Plant Structures and their functions - Questions Q1. A student is growing algae to make algal balls to investigate how light intensity affects photosynthesis.

A small culture of algae is added to a large bottle of distilled water.

Air is then bubbled through and the bottle is placed in front of a light source.

After 4 weeks, enough algae have grown for the student to make algal balls.

Figure 6 shows the apparatus used.

Figure 6

To make the algal balls, the algae are mixed with sodium alginate.

The student uses a syringe to add the mixture drop by drop into calcium chloride solution, which causes the algal balls to form.

Figure 7 shows this process.

Figure 7

(i) State why the algal balls need to be washed before being used. (1)

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(ii) State one relevant safety precaution that should be used when making the algal balls. (1)

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............................................................................................................................................. (Total for question = 2 marks)

Q2. Auxins are plant hormones. (i) Complete the sentence by putting a cross ( ) in the box next to your answer.

Auxins cause the shoot of a plant to grow towards light in a process called (1)

A negative gravitropism B negative phototropism C positive gravitropism D positive phototropism

(ii) Explain how auxins cause the shoot of a plant to grow towards light. (2)

.............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. Q3. Climacteric fruits are fruits that can ripen after they have been removed from the plant.

(i) Which plant hormone can be used to ripen climacteric fruit? (1)

A auxin B ethene C gibberellin D insulin

(ii) When climacteric fruits ripen, they release a gas during respiration.

Which gas is released by these fruits during respiration? (1)

A carbon dioxide B carbon monoxide C oxygen D nitrogen

(Total for question = 2 marks)

Q4. A scientist investigated the role of gibberellins in seed germination.

The scientist placed 20 cress seeds on agar jelly containing gibberellins.

The scientist counted the number of seeds that had germinated after 5 days.

Figure 10 shows the results.

Figure 10

State two commercial uses of gibberellins not including their role in germination. (2)

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

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

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Q5.

A student is growing algae to make algal balls to investigate how light intensity affects photosynthesis.

A small culture of algae is added to a large bottle of distilled water.

Air is then bubbled through and the bottle is placed in front of a light source.

After 4 weeks, enough algae have grown for the student to make algal balls.

Figure 6 shows the apparatus used.

Figure 6

The student placed some algal balls into each of five small glass bottles containing hydrogencarbonate indicator.

Each bottle was sealed with a lid and placed at a different distance from a light source.

Hydrogencarbonate indicator changes colour due to the amount of carbon dioxide in the solution.

The investigation was left for 50 minutes and the colour of the hydrogencarbonate solution was recorded.

Figure 8 shows this investigation.

Figure 8

(i) State two variables the student will need to control in this investigation. (2)

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

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(ii) At the start of the investigation the hydrogencarbonate indicator was red in colour. Figure 9 shows the colour of hydrogencarbonate indicator in solutions that have different pH.

Figure 9 Explain why the hydrogencarbonate indicator in the bottle nearest to the light source turned purple.

(3) .............................................................................................................................................

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............................................................................................................................................. (Total for question = 5 marks)

Q6. Auxins are plant hormones.

Ethylene (ethene) is a plant hormone that stimulates the ripening of fruit. The graph shows the effect of ethylene (ethene) concentration on the ripening of bananas after three days.

(i) Describe the effect of ethylene (ethene) on the ripening of bananas.

(1) .............................................................................................................................................. ..............................................................................................................................................

(ii) Explain which concentration of ethylene (ethene) a supermarket should use to be most cost effective when ripening bananas.

(2) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................

Q7. Auxins are plant hormones. * Fruit ripening is one use of plant hormones. Describe the other uses of plant hormones in crop production.

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.............................................................................................................................................. Q8. A scientist investigated the role of gibberellins in seed germination.

The scientist placed 20 cress seeds on agar jelly containing gibberellins.

The scientist counted the number of seeds that had germinated after 5 days.

Figure 10 shows the results.

Figure 10

(i) After germination, roots grow downwards and shoots grow upwards. Which row of the table is correct for the growth response shown by roots and shoots?

(1)

(ii) Explain how auxins can cause a plant root that is growing horizontally to grow downwards. (3)

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(Total for question = 4 marks)

Q9.

Genetic engineering can be used to produce plants that are resistant to herbicide. One herbicide works by preventing the activity of an enzyme. Some bacteria have a form of this enzyme that is not affected by the herbicide. (a) Suggest how genetic engineering can be used to produce plants resistant to this herbicide.

(3) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................

(b) This herbicide is sprayed onto the leaves of plants. Suggest which vessel could transport the herbicide from the leaf to other parts of the plant.

(1) ..............................................................................................................................................

(c) Fields of crops have weeds growing in them. In an investigation, crops resistant to a herbicide were grown in different fields. The crops were sprayed with different concentrations of the herbicide. The mass of the crops and weeds were recorded. The graph shows the results of this investigation.

(i) Describe the effects of the herbicide on the yield of weeds.

(2) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................

(ii) Complete the sentence by putting a cross ( ) in the box next to your answer. The most appropriate concentration of herbicide to use is

(1) A 10 arbitrary units B 30 arbitrary units C 40 arbitrary units D 50 arbitrary units (d) The table shows the number of species of weeds resistant to this herbicide from 1996 to 2004.

%%% Year 1996 1998 2000 2002 2004

Number of species of weeds resistant to this herbicide

1 2 3 5 8

(i) Describe the trend shown in the data. (1)

.............................................................................................................................................. .............................................................................................................................................. (ii) Suggest reasons for this trend.

(2) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................

(Total for Question is 10 marks) Q10. A student wanted to investigate the effect of light on the growth of cress seedlings.

The student had three pots of seedlings grown in different conditions.

Pot A was placed in a window with light from one direction only.

Pot B was placed in a cupboard with no light.

Pot C was placed with light from above.

Figure 8 shows the seedlings at the end of the investigation.

(a) (i) Label the pots of cress seedlings A, B and C. (2)

Figure 8 (ii) What is the response shown by the cress seedlings in Pot A?

(1)

A negative gravitropism B negative phototropism C positive gravitropism D positive phototropism

(iii) State the plant hormone that causes the cress seedlings to grow towards the light.

(1) .............................................................................................................................................

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(b) The student wanted to find out where the hormone that caused the response to directional light was found.

The student had two growing plant shoots and placed them both in a window with light coming from one direction. Describe a method the student could use to show that the hormone was found in the tip of the plant shoot.

(2) .............................................................................................................................................

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............................................................................................................................................. (Total for question = 6 marks)

Q11.

A gardener investigated the ability of four types of compost to hold water.

50cm3 of water was added to each type of compost.

Figure 6 shows the volume of water retained by four different types of compost.

Figure 6

(i) Calculate the percentage change in mass for compost B. (2)

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(ii) Explain which compost would be best to use for a pot containing strawberry plants to be grown during a hot summer.

(2) .............................................................................................................................................

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(iii) State one way to improve this investigation in order to compare the results without having to calculate the percentage change in mass.

(1) .............................................................................................................................................

............................................................................................................................................. (Total for question = 5 marks)

Q12.

A student is growing algae to make algal balls to investigate how light intensity affects photosynthesis.

A small culture of algae is added to a large bottle of distilled water.

Air is then bubbled through and the bottle is placed in front of a light source.

After 4 weeks, enough algae have grown for the student to make algal balls.

Figure 6 shows the apparatus used.

Figure 6

(i) Why is air bubbled through the distilled water containing the algae? (1)

A to provide oxygen for photosynthesis B to provide carbon dioxide for photosynthesis C to provide carbon dioxide for respiration

D to provide nitrogen for respiration (ii) Which part of an algal cell absorbs light energy to make glucose?

(1) A the ribosome in the chloroplast B the chlorophyll in the vacuole C the chlorophyll in the chloroplast D the ribosome in the nucleus

(Total for question = 2 marks)

Q13.

The diagrams show the underside of a leaf of a cowslip plant on a cool day and on a warm day.

(i) Complete the sentence by putting a cross ( ) in the box next to your answer. The parts of the leaf labelled X are

(1)

A stomata

B phloem vessels

C xylem vessels

D chloroplasts

(ii) Complete the following sentence.

(1) Carbon dioxide moves into the leaves through the parts labelled X by the process of ........................................................... .

(iii) Explain how changes to the guard cells on the warm day help the plant to survive.

(2) .............................................................................................................................................

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............................................................................................................................................. Q14.

The diagram shows three duckweed plants in a beaker of distilled water.

(i) Explain how the water moves into these plants.

(3) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. (ii) Salt was added to the water in the beaker to form a salt solution.

Explain how the salt solution would affect the movement of water into and out of the plant. (2)

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(iii) Complete the sentence by putting a cross ( ) in the box next to your answer. When the concentration of mineral ions in the soil is greater than in the root hair cell, mineral ions are transported into the root hair cells by

(1) A diffusion B osmosis C respiration D transpiration

Q15.

The graph suggests that the level of oxygen in the atmosphere was important for the evolution of many living organisms.

(i) How much oxygen was needed in the atmosphere for the evolution of land animals?

Put a cross ( ) in the box next to your answer. (1)

A 0.009%

B 0.09% C 0.9% D 9.0% (ii) Suggest how photosynthesis could have changed the gas content of the atmosphere.

(2) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. (iii) Suggest why such a high percentage of oxygen in the atmosphere was needed for large land animals to evolve.

(2) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. Q16.

The diagram shows a section through a leaf.

(i) Complete the sentence by putting a cross ( ) in the box next to your answer. The cell that will make the most glucose is

(1) A B C D

(ii) Describe how carbon dioxide enters the leaf. (2)

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.............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. (iii) Describe the process that takes place in the leaf to produce oxygen.

(3) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. Q17.

Plant growth substances

Photograph A shows the root of a plant when it was positioned horizontally.

The root was kept in the dark and left in this position.

Photograph B was taken three days later.

(a) (i) Complete the sentence by putting a cross ( ) in the box next to your answer.

The process that resulted in the type of root growth shown in photograph B is (1)

A negative gravitropism B negative phototropism C positive gravitropism D positive phototropism

(ii) Explain how this change in root growth has occurred. (3)

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............................................................................................................................................. (iii) Suggest the advantages to the plant of this response.

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(b) Rebecca and Andrew each set up an experiment to investigate the effect of light on plant shoots.

They also set up a control experiment. Rebecca placed a black cap over the tip of her plant shoot. Andrew removed the tip from his plant shoot, placed a thin block of jelly on top of the plant shoot and then replaced the tip. All three experiments were left for 24 hours.

(i) Suggest why Rebecca and Andrew set up a control experiment.

(1) .............................................................................................................................................

............................................................................................................................................. (ii) Explain the results of Rebecca's experiment and Andrew's experiment.

(3) .............................................................................................................................................

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............................................................................................................................................. (Total for question = 10 marks)

Q18.

Auxins are plant hormones. (a) (i) Complete the sentence by putting a cross ( ) in the box next to your answer.

Auxins cause the shoot of a plant to grow towards light in a process called (1)

A negative gravitropism B negative phototropism C positive gravitropism D positive phototropism

(ii) Explain how auxins cause the shoot of a plant to grow towards light. (2)

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Ethylene (ethene) is a plant hormone that stimulates the ripening of fruit. The graph shows the effect of ethylene (ethene) concentration on the ripening of bananas after three days.

(i) Describe the effect of ethylene (ethene) on the ripening of bananas.

(1) ..............................................................................................................................................

.............................................................................................................................................. (ii) Explain which concentration of ethylene (ethene) a supermarket should use to be most cost effective when ripening bananas.

(2) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................

*(c) Fruit ripening is one use of plant hormones. Describe the other uses of plant hormones in crop production.

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(Total for Question is 12 marks) Q19.

(a) The diagram shows a section through a leaf.

(i) Complete the sentence by putting a cross ( ) in the box next to your answer. The cell that will make the most glucose is

(1) A B C D

(ii) Describe how carbon dioxide enters the leaf. (2)

.............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. (iii) Describe the process that takes place in the leaf to produce oxygen.

(3) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................

(b) Root hair cells take in water and mineral ions from the soil. Draw one straight line from each substance to the process by which it enters the root hair cell.

(2)

(Total for Question is 8 marks)

Q20.

Root hair cells take in water and mineral ions from the soil. Draw one straight line from each substance to the process by which it enters the root hair cell.

(2)

Q21. Figure 9 shows a cross section through a pine leaf.

Figure 9

(i) Explain why the waxy cuticle is important for this pine leaf. (2)

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(ii) The transport vessels are labelled on Figure 9. Which row of the table is correct for the movement of sucrose through the plant?

(1)

(Total for question = 3 marks)

Q22. A student investigated the distribution of poppy plants in a park.

Figure 2 shows a sketch of the park and a diagram of a poppy plant.

Figure 2

The student placed a 1 m2 quadrat at 10 metre intervals between point A and point B and recorded the number of poppy plants in each quadrat.

(i) Name the technique the student used to study the distribution of poppy plants. (1)

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Figure 3 shows the number of poppy plants at 10 metre intervals from point A to point B.

Figure 3

(ii) Explain the effect of the woodland on the distribution of poppy plants. (3)

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(iii) Devise a plan, that uses a quadrat, to estimate the number of poppy plants in the field. (3)

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(Total for question = 7 marks)

Q23.

Transport and exchange of materials

Some students investigated water movement in plant cells.

They measured the mass of five pieces of potato.

Each piece of potato was put into a different concentration of salt solution.

After one hour the pieces of potato were dried and the mass of each was recorded.

The results are shown in the table.

(a) (i) Calculate the percentage change in the mass of the potato in the 20% salt solution.

(2)

........................................................... % (ii) Suggest why calculating a percentage change is more useful than calculating the change in mass in this investigation.

(1) .............................................................................................................................................

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(b) Mitosis occurs in plant cells during growth.

Describe the division of a cell by mitosis. (3)

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*(c) Explain how active transport and diffusion provide a plant with named substances it needs for growth.

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............................................................................................................................................. (Total for question = 12 marks)

Q24. Genetic engineering can be used to produce plants that are resistant to herbicide. One herbicide works by preventing the activity of an enzyme. Some bacteria have a form of this enzyme that is not affected by the herbicide. This herbicide is sprayed onto the leaves of plants. Suggest which vessel could transport the herbicide from the leaf to other parts of the plant.

(1) .............................................................................................................................................. Q25. A scientist investigated the role of gibberellins in seed germination.

The scientist placed 20 cress seeds on agar jelly containing gibberellins.

The scientist counted the number of seeds that had germinated after 5 days.

Figure 10 shows the results.

Figure 10

Explain how the scientist could use a control to improve this investigation. (3)

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............................................................................................................................................. (Total for question = 3 marks)

Q26.

The diagram shows three duckweed plants in a beaker of distilled water.

(a) (i) Explain how the water moves into these plants.

(3) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. (ii) Salt was added to the water in the beaker to form a salt solution.

Explain how the salt solution would affect the movement of water into and out of the plant. (2)

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(iii) Complete the sentence by putting a cross ( ) in the box next to your answer. When the concentration of mineral ions in the soil is greater than in the root hair cell, mineral ions are transported into the root hair cells by

(1) A diffusion B osmosis C respiration D transpiration *(b) Explain how water, glucose and mineral salts are transported through a plant.

(6) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................

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(Total for Question = 12 marks) Q27.

The diagram shows three duckweed plants in a beaker of distilled water.

* Explain how water, glucose and mineral salts are transported through a plant.

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