13: Photosynthesis 1 (Biochemistry)
Task 1: Read chapter 13 of Cambridge textbook (page 331-343)
Task 2: In your notes define the following terms:
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Chlorophyll
Stroma
Lamellae
Thylakoid membrane
Thylakoid space
Absorption spectrum
Task 3: Complete questions 1-5 from Cambridge textbook (page 334-336)
Task 4: Complete exercise 13.2 from Cambridge workbook (page 180)
Task 5: Complete the following questions:
The diagrams below represent chromatograms of photosynthetic pigments from two
species: Fucus, which is a brown alga, and a spinach plant.
Questions
1 Calculate Rf values for:
a chlorophyll c
(1 mark)
b beta carotene
(1 mark)
c
chlorophyll a
(1 mark)
d chlorophyll b.
(1 mark)
2 Suggest which two pigments share the greatest similarity in chemical properties.
Explain your answer.
(3 marks)
3 Calculate the range of Rf values exhibited by the xanthophyll pigments.
(2 marks)
4 What do the chromatograms indicate about the photosystems of the two species, and
how does this explain the colour of the organisms?
(4 marks)
5 Explain the importance to photosynthesis in both species of possessing photosystems
with several pigments.
(3 marks)
Task 6: Complete the following exam question
Q2.
Chloroplasts are involved in both the light-dependent reactions and light-independent reactions of
photosynthesis.
(a) Which row of the table shows where the light-dependent reactions and light-independent reactions take
place?
(1)
(b) The diagram shows the outline of a chloroplast.
Draw three labelled features on this diagram that are found in a chloroplast, other than the stroma and the
thylakoid membranes.
(3)
(c) An absorption spectrum shows how much light is absorbed by chloroplasts at different wavelengths of light.
The table shows the colour of light at four wavelengths.
Which wavelength of light is absorbed the least by chloroplasts?
(1)
A
460 nm
B
520 nm
C
600 nm
D
680 nm
(d) State what is meant by the term action spectrum.
(1)
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(e) Chloroplast pigments can be separated and then identified by their Rf values.
(i) Which process can be used to separate chloroplast pigments?
(1)
A
B
C
D
chromatography
dendrochronology
osmosis
PCR
(ii) The diagram shows separated chloroplast pigments, J and K.
What is the Rf value for chloroplast pigment J?
(1)
A
B
C
D
0.625
0.800
0.830
1.714
(Total for question = 8 marks)
Task 7: Define the following terms
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Photosystem
Light-dependent stage
Light-independent stage
Photolysis
Photophosphorylation
NADP
Cyclic photophosphorylation
Photoactivation
Non-cyclic photophosphorylation
Ribulose bisphosphate
Rubisco
Glycerate-3-phosphate
Triose phosphate
Task 8: Complete questions 6 and 7 in the Cambridge textbook (page 337-338)
Task 9: Complete questions 8 and 9 in the Cambridge textbook (page 339)
Task 10: Complete exercise 13.1 in Cambridge workbook (page 176)
Task 11: Complete exercise 13.4 in Cambridge workbook (page187)
Task 12: Complete summary questions 2, 4 and 5 in Cambridge workbook (page 191-193)
Task 13: Use the blank knowledge organiser to quiz on the light-dependent and light-independent stages of
photosynthesis
Task 14: Complete the following exam questions