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(a) Effect of temperature on enzymes ;
(b) So that contents of the tubes will have attained the temperature of the waterbath.
(c) A - Would turn blue black
B - Would turn brown / colour of iodine remained
C - Would turn blue black
(d) A - Very low temperature which inactivated enzyme / ptyalin / salivary amylase thus no digestion of starch.
B - Suitable temperature / favourable temperature / optimum / best temperature for activity of enzyme /salivary /amylase / ptyalin thus starch digested.
C - Temperature high / above optimum thus denaturing enzyme thus no digestion of starch.
sharon kalunda answered the question on March 21, 2019 at 14:12
- Sickle cell anaemia is a hereditary disease due to a recessive gene which changes normal haemoglobin (Hb – A) to abnormal
haemoglobin (Hb – S). The...(Solved)
Sickle cell anaemia is a hereditary disease due to a recessive gene which changes normal haemoglobin (Hb – A) to abnormal
haemoglobin (Hb – S). The red blood cells of people with sickle cell anaemia are sickle shaped.
(a) What are the possible phenotypes of the offsprings of a man who is heterozygous and a woman who is also heterozygous?
Show your working.
(b) Sickle cell trait is more prevalent in tropical countries than in temperate countries. Give an explanation for this observation.
Date posted: March 21, 2019. Answers (1)
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Below is a diagram of a sperm cell.
a) Identify parts labeled X and Y.
(b) Explain how parts W and Z adapt the cell to its function.
(c) Using letter P identify or label on the diagram the part of the cell rich in DNA.
(d) State the function of part X.
Date posted: March 21, 2019. Answers (1)
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The figure shown below represents a kidney nephron. Use it to answer the questions that follow.
(a) (i) X is made up of a tuft of capillaries. How do they differ from other capillaries in the body?
(ii) What structural difference exist between W and Z?
(iii) State the significance of the difference stated in (a) (ii) above.
(b) State three adaptations that enable P to perform its function.
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Date posted: March 21, 2019. Answers (1)
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The shoots were treated as follows.
(a)...(Solved)
An experiment was carried out to investigate the effect of hormones on growth of lateral buds of three pea plants.
The shoots were treated as follows.
(a) Shoot A – Apical bud was removed.
(b) Shoot B – Apical bud was removed and gibberellic acid placed on the cut shoot.
(c) Shoot C – Apical bud was left intact.
The lengths of the branches developing from the lateral buds were determined at regular intervals. The results obtained are shown in the table below.
(i) Using the same axes, draw graphs to show the lengths of branches against time.
(ii) (a) What was the length of the branch in Shoot B on the 7th day?
(b) What would be the expected length of the branch developing from Shoot B on the 11th day?
(iii) Account for the results obtained in the experiment.
(iv) Why was Shoot C included in the experiment?
(v) What is the importance of gibberellic acid in agriculture?
vi)State two physiological processes that are brought about by the application of gibberellic acid on plants.
Date posted: March 21, 2019. Answers (1)
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Date posted: March 21, 2019. Answers (1)
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Date posted: March 21, 2019. Answers (1)
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(a) Typhoid
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Date posted: March 21, 2019. Answers (1)
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ii) What was the role of sodium hydrogen carbonate in the experiment?
Date posted: March 21, 2019. Answers (1)
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(b) List the two types of sensory cells found in...(Solved)
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Date posted: March 21, 2019. Answers (1)
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Date posted: March 15, 2019. Answers (1)