1

Exercise 1

1. The diagram below shows light striking a green leaf.

a) Arrow X shows light being absorbed. State the terms

used to describe what is happening to the light at Y and

Z. (1)

b) The diagram below represents the absorption of

different colours of light by a photosynthetic pigment.

(i) Name this pigment. (1)

(ii) State the role of the accessory pigments in

photosynthesis. (1)

(iii) Name an accessory pigment. (1)

(iv) Name the technique that can be used to separate

these pigments. (1)

2

2. The diagram shows a chloroplast from a palisade mesophyll cell.

a) Name regions P and Q. (2)

b) In which region of the chloroplast are chlorophyll

molecules located? (1)

c) When “chlorophyll” is separated and a diagram like the one drawn

below can be obtained.

A pigment can be identified from its Rf value which can be

calculated as follows:

Rf = distance travelled by pigment from origin

distance travelled by solvent from origin

Calculate the Rf values of pigments:

(i) 1 (1)

(ii) 3 (1)

3

GP (glycerate 3 - phosphate)

3. a) On Earth, the energy input from sunlight is around 2.0 X

1012 kilojoules per hectare per annum. The energy

captured by photosynthesising plants is around 2.0 X

1010kilojoules per hectare per annum. (A hectare is a

measurement of area).

What is the percentage efficiency of photosynthesis of

these plants? (1)

b) State the energy change that occurs during

photosynthesis. (1)

Total = 12

Exercise 2

1. In an investigation into the sequence of reactions that occur

in photosynthesis, unicellular green algae were kept in the dark

for 2 hours and then exposed to light for varying periods. After

each period of illumination an extract of the algal cells was

obtained. The chromatogram developed from these extracts

are shown below together with the length of period of illumination.

(i) From the chromatograms, state the sequence in which these

chemical compounds were formed. (1)

4

(ii) The Rf value of a compound can be calculated from a

chromatogram and then used to identify the compound. The

formula for calculating the Rf value is shown below.

Rf value = distance travelled by comound from origin

distance travelled by solvent from origin

From the chromatogram, using the formula, calculate the Rf

Value of glycine. (1)

2. a) Pigments that absorb light are found within leaf cells.

State the exact location of these pigments. (1)

b) Give one reason why plants often have more than one

photosynthetic pigment. (1)

c) The diagram contains information about light striking a leaf.

Apart from being absorbed or reflected, what can happen to

the light which strikes a leaf? (1)

d) The graph shows the absorption spectra of three

photosynthetic pigments. Pigments P and Q were extracted

from an aquatic plant whose leaves float on the water surface.

Pigment R was extracted from a species of photosynthetic algae

that lives in the water below the floating plant.

5

(i) Chose the wavelengths of light at which pigment P shows

greatest absorption.

A 425 – 450nm

B 450 – 475nm

C 525 – 550nm

D 625 – 650nm

E 650 – 675nm (1)

(ii) What are the two main colours of light which are used for

photosynthesis? (1)

(iii) From the information given in the graph, explain how the algae

from which pigment R was extracted are adapted to

photosynthesise in their environment. (1)

(iv) What element do plants need to make chlorophyll? (1)

(v) Explain the difference between the absorption spectrum and

the action spectrum. (2)

Total = 11

Exercise 3

1. The diagram below shows a chloroplast magnified twenty

thousand times.

a) (i) Name the stack of membranes labelled X. (1)

(ii) Apart from chlorophyll a or b, name two other pigments

that could be found at point X. (2)

(iii) State the benefit to plants of having these other

pigments. (1)

6

(iv) Name the region of the chloroplast where glucose is

produced. (1)

(v) State the two raw materials required for photosynthesis.(2)

b) Using the information given above, calculate the length of the

chloroplast in microns (µm). (1)

2. The diagram below shows part of the light dependent stage of

photosynthesis.

(i) Name this part of the light dependent stage. (1)

(ii) Name compound X. (1)

(iii) State the exact location of this part of the light

dependent stage. (1)

(iv) Name the two chemical compounds produced in the light

dependent stage that are needed for the carbon fixation

stage (Calvin cycle). (2)

Total = 13

Exercise 4

1. The diagram shows an outline of the stage in photosynthesis.

7

a) (i) Name the by-product produced by the light dependent

stage. (1)

(ii) Name products X and substance Y. (2)

(iii) State the number of carbon atoms in

1 RuBp (1)

2 GP (1)

b) (i) Describe the role of ATP in photosynthesis. (1)

(ii) Explain why hydrogen from the light dependent stage of

photosynthesis is needed by the Calvin cycle. (1)

2. The diagram below shows an outline of the Calvin cycle.

a) Name compounds K and L in the Calvin cycle above. (2)

b) (i) Name the structural compound N. (1)

(ii) Where in a plant cell is this compound found? (1)

c) The hydrogen required for the Calvin cycle comes from

the light-dependent stage of photosynthesis.

(i) Name the source of the hydrogen. (1)

(ii) Name the compound responsible for hydrogen

transfer to the Calvin cycle. (1)

8

(iii) Name one other product of the light-dependent

stage which is required for the Calvin cycle. (1)

3. a) Other than being absorbed for use in photosynthesis,

give two possible fates of the light energy that shines

onto the leaves of plants. (2)

b) Within which region of a chloroplast does the absorption

of light take place? (1)

Exercise 5

1. The graph below shows the relative

concentrations of glycerate

3-phosphate (GP) and ribulose 1, 5-biphosphate (RuBP) in a

chloroplast during changes in light and dark reactions.

(i) What evidence from the graph supports the statement that GP

can be converted to RuBP in light? (1)

(ii) Name the two chemical compounds produced in the light

dependent stage that are required for the conversion of GP to

RuBP. (2)

(iii) Other than being converted to RuBP, GP is also converted to a

6 carbon sugar. Name this 6 carbon sugar. (1)

(iv) Within which region of the chloroplast does the inter-conversion

of GP and RuBP occur? (1)

Total = 17

9

2. Copy and complete the table below by inserting the number of

carbon atoms present in each of the chemical compounds. Please

use a ruler.

Compound Number of carbon atoms

GP

RuBP

Glucose

3. The diagram below represents the light-dependent stage of

photosynthesis.

a) (i) Identify substances X, Y and Z. (3)

(ii) Which of these is a by-product of the process and diffuses

out of the cell? (1)

(iii) Which of these go on to play important roles at a later

stage in photosynthesis? (1)

b) (i) In which region of a chloroplast does the light-dependent

stage of photosynthesis occur? (1)

(ii) Oxygen is released as a by-product during the light-

dependent stage of photosynthesis. State the source of

this oxygen. (1)

4. The graph below shows the effect of light intensity of the rate

of photosynthesis at different temperatures.

(1)

10

Exe

rcis

e 6

1. The diagram below outlines the chemistry of photosynthesis.

a) Name compounds A and E. (2)

b) (i) Name reaction 2. (1)

(ii) State the exact location of reaction 2 (1)

c) State the function of NADP. (1)

2. The graph below shows the effects of varying light intensity,

carbon dioxide and temperature on the rate of photosynthesis

in a plant.

What is the limiting factor at point X on the graph. (1)

Total = 14

11

(i) At a light intensity of 60 kilolux, identify which factor, as shown

in the graph, has the greater effect in increasing the rate of

photosynthesis. (1)

(ii) Justify your answer to part (i). (1)

(iii) The rate of photosynthesis can be calculated by measuring a

change in dry mass with time.

State one other method that can be used to calculate the rate

photosynthesis. (1)

(iv) Within which region of the chloroplast does the absorption of

light take place? (1)

3. State the number of carbon atoms present in one molecule of

each substance.

(i) glucose

(ii) carbon dioxide

(iii) glycerate phosphate (GP)

(iv) Ribulose biphosphate (RuBP) (2)

4. Two groups of barley seeds were grown in different growth

mediums. The only difference was that Group B lacked

magnesium, Group A did not. At the end of three weeks, an

extract of photosynthetic pigments was made from the leaves

of each plant group. The absorption spectra below were obtained

from these extracts.

12

a) Name a technique that could be used to separate these

pigments. (1)

b) Explain the difference between the absorption in the blue and

red regions of the spectrum by these two groups of plants. (2)

c) Name a pigment which may account for the peak at X in the

absorption spectrum of the magnesium deficient group. (1)

Total = 15

Exercise 7

1. The diagram below shows a summary of the light stage of

photosynthesis.

a) (i) Desrcibe how hydrogen is produced in the light stage of

photosynthesis. (1)

(ii) Name the substance that transfers hydrogen to the

Calvin cycle. (1)

b) (i) Copy and complete the diagram below by inserting the

appropriate letter from the table into each box.

Light energy absorbed by

pigments

Hydrogen and ATP produced for

use in the Calvin cycle

13

(2)

(ii) Glucose can be converted into a storage carbohydrate.

Name this storage carbohydrate. (1)

2. The graph below shows the effect of increasing light intensity

on the rate of photosynthesis at different carbon dioxide

concentrations and temperatures.

a) Identify the factor limiting the rate of photosynthesis at point

Y on the graph. (1)

b) From the graph, identify the factor that has the greatest

effect in increasing the rate of photosynthesis at a light

intensity of 80 units. Justify your answer. (1)

3. (i) As well as chlorophyll, plants have other photosynthetic

pigments. State the benefit to plants of having these other

pigments. (1)

(ii) State the exact location of photosynthetic pigments

within a chloroplast. (1)

14

(iii) Name the metal element that plants require to

manufacture chlorophyll. (1)

(iv) Copy and complete the following sentence:

When light strikes a leaf, some is absorbed some is

______________ and the rest is _______________. (1)

(v) State the two main colours of light that are absorbed by

chlorophyll for use during photosynthesis. (1)

4. The diagram below summarises the process of photosynthesis in

a chloroplast.

(i) Name molecules X and Y. (2)

(ii) State the function of molecule Y. (1)

(ii) State the exact location of the light dependent stage within a

chloroplast. (1)

(iii) Name cycle Z. (1)

(iv) Name the cell wall component referred to in the diagram. (1)

5. The following sentences describe events in the carbon fixation

stage of photosynthesis. Copy and complete the sentences by

choosing one word in the brackets.

three

{

}

15

The carbon compound ribulose

five

carbon dioxide

biphosphate (RuBP) accepts .

hydrogen

Carbon dioxide three

is accepted by the

Hydrogen five

carbon compound glycerate phosphate (GP). (2)

}

{

{

{

}

}

Total = 20