1

SAT Questions By Level 9C, 9D Plants,Photosynthesis

Commentary Previously set questions are heavily loaded towards Levels 6 and 7, and often include testing of other topic areas, eg Cell Specialisations and Ecological Relationships.

Level 4

1. Bindweed is a plant that grows tightly around other plants. The drawing below shows bindweed growing around a rose bush.

(a) Complete the sentences below. Choose from the words in the list.

air light support water minerals

(i) Bindweed grows as high as possible on the rose bush so that the bindweed can get as much .................................... as possible.

1 mark

(ii) Bindweed grows around the rose bush because the rose bush provides ....................................... for the bindweed.

1 mark

(b) A gardener cut through the stem of the bindweed at X. Two days later the bindweed above X was dead.

Why did the bindweed die? Tick the correct box.

no air no light

no warmth no water

1 mark

2

(c) The gardener adds fertiliser to the soil to help her rose bushes to

grow well.

What do plants get from the fertiliser? Tick the correct box.

acids minerals

sugars vitamins

1 mark

(d) Plant roots have root hairs.

Which diagram shows a root hair? Tick the correct box.

not to scale

1 mark

maximum 5 marks

3

2. The drawing shows a plant called Tillandsia.

(a) (i) The leaves of this plant absorb light. Why do plants need light?

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1 mark

(ii) Tillandsia plants grow on the high branches of trees in rain forests.

not to scale

These plants cannot grow well on the lowest branches. Explain why.

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1 mark

4

(b) Tillandsia plants do not have root hairs on their roots.

What two substances do most plants absorb through their root hairs?

1. ................................................................................................................

2. ................................................................................................................

2 marks

(c) Which diagram below shows a root hair? Tick the correct box.

A B

C D

not to scale

1 mark

Maximum 5 marks

5

Level 5 3. Every year thousands of trees are cut down in forests.

(a) Mammals and birds are two groups of animals that live in forests.

Give two reasons why fewer mammals and birds can survive after trees have been cut down.

1 ......................................................................................................................

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1 mark

2 ......................................................................................................................

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1 mark

(b) Many small plants grow in the clearings left after trees are cut down.

Explain why small plants are able to grow well after the trees have been cut down.

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2 marks

6

(c) In some forests, small branches are left on the ground.

Fungi and bacteria feed on these branches and release minerals, such as nitrates, back into the soil.

Why is it important that the minerals are released back into the soil?

...............................................................................................................

...............................................................................................................

1 mark (d) A label was printed on the back of a birthday card.

The paper for this card was

made from wood taken from

sustainable forests.

In sustainable forests, new trees are planted to replace trees that are cut down.

Give two reasons why it is important to replace forest trees that are cut down.

1 ......................................................................................................................

1 mark

2.........................................................................................................................

1 mark

maximum 7 marks

7

4. Plants take in water from the soil. Lisa did an experiment to find out if there is anything else in soil that plants need for growth.

The diagrams below show the results of Lisa’s experiment.

Lisa made the clear, brown solution in flask B by shaking a mixture of soil and water and then separating the solution from the soil particles.

(a) How could Lisa separate the brown solution from the soil particles?

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1 mark

(b) Explain why Lisa grew one plant in distilled water.

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1 mark

(c) (i) What type of substance, dissolved in the water in flask B, is used by the plant for growth?

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1 mark

(ii) How are roots adapted for taking in water?

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1 mark

8

(d) Lisa set up a second experiment using three similar plants. The solution in flasks C, D and E was the same. She put all three flasks in a sunny position. The diagrams below show the results of Lisa’s second experiment.

The plant in flask C was the only one which grew well in this experiment. Explain why.

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1 mark

Maximum 5 marks

9

5. The drawing shows an experiment to investigate photosynthesis in

weed from a pond.

test-tube gas

water

pond weedplasticine

funnel

beaker

Bubbles of gas produced during photosynthesis were given off from the pond weed and collected in the test tube.

(a) Name the gas given off in photosynthesis

......................................................................................................................

1 mark

(b) What two substances are taken in by the plant and used for photosynthesis?

1. ..................................................................................................................

2. ..................................................................................................................

2 marks

Light of different intensities was shone onto the pond weed. The number of gas bubbles given off in one minute at each light intensity was counted. The results are shown in the graph.

number ofbubbles perminute

light intensity

A B C D E

10

(c) Which letter on the horizontal axis shows the light intensity at which the rate of photosynthesis first reaches its maximum?

............................................................

1 mark Blue, green and red light were then shone, in turn, onto the pond

weed. The number of bubbles of the gas given off in one minute was counted. The results are shown in the table.

colour of light number of

bubbles in one

minute

blue 85

green 10

red 68

The leaves of the pond weed contain a green pigment which absorbs light for photosynthesis

(d) (i) Name this pigment.

.............................................................................................................

1 mark

(ii) Using the information in the table, tick a box by one colour of light which is strongly absorbed by the pigment.

blue

green

red

1 mark

(e) Sugar is also produced during photosynthesis.

Give two ways in which the plant uses sugar.

1. .........................................................................................................

2. ..........................................................................................................

2 marks

Maximum 8 marks

11

Level 6 6. Joe bought a potted plant. He kept it well watered but some of the leaves

turned yellow.

Joe thought that the plant did not have enough light for photosynthesis. He moved the plant closer to the window but more leaves turned yellow.

(a) He then thought that the plant did not have enough minerals.

The table below gives information about minerals.

mineral why the mineral is needed

magnesium to make chlorophyll

nitrogen to make protein

phosphorus to grow and transfer energy

potassium to make fruit

(i) Joe’s plant did not have enough of one of the minerals in the table. Use the information in the table to suggest which mineral this was.

.............................................................

1 mark

(ii) A plant growing in a pot is more likely to be affected by a shortage of minerals than a plant growing in a garden. Give the reason for this.

...............................................................................................................

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1 mark

12

(b) Joe bought some fertiliser for his plant.

The names and formulae of four different fertilisers are shown below.

Easy grow

NH NO

Epsom Salts

MgSO

Saltpetre

KNO

Superphosphate

Ca(H PO )4 4 43 3 2

A B C D

2

(i) Give the letter of one box of fertiliser, A, B, C or D, that would provide each of the minerals in the table below. Write the letters in the table.

mineral letter of fertiliser

magnesium

nitrogen

phosphorus

potassium

3 marks

(ii) Easy Grow is ammonium nitrate, NH4NO3.

How many different elements are present in ammonium nitrate?

.............

1 mark

(iii) How many atoms are present in the formula of ammonium nitrate?

.............

1 mark

maximum 7 marks

13

7. Suzi investigated how temperature affects the number of bubbles

produced by waterweed in one minute.

She set up the experiment as shown below.

When the temperature of the water was 10°C the waterweed did not produce bubbles.

(a) Suzi increased the temperature of the water in the water-bath to 20°C. The waterweed started to produce bubbles. She waited two minutes before starting to count the bubbles.

Explain why she waited for two minutes before she started to count the bubbles.

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1 mark

14

(b) Suzi counted the number of bubbles produced at six different

temperatures.

Her results are shown on the graph below.

20

15

10

5

00 10 20 30 40 50 60 70

temperature of water-bath (ºC)

number ofbubblesproduced(per minute)

A

B

C D

E

F

(i) Draw a smooth curve on the graph.

1 mark

(ii) Use your curve to find the temperature of water which produced the most bubbles per minute.

..............°C

1 mark

(c) Suzi predicted that the higher the temperature the more bubbles would be produced.

Which points on the graph support Suzi’s prediction?

...............................................................................................................

1 mark

(d) Suzi’s data does not show clearly the exact temperature at which most bubbles were produced.

How could she improve the data she collects to find this temperature?

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1 mark

maximum 5 marks

15

8. Some pupils grew carrot plants for a project on plant growth. At the end of

the summer they dug up the carrots. The drawings show two of their carrots.

(a) Plant A came from a part of the garden which was covered with weeds. Plant B came from a part of the garden which had been kept free of weeds.

Suggest two ways in which the weeds may have stopped plant A from growing as large and healthy as plant B.

1. ..................................................................................................................

......................................................................................................................

2. ..................................................................................................................

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2 marks

16

(b) Explain why the pupils’ plants produced bigger roots when they

received more light.

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3 marks

Maximum 5 marks

17

Level 7

9. The table shows how hydrogencarbonate indicator solution changes colour when the concentration of carbon dioxide in it changes.

concentration of carbon dioxide

colour change

increases orange to yellow

decreases orange to purple

Sunil set up the experiment shown below and put both test-tubes on a window-sill.

Use information in the table to help you answer the questions below.

(a) The indicator in test-tube A changed from orange to yellow.

(i) What process, in the cells of the maggots, caused this colour change?

.............................................................................................................

1 mark

(ii) Explain what happens in this process to cause the colour change.

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1 mark

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(b) The indicator in test-tube B changed from orange to purple.

(i) What process, in the cells of the leaves, caused this colour change?

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1 mark

(ii) Explain what happens in this process to cause the colour change.

.............................................................................................................

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1 mark

(c) Sunil then put two fresh leaves into test-tube C containing 30 cm3 of orange hydrogencarbonate indicator. He added some maggots on a piece of wire mesh as shown below. He put the test-tube on a window-sill.

The indicator remained orange. Explain why.

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1 mark

maximum 5 marks

19

10. The drawing shows a bluebell plant. The plant grows from an

underground stem called a bulb. Each year new leaves and flowers grow from the bulb.

(a) Describe the process by which glucose is made in the leaves.

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3 marks

(b) Many plants make starch from glucose. What group of nutrients do both glucose and starch belong to?

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1 mark

20

(c) In the sixteenth century bluebell bulbs were dug up to obtain a starch-

like substance that was used to make collars stiff.

(i) Digging up bluebell bulbs has caused a decrease in the number of bluebells growing in Britain. It is now against the law to dig up bluebells.

Suggest one other environmental reason why the number of bluebell plants has decreased in Britain.

.............................................................................................................

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1 mark

(ii) Every 10 years the trees and bushes in some bluebell woods are cut down to ground level.

What effect does this have on the number of bluebells in the woods? Explain your answer.

.............................................................................................................

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1 mark

Maximum 6 marks

21

11. In the seventeenth century a Belgian scientist, Van Helmont, planted a

young willow tree in a tub of dry soil. During the next five years he watered the plant with rain water but he did not add anything else to the tub.

at the start five years later

not to scale

After five years Van Helmont removed the willow tree from the tub and weighed the tree. He also dried and weighed the soil. Results from Van Helmont’s experiment are shown in the table.

at the start

five years later

mass of willowtree, in kg

mass of driedsoil, in kg

2.3

76.7

90.6

90.5

(a) Van Helmont concluded that the increase in the mass of the willow tree was due only to a gain in water.

(i) What two pieces of evidence did Van Helmont use to reach his conclusion?

…………………………………………………………………………………

…………………………………………………………………………………

…………………………………………………………………………………

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2 marks

(ii) We now know that Van Helmont’s conclusion is not correct. Explain why the mass of the willow tree increased by such a large amount.

…………………………………………………………………………

…………………………………………………………………………

2 marks

(b) Van Helmont believed that a plant would always grow faster if it was given more water. We now know that this is not true. Give two environmental conditions which can slow down the growth of a plant, even when it has plenty of water.

1. …….……………………………………………………………………

2. …….……………………………………………………………………

……….………………………………………………………………………

2 marks

(c) The fresh mass of a plant includes water. To measure plant growth accurately, scientists calculate the increase in the dry mass rather than the increase in the fresh mass of a plant.

Why is finding the increase in fresh mass not a reliable way to measure plant growth?

……….………………………………………………………………………………

……….………………………………………………………………………………

……….………………………………………………………………………………

1 mark

Maximum 7 marks

23

12. Mango trees are grown in hot, dry countries where the soil can be hard

and tightly compacted. Farmers water the mango trees by spraying water onto the soil around them.

(a) (i) Only a small amount of the water actually reaches the roots of the trees. Suggest one reason why.

.............................................................................................................

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1 mark

(ii) Suggest one other reason why mango trees do not grow well in soil which is hard and tightly compacted.

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1 mark

(b) Give two reasons why mango trees and other plants need water.

1. .................................................................................................................

.....................................................................................................................

2. .................................................................................................................

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2 marks

24

(c) There is a new method of watering mango trees. Trenches are dug between the trees and filled with small pieces of rock. Plastic pipes with small holes in them are placed on top of the pieces of rock and water is pumped along the pipes. Mango trees watered by this method produce 15% more fruit.

(i) Suggest one reason why pieces of rock are placed in the trenches under the pipes.

.............................................................................................................

.............................................................................................................

1 mark

(ii) With the new method, farmers can also add nitrates to the water in the pipes. Give one reason why plants need compounds which contain nitrogen.

.............................................................................................................

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1 mark

Maximum 6 marks

25

13. Plant cells use carbon dioxide in photosynthesis. Graph A below shows how the amount of carbon dioxide a tree takes in each day varies over one year.

amount ofcarbondioxide

winter spring summer autumntime of year

graph A

graph B

(a) (i) Give two reasons why photosynthesis occurs most rapidly in the summer.

1 .........................................................................................................

2 .........................................................................................................

2 marks

(ii) Name the two substances produced in photosynthesis.

............................................ and ..............................................

2 marks

(b) Trees which lose all their leaves in the autumn are described as deciduous. How can you tell from graph A that the tree being investigated is deciduous?

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1 mark

26

(c) Graph B above shows how the amount of carbon dioxide which

the tree gives out each day varies over one year.

What is the name of the process in the tree which produces carbon dioxide?

....................................................................................................................

1 mark

Maximum 6 marks