019A0408*
Q3
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4.
The diagram shows an alveolus and a capillary.
deoxygenated
blood
oxygenated
blood
air sac
red blood cell
CO2 O2
capillary
(a) Explain how exercise increases the amount of gas exchanged in the alveolus (lung
surface).
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
(3)
(b) How do muscle cells react if they are not supplied with enough oxygen for their
energy needs?
.......................................................................................................................................
.......................................................................................................................................
(1)
Q4
(Total 4 marks)
*N33019A0508*
5
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5.
In natural populations, 98% of African elephants develop tusks.
Tusks are a source of ivory which has been used to make valuable ornaments.
The table shows how the number of elephants and the percentage of elephants without
tusks has changed in one area of Africa.
year
number of elephants
percentage of elephants
without tusks
1967
3000
1.4
1977
3000
1.5
1987
2000
2.7
1997
540
16.0
2007
780
15.4
(a) Suggest how human activity may have caused the change in the percentage of
elephants without tusks up to 1997.
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
(2)
6
*N33019A0608*
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(b) Since 1997, the elephants in this area of Africa have been protected and their numbers
have begun to increase.
Suggest two possible consequences to the area of an increasing elephant population.
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
(2)
Q5
(Total 4 marks)
*N33019A0708*
7
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blank
6.
The two types of cell division are mitosis and meiosis.
(a) Complete the table below by writing yes or no in the boxes.
Do not leave any boxes blank.
part of process
mitosis
meiosis
produces 2 daughter cells
DNA replicates
produces gametes
daughter cells are
genetically identical
(4)
(b) State what is meant by the ‘Hayflick limit’, and explain how this limit relates to cell
division in humans.
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
(4)
(Total 8 marks)
TOTAL FOR PAPER: 30 MARKS
END
8
*N33019A0808*
Q6