1.	The diagram below shows a cross section of a stem. What is the structure labelled Y and one of its functions?

	Structure Y	Function	
A.	phloem	storage of water and starch	
B.	xylem	mechanical support	
C.	phloem	gas exchange	
D.	xylem	transport of sugars	
(Total 1 mark)

2.	Plants develop brightly coloured flowers to attract animals. Which process is directly assisted by this adaptation?
A.	Seed dispersal
B.	Pollination
C.	Fertilization
D.	Germination
(Total 1 mark)

3.	Which structure is shown in the following image?
		
[Source: Ohio State University at Lima]
A.	A dicotyledon stem
B.	A monocotyledon stem
C.	A dicotyledon root
D.	A monocotyledon root
(Total 1 mark)

4.	What part of the human body is most similar in function to the spongy mesophyll layer in a leaf?
A.	Alveoli in the lungs
B.	Erythrocytes in the blood
C.	Villi in the small intestine
D.	Sweat glands in the skin
(Total 1 mark)

5.	Up to two additional marks are available for the construction of your answers.
(2)
	(a)	All organisms in an ecosystem are involved in the carbon cycle. Outline the roles of living organisms in the carbon cycle.
(8)
 
(b)	Explain how triose phosphate is produced and used in the chloroplasts of a plant.
(5)
 
(c)	Explain the conditions that are needed to allow a seed to germinate.
(5)
(Total 20 marks)

6.	Up to two additional marks are available for the construction of your answers.
(2)
	(a)	Outline the various stages of the cell cycle.
(4)
 
(b)	Describe the differences in the structures of dicotyledonous plants and monocotyledonous plants.
(5)
 
(c)	Define the term transpiration and explain the factors that can affect transpiration in a typical terrestrial plant.
(9)
(Total 20 marks)

7.	What are differences between monocotyledonous and dicotyledonous plants?

	Monocotyledonous	Dicotyledonous	
A.	parallel venation;
floral organs in multiples of 4 or 5	net-like venation;
floral organs in multiples of 3	
B.	net-like venation;
floral organs in multiples of 3	parallel venation;
floral organs in multiples of 4 or 5	
C.	net-like venation;
floral organs in multiples of 4 or 5	parallel venation;
floral organs in multiples of 3	
D.	parallel venation;
floral organs in multiples of 3	net-like venation;
floral organs in multiples of 4 or 5	
(Total 1 mark)

8.	What controls the flowering process in long-day plants?
A.	Pfr is converted by red light to Pr which acts as a promoter of flowering.
B.	Pr is converted by red light to Pfr which acts as an inhibitor of flowering.
C.	Pr is converted by red light to Pfr which acts as a promoter of flowering.
D.	Pfr is converted by red light to Pr which acts as an inhibitor of flowering.
(Total 1 mark)

9.	Which of the following are characteristics of monocotyledonous plants?
I.	Parallel venation of leaves
II.	Floral organs in multiples of four
III.	Fibrous adventitious roots
A.	I and II only
B.	I and III only
C.	II and III only
D.	I, II and III
(Total 1 mark)

10.	How do mineral ions in the soil move to the root through the soil?
A.	Osmosis
B.	Mass flow of water
C.	Translocation
D.	Through phloem
(Total 1 mark)

11.	Up to two additional marks are available for the construction of your answers.
(2)
	(a)	The main parts of growing plants are roots, stems and leaves. Draw a plan diagram to show the arrangement of tissues in the stem of a dicotyledonous plant.
(5)
 
(b)	Outline the adaptations of plant roots for absorption of mineral ions from the soil.
(5)
 
(c)	Photosynthesis and transpiration occur in leaves. Explain how temperature affects these processes.
(8)
(Total 20 marks)

12.	Up to two additional marks are available for the construction of your answers.
(2)
	(a)	Outline the structure of a ribosome.
(4)
 
(b)	Distinguish between fibrous and globular proteins with reference to one example of each protein type.
(6)
 
(c)	Explain the role of auxin in phototropism.
(8)
(Total 20 marks)

13.	How are fluids transported in the xylem and the phloem?

	Xylem	Phloem	
A.	away from the root only	towards the root only	
B.	towards the root only	away from the root only	
C.	away from and towards the root	towards the root only	
D.	away from the root only	away from and towards the root	
(Total 1 mark)

14.	How does phytochrome control flowering in plants?
A.	Pfr turns into Pr in the light, causing short-day plants to flower.
B.	Pr turns into Pfr in the light, causing long-day plants to flower.
C.	Pfr turns into Pr in the dark, causing long-day plants to flower.
D.	Pr turns into Pfr in the dark, causing short-day plants to flower.
(Total 1 mark)

15.	Gibberellin promotes both seed germination and plant growth. Researchers hypothesize that the gene GID1 in rice (Oryza sativa) codes for the production of a cell receptor for gibberellin.
The mutant variety gid1-1 for that gene leads to rice plants with a severe dwarf phenotype and infertile flowers when homozygous recessive. It is suspected that homozygous recessive gid1-1 plants fail to degrade the protein SLR1 which, when present, inhibits the action of gibberellin. The graphs show the action of gibberellin on the leaves and α-amylase activity of wild-type rice plants (WT) and their gid1-1 mutants.

	[Adapted by permission from Macmillan Ltd, Ueguchi-Tanaka, M et al. 2005.  “Gibberellin-insensitive dwarf1 encodes a soluble receptor for gibberellins”. Nature. Vol 437. Pp 693–698. Copyright (2005).]
 
(a)	(i)	State which variety of rice fails to respond to gibberellin treatment.
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(1)
 
(ii)	The activity of α-amylase was tested at successive concentrations of gibberellin.
Determine the increment in gibberellin concentration that produces the greatest change in α-amylase activity in wild-type rice plants (WT).
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(1)

(iii)	Outline the role of α-amylase during the germination of seeds.
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(1)
 
(b)	Discuss the consequence of crossing gid1-1 heterozygous rice plants amongst themselves for food production.
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(3)

	Most rice varieties are intolerant to sustained submergence under water and will usually die within a week. Researchers have hypothesized that the capacity to survive when submerged is related to the presence of three genes very close to each other on rice chromosome number 9; these genes were named Sub1A, Sub1B and Sub1C. The photograph below of part of a gel shows relative amounts of messenger RNA produced from these three genes by the submergence-intolerant variety, O. sativa japonica, and by the submergence-tolerant variety, O. sativa indica, at different times of a submergence period, followed by a recovery period out of water.

	[Adapted by permission from Macmillan Publishers Ltd, Xu et al. 2006. Nature. Vol 442. Pp 705–708. Copyright 2006. http://www.nature.com/]
 
(c)	(i)	Determine which gene produced the most mRNA on the first day of the submergence period for variety O. sativa japonica.
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(1)
 
(ii)	Outline the difference in mRNA production for the three genes during the submergence period for variety O. sativa indica.
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(2)

(d)	Using only this data, deduce which gene confers submersion resistance to rice plants.
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(2)
 
	The OsGI gene causes long-day flowering and the effect of its overexpression has been observed in a transgenic variety of rice. Some wild-type rice (WT) and transgenic plants were exposed to long days (14 hours of light per day) and others to short days (9 hours of light per day).
	The shades of grey represent the genotypes of the transgenic plants, where:

	[Adapted by permission from Macmillan Ltd, Ueguchi-Tanaka, M et al. 2005.  “Gibberellin-insensitive dwarf1 encodes a soluble receptor for gibberellins”. Nature. Vol 437. Pp 693–698. Copyright (2005).]

(e)	(i)	State the overall effect of overexpression of the OsGI gene in plants treated with short-day light.
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(1)
 
(ii)	Compare the results between the plants treated with short-day light and the plants treated with long-day light.
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(2)
 
(iii)	State, giving one reason taken from the data opposite, if unmodified rice is a short-day plant or a long-day plant.
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(1)
 
(f)	Discuss, using only the data opposite, if OsGI+ and OsGI– behave as codominant alleles.
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(2)

(g)	Evaluate, using all the data, how modified varieties of rice could be used to overcome food shortages in some countries.
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(2)
(Total 19 marks)

16.	(a)	The photograph below shows the flowers of Campanula persicifolia. Label structures I, II and III.

[Source: photograph provided by IB examiner]
(3)

(b)	(i)	Using the external features shown in the photograph, state the phylum to which this plant belongs.
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(1)
 
(ii)	Comment on the hypothesis that the plant shown in the photograph could be pollinated by an animal.
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(2)
 
(c)	Outline the use of the binomial system of nomenclature in Campanula persicifolia.
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(2)
(Total 8 marks)

17.	What is a difference between the features of monocotyledons and dicotyledons?

	Monocotyledons	Dicotyledons	
A.	Tap roots	Fibrous roots	
B.	Two seed-leaves	One seed-leaf	
C.	Vascular tissue in rings in the stem	Vascular tissue scattered through the stem	
D.	Parallel-veined leaves	Net-veined leaves	
(Total 1 mark)

18.	What causes stomata to close?
A.	Increase in the turgor of the guard cells
B.	A high level of CO2 in the leaf tissues
C.	The presence of abscisic acid
D.	Movement of K+ into the guard cells
(Total 1 mark)

19.	What is the correct sequence of events in the germination of a starch seed?

A.	gibberellin
produced		water
absorbed		hydrolysis of
food reserves		protein
synthesis		enzymes
produced	
B.	water
absorbed		hydrolysis of
food reserves		protein
synthesis		gibberellin
produced		enzymes
produced	
C.	water
absorbed		gibberellin
produced		protein
synthesis		enzymes
produced		hydrolysis of
food reserves	
D.	gibberellin
produced		water
absorbed		protein
synthesis		enzymes
produced		hydrolysis of
food reserves	
(Total 1 mark)

20.	Which plant hormone is responsible for the closing of the stomata?
A.	Gibberellic acid
B.	Abscisic acid
C.	Phytochromes
D.	Ethylene
(Total 1 mark)

21.	Which of the following are features of the dicotyledonous plants?
I.	Parallel leaf veins
II.	Flower parts in groups of three
III.	Two seed-leaves (cotyledons)
A.	III only
B.	II and III only
C.	I and II only
D.	I, II and III
(Total 1 mark)

22.	(a)	Draw a labelled diagram of the structure of a chloroplast as seen with an electron microscope.
(4)
 
(b)	Describe how water is carried by the transpiration stream.
(7)
 
(c)	Explain how flowering is controlled in long-day and short-day plants.
(7)
(Total 18 marks)

23.	Up to two additional marks are available for the construction of your answers.
(2)
	(a)	Draw a labelled diagram showing the tissues present in a dicotyledonous leaf.
(4)
(b)	Outline the light-dependent reactions of photosynthesis.
(6)
(c)	Explain the effect of light intensity and temperature on the rate of photosynthesis.
(8)
(Total 20 marks)

24.	What are the main structures in a bulb and their function?
A.	Flowers for sexual reproduction
B.	Enlarged roots for nutrient absorption from the soil
C.	Swollen leaf bases for food storage
D.	Thickened stems for water storage
(Total 1 mark)

25.	What generates new cells in dicotyledonous plants?
I.	Apical meristems
II.	Lateral meristems
III.	Phloem
A.	I only
B.	II only
C.	I and II only
D.	I, II and III
(Total 1 mark)

26.	What is the effect of abscisic acid on transpiration?
A.	It increases transpiration by causing the stomata to open.
B.	It decreases transpiration by causing the stomata to close.
C.	It increases transpiration by decreasing the humidity inside the leaf.
D.	It decreases transpiration by increasing the humidity inside the leaf.
(Total 1 mark)

27.	Up to two additional marks are available for the construction of your answers.
(2)
	(a)	Outline the thermal, cohesive and solvent properties of water.
(5)
 
(b)	Outline adaptations of xerophytes.
(4)
 
(c)	Explain the role of the kidney in maintaining water balance in humans.
(9)
(Total 20 marks)

28.	(a)	State two types of meristem found in plants.
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(1)
 
(b)	Outline two differences in structure between monocotyledonous and dicotyledonous plants.
Structure	Monocotyledonous	Dicotyledonous	

			

			
(2)
 
(c)	State two methods by which terrestrial plants support themselves.
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(1)

(d)	Explain how auxin controls the response of a plant to light.
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(3)
(Total 7 marks)