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The concentration of carbon IV oxide in a tropical forest was measured during the course of 24 hour period from mid-night. The graph below shows the results obtained.
Account for the results obtained at:
(i) Midnight.
(ii) At 12.00 noon
Date posted:
October 4, 2019
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a)Name the specific part of the chloroplast where the following processes occur.
(i) Carbon IV oxide fixation
(ii) Photolysis
(b) State one way in which the dark reactions of photosynthesis depends on light reaction.
Date posted:
October 4, 2019
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The table below shows three enzymes A, B and C and their respective optimum pH.
(i) Name the most likely region of the alimentary canal of a mammal where enzyme B would be found.
(ii) Give a reason for your answer in (a) (i) above
Date posted:
October 4, 2019
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The diagram below represents a cell organelle.
(i) Name the part labeled y
(ii) State the function of the part labeled X
State the function of the vitamin named in (i) above
Date posted:
October 4, 2019
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Below is a process that takes place along the mammalian digestive system.
(a) Name the processes represented by A and B
(b) Name part of the alimentary canal where the process B takes place
Date posted:
October 4, 2019
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Briefly explain the fate of the following products from the light stage of the process of
Photosynthesis:
(a) Oxygen
(b) Hydrogen
(c) ATP
Date posted:
October 3, 2019
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State two ways in which guard cells differ from other epidermal cells.
Date posted:
October 3, 2019
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Briefly explain the symbiotic relationship in the root nodule of a leguminous plant.
Date posted:
October 3, 2019
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Briefly explain the effect of poisoning the roots hair on the uptake of nitrate by plants.
Date posted:
October 3, 2019
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b)State the role of emulsification in the digestion of fats in the alimentary canal.
b) What is the function of hydrochloric acid in the alimentary canal.
Date posted:
October 3, 2019
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The diagram below represents a cell organelle.
i) Name the part labeled Y
ii) State the function of the part labeled X
Date posted:
October 3, 2019
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The diagram below is of a certain type of neurons
(a) Identify the type of neuron
(b) Give a reason for your answer in (a) above
(c) Give the functions of the parts labeled A, B, and D
Date posted:
October 3, 2019
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A solution of sugar cane was boiled with hydrochloric acid and sodium hydrogen carbonate was added to the solution, which was then boiled with benedicts solution. An orange precipitate was formed.
(a) Why was the solution boiled with hydrochloric acid and then sodium hydrogen carbonate added in it
(b) To which class of carbohydrates does sugar cane belong?
(c) State the form in which carbohydrates are:
(i) Transported in animals
(ii) Transported in plants
Date posted:
October 3, 2019
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The following reaction may occur in a forward and backward direction.
(a) Name the organelle where the reaction occurs in:
(i) Forward direction
(ii) Backward direction
(b) Give one difference and one similarity for the two organelles named in (a) above
Date posted:
October 3, 2019
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One of the components of bile is a chemical left over from destruction of red blood cells.
i) Identify the chemical substance
ii) What is the role of bile in digestion
Date posted:
October 3, 2019
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State two ways in which the guard cells differ their adjacent epidermal cells
Date posted:
October 3, 2019
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The diagram below shows how food boles move along the human esophagus and the Intestine.
(a) Identify the process illustrated in the diagram
(b) Briefly state how the movement of food boles from position 1 to position 2 is achieved
(c) Name one component of a persons diet that assists in the movement of food described in
(b) above
Date posted:
October 3, 2019
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Name the diseases caused by deficiency of :
(a) Iodine
(b) Vitamin C
Date posted:
October 3, 2019
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A biological washing detergent contains enzymes which remove stains like mucus and oils from clothes which are soaked in water with the detergent:-
(a) Name two groups of enzymes that are present in detergent
(b) Explain why stains would be removed faster with the detergent in water at 35 degree C rather than at 15 degrees C
Date posted:
October 3, 2019
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State three adaptations of aquatic plants to photosynthesis.
Date posted:
October 3, 2019
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The diagram below shows chemical reactions A and B which are controlled by enzymes x and y.
(a) Name:
(i) Reaction A.
(ii) Enzyme y
Date posted:
October 3, 2019
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a) A leaf of a potted plant kept in darkness for 48hours was smeared with Vaseline jelly then exposed to sunlight for 8hours. Explain why the test for starch in the leaf was negative.
(b) Name two other processes that were interfered with in the plant.
Date posted:
October 3, 2019
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The diagram below shows cells in plants:-
(a) Identify the cells shown above
(b) Explain how the cells are adapted to their function
(c) Explain how accumulation of carbon (IV) Oxide in the cells above would lead to the closure of structure A
Date posted:
October 3, 2019
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The two cells shown below are obtained from two different potato cylinders which were immersed in tow different solutions P and Q.
a)
i) Name the structure labelled A.
ii) State the function of structure B.
b) If eight of cell I were observed across the diameter of the filed of view of 0.5 mm. Work out the actual diameters of each cell in micrometers.
c) Suggest the identity of the solution Q.
d) Account for the change in cell I above.
e) State any one importance of the physiological process being demonstrated above in animals
Date posted:
October 3, 2019
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Two fresh potato cylinders of equal length were placed one in distilled water and the other in concentrated sucrose solution:
(a) Account for the change in length of the cylinder in:
(i) Distilled water
(ii) Sucrose solution
(b)
(i) What would be the result in terms of length if a boiled potato was used?
(ii) Explain your answer in(b)(i) Above
(c) State two uses of the physiological process being demonstrated in the experiment
Date posted:
October 3, 2019
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Name two plant processes in which diffusion plays an important role.
Date posted:
October 3, 2019
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Name support tissues in plants characterized by the following
(i) Cells being turgid
(ii) Cells being thickened by cellulose
(iii) Cells being thickened by lignin
Date posted:
October 3, 2019
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An experiment was carried out to investigate the effect of different concentrations of sodium chloride on human red blood cells. Equal amounts of blood were added to equal volumes of the salt solution but of different concentrations. The results are shown in the table below.
(a) Account for the results in the set-up
(b) If the experiment was repeated using 1.4% sodium chloride solution, state the expected results with reference to:
(i) the number of red blood cells
(ii) the appearance of red blood cells if viewed under the microscope
Date posted:
October 3, 2019
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Briefly state two adaptation for each of the following cells to their functions
(i) Spermatozoon
(ii) Palisade mesophlly cell
Date posted:
October 3, 2019
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The figure below shows the results obtained when red blood cells are put in different solutions.
(a) What is the name given to the process that occurs when the cell is put into solution B?
(b) Compare the results obtained when the cell is put in solution B to the results that would be obtained if a plant cell was put in the same solution
Date posted:
October 3, 2019