1. Answers should be written in continuous prose. Credit will be given for biological accuracy; the
organisation and presentation of the information and the way in which the answer is expressed.
Read the following passage.
Photosynthesis takes place in the chloroplasts. These are disc-shaped organelles surrounded by
an outer envelope consisting of two layers of membrane. Inside, there are further membranes
which are arranged in stacks called grana. Surrounding these is the stroma. Chlorophyll and
other light- capturing pigments are found on the membranes of the grana and it is here that the
light-dependent reaction takes place. This generates the ATP and reduced NADP which are used
in the light-independent reaction in the stroma.
(a) (i) Describe the way in which ATP and reduced NADP are produced in the light-
dependent reaction of photosynthesis.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(5)
(ii) Explain how ATP and reduced NADP are used in the light-independent reaction of
photosynthesis.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(4)
Sir George Monoux Sixth Form College 1
, (b) Using the information in the passage, describe how the structure of a chloroplast is
adapted to its function in photosynthesis.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(3)
(Total 12 marks)
2. (a) The diagram summarises the light-independent reaction of photosynthesis.
C a rb o n d io x id e ATP A D P + Pi
RuB P G P T rio se p h o s p h a te H exose
A D P
R educed N A D P
N A D P
ATP
(i) Complete the four boxes to show the number of carbon atoms in a molecule of each
substance.
(1)
(ii) Where in the chloroplast does the light-independent reaction take place?
...........................................................................................................................
(1)
(iii) Explain why the amount of GP increases after a photosynthesising plant has been in
darkness for a short time.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
Sir George Monoux Sixth Form College 2
, (b) Describe the role of water in the light-dependent reaction of photosynthesis.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
(Total 6 marks)
3. The island of Surtsey was formed in 1963 by a series of volcanic eruptions. Biologists have
studied the colonisation of this new island by plants and animals.
(a) The graph shows the number of species of plants found on the island each year for the
first seven years of its existence.
16
14
12
10
N um ber
o f s p e c ie s 8
6
4
2
0
1963 1964 1965 1966 1967 1968 1969 1970
Y ear
The development of the plant community on Surtsey illustrates the process of succession.
Explain why:
(i) very few species could grow on the island in the first few years after it was formed;
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(1)
Sir George Monoux Sixth Form College 3
, (ii) once some plants were growing, the rate at which new species could establish
themselves increased rapidly.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
(b) Animals also colonised Surtsey. One conclusion drawn from studying them was that
particular species of animals found here had broader ecological niches than they did on
the nearby mainland. Suggest why.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(1)
(Total 4 marks)
4. Answers should be written in continuous prose. Credit will be given for biological accuracy, the
organisation and presentation of the information and the way in which the answer is expressed.
Read the following passage.
The living state requires a constant input of energy, and the most fundamental difference
between animals and plants is the way they obtain their energy. Animals take in food - organic
compounds - and release chemical energy during respiration; green plants absorb light energy
from the sun, converting it to chemical energy in the process of photosynthesis.
Source. adapted from RIDGE.I.(ED), Plant Physiology (Hodder and Stoughton, 1991)
(a) Describe how plants absorb light energy from the sun and use this energy to produce
useful substances in the light-dependent stage of photosynthesis.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(5)
Sir George Monoux Sixth Form College 4
organisation and presentation of the information and the way in which the answer is expressed.
Read the following passage.
Photosynthesis takes place in the chloroplasts. These are disc-shaped organelles surrounded by
an outer envelope consisting of two layers of membrane. Inside, there are further membranes
which are arranged in stacks called grana. Surrounding these is the stroma. Chlorophyll and
other light- capturing pigments are found on the membranes of the grana and it is here that the
light-dependent reaction takes place. This generates the ATP and reduced NADP which are used
in the light-independent reaction in the stroma.
(a) (i) Describe the way in which ATP and reduced NADP are produced in the light-
dependent reaction of photosynthesis.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(5)
(ii) Explain how ATP and reduced NADP are used in the light-independent reaction of
photosynthesis.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(4)
Sir George Monoux Sixth Form College 1
, (b) Using the information in the passage, describe how the structure of a chloroplast is
adapted to its function in photosynthesis.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(3)
(Total 12 marks)
2. (a) The diagram summarises the light-independent reaction of photosynthesis.
C a rb o n d io x id e ATP A D P + Pi
RuB P G P T rio se p h o s p h a te H exose
A D P
R educed N A D P
N A D P
ATP
(i) Complete the four boxes to show the number of carbon atoms in a molecule of each
substance.
(1)
(ii) Where in the chloroplast does the light-independent reaction take place?
...........................................................................................................................
(1)
(iii) Explain why the amount of GP increases after a photosynthesising plant has been in
darkness for a short time.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
Sir George Monoux Sixth Form College 2
, (b) Describe the role of water in the light-dependent reaction of photosynthesis.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
(Total 6 marks)
3. The island of Surtsey was formed in 1963 by a series of volcanic eruptions. Biologists have
studied the colonisation of this new island by plants and animals.
(a) The graph shows the number of species of plants found on the island each year for the
first seven years of its existence.
16
14
12
10
N um ber
o f s p e c ie s 8
6
4
2
0
1963 1964 1965 1966 1967 1968 1969 1970
Y ear
The development of the plant community on Surtsey illustrates the process of succession.
Explain why:
(i) very few species could grow on the island in the first few years after it was formed;
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(1)
Sir George Monoux Sixth Form College 3
, (ii) once some plants were growing, the rate at which new species could establish
themselves increased rapidly.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
(b) Animals also colonised Surtsey. One conclusion drawn from studying them was that
particular species of animals found here had broader ecological niches than they did on
the nearby mainland. Suggest why.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(1)
(Total 4 marks)
4. Answers should be written in continuous prose. Credit will be given for biological accuracy, the
organisation and presentation of the information and the way in which the answer is expressed.
Read the following passage.
The living state requires a constant input of energy, and the most fundamental difference
between animals and plants is the way they obtain their energy. Animals take in food - organic
compounds - and release chemical energy during respiration; green plants absorb light energy
from the sun, converting it to chemical energy in the process of photosynthesis.
Source. adapted from RIDGE.I.(ED), Plant Physiology (Hodder and Stoughton, 1991)
(a) Describe how plants absorb light energy from the sun and use this energy to produce
useful substances in the light-dependent stage of photosynthesis.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(5)
Sir George Monoux Sixth Form College 4
