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- A student divided a small air tight box into two chambers with wire mesh. In one chamber he kept a number of rats and in...(Solved)
A student divided a small air tight box into two chambers with wire mesh. In one chamber he kept a number of rats and in the other a number of potted plants. What was likely to happen if the box was placed in the dark for two hours? Explain your answer.
Date posted: September 13, 2019.
- Describe what happens in the first phase of aerobic respiration.(Solved)
Describe what happens in the first phase of aerobic respiration.
Date posted: September 13, 2019.
- State one example of chromosomal mutation that lead to
(i) Change in chromosomal structure
(ii) Change in chromosomal number(Solved)
State one example of chromosomal mutation that lead to
(i) Change in chromosomal structure
(ii) Change in chromosomal number
Date posted: September 13, 2019.
- The following are short messages (sms) on cell phone communication between Mrs. Mkenzie and her husband. They can be used as analogies of gene mutation.(Solved)
The following are short messages (sms) on cell phone communication between Mrs. Mkenzie and her husband. They can be used as analogies of gene mutation.
For each of these messages identify the type of gene mutation illustrated
Date posted: September 13, 2019.
- When transplanting a seedling, it is advisable to remove some of the leaves. Explain(Solved)
When transplanting a seedling, it is advisable to remove some of the leaves .Explain
Date posted: September 13, 2019.
- The figure below shows the embryo-sac before fertilization.(Solved)
The figure below shows the embryo-sac before fertilization.
(a) Identify the structures labeled A and B.
(b) Identify the structures labelled in the diagram that will develop into the following after fertilization.
(i) Embryo
(ii) Endosperm
(c) State the ploidy of each the following nucleic after fertilization
(i) C
(ii) D
Date posted: September 13, 2019.
- In maize the gene for the purple colour is dorminant for the gene for white colour. A purple colour was crossed with heterozygous plant. Using...(Solved)
In maize the gene for the purple colour is dorminant for the gene for white colour. A purple colour was crossed with heterozygous plant. Using letter G to represent the gene for purple colour, work out the genotypic ratio of the offspring. Show your working.
Date posted: September 13, 2019.
- State two factors that denature enzymes.(Solved)
State two factors that denature enzymes.
Date posted: September 13, 2019.
- Why does a membrane form around the egg after fertilization?(Solved)
Why does a membrane form around the egg after fertilization?
Date posted: September 13, 2019.
- A student was using a microscope whose eyepiece lens was marked X4. The high powered objective lenses were marked X10. Calculate the total magnification of...(Solved)
A student was using a microscope whose eyepiece lens was marked X4. The high powered objective lenses were marked X10. Calculate the total magnification of the microscope
Date posted: September 13, 2019.
- Distinguish between Attenuation and Vaccination?(Solved)
Distinguish between Attenuation and Vaccination?
Date posted: September 13, 2019.
- The diagrams below illustrate some chromosome mutations.(Solved)
The diagrams below illustrate some chromosome mutations.
(a) Identify the mutations illustrated above.
(b) Give an example of a disorder in humans caused by mutation A above.
Date posted: September 13, 2019.
- Give an example of a beneficial mutation in plants.(Solved)
Give an example of a beneficial mutation in plants.
Date posted: September 13, 2019.
- (a) In which organ is cardiac muscle found.
(b) What is the function of the cardiac muscle in the organ you have named in (a)...(Solved)
(a) In which organ is cardiac muscle found.
(b) What is the function of the cardiac muscle in the organ you have named in (a) above.
Date posted: September 13, 2019.
- (a) Given a sample of urine, name one test you would carry out to determine if it was obtained from a person suffering from diabetes...(Solved)
(a) Given a sample of urine, name one test you would carry out to determine if it was obtained from a person suffering from diabetes mellitus.
(b) What results are expected if one is diabetic?
Date posted: September 13, 2019.
- A goat weighing 20kg requires 216KJ while a mouse weighing 54gms requires 2830KJ per day. Explain.(Solved)
A goat weighing 20kg requires 216KJ while a mouse weighing 54gms requires 2830KJ per day. Explain.
Date posted: September 13, 2019.
- In a prolonged drought period, forage was scarce. It made animals reach out for higher forage and this way the giraffes got the stretched long...(Solved)
In a prolonged drought period, forage was scarce. It made animals reach out for higher forage and this way the giraffes got the stretched long necks.
(a) What is the term used for a characteristic such as the long necks outlined?
(b) What is the name given to the theory that describes the evolution of such structures like the long necks?
(c) State and explain the limitation of the theory you named in (b) above.
Date posted: September 13, 2019.
- The table below shows differences in air breathed in and out.(Solved)
The table below shows differences in air breathed in and out.
What is the reason for there differences.
Date posted: September 13, 2019.
- Which substance in the cigarettes smoke may cause lung cancer.(Solved)
Which substance in the cigarettes smoke may cause lung cancer.
Date posted: September 13, 2019.
- Mr. Juma has sued Serenity Hospital on grounds that their child was wrongly identified such that they got the wrong one.The child is blood group...(Solved)
Mr. Juma has sued Serenity Hospital on grounds that their child was wrongly identified such that they got the wrong one.The child is blood group O. Mr. Juma is blood group AB while Mrs. Juma is heterozygous blood group A.
(a) Work out the possible blood group of their offsprings.
(b) Is Mr. Juma justified in his claims?
Date posted: September 13, 2019.
- The diagram below show single circulation of a fish.(Solved)
The diagram below show single circulation of a fish.
(a) Write down the names of the parts labelled T,U and V.
(b) Explain the main disadvantage of this type of circulation.
(c) How is this type of circulation different from that found in man?
Date posted: September 13, 2019.
- The table below shows approximate numbers of organisms found in an ecosystem.(Solved)
The table below shows approximate numbers of organisms found in an ecosystem.
(a) Using the information in the table draw a pyramid of numbers.
(b) Explain what would happen to the other organisms if all the lizards suddenly died off.
Date posted: September 13, 2019.
- The photographs labelled K, L, M, N and P below are bones obtained from a mammal. For each of the bones K, L and M,...(Solved)
The photographs labelled K, L, M, N and P below are bones obtained from a mammal. For each of the bones K, L and M, two views are shown.
(a) Identify the bones and name the part of the mammalian body from which each was obtained. (5mks)
(b) Name the parts labelled 1, 2 and 4.
(c) Name the bones that form a joint with bone K at its anterior and posterior end
and in each case name the type of joint they form.
Anterior end.
(i) Bone(s)
(ii) Type of joint
Posterior end.
(i) Bone(s)
(ii) Type of joint
(d) State the function of the structure labelled 6 in bone P.
Date posted: September 13, 2019.
- Name the hard body covering found in organisms of the phylum arthropoda.(Solved)
Name the hard body covering found in organisms of the phylum arthropoda.
Date posted: September 13, 2019.
- Write the kingdoms to which the following organisms belong.
Plasmodium
Bat
Yeast(Solved)
Write the kingdoms to which the following organisms belong.
Plasmodium
Bat
Yeast
Date posted: September 13, 2019.
- A student collected a plant with the following features:
-Vascular bundles in the stem were scattered with no cambium.
-Fibrous root system.
Name the sub-division and the class...(Solved)
A student collected a plant with the following features:
-Vascular bundles in the stem were scattered with no cambium.
-Fibrous root system.
Name the sub-division and the class to which the above plant belonged.
Sub-division
Class
Date posted: September 13, 2019.
- Name one waste product that is transported in the blood but not removed by the kidneys.(Solved)
Name one waste product that is transported in the blood but not removed by the kidneys.
Date posted: September 13, 2019.
- Arrange the following nitrogenous waste products in order of decreasing toxicity:
urea, uric acid and ammonia.(Solved)
Arrange the following nitrogenous waste products in order of decreasing toxicity:
urea, uric acid and ammonia.
Date posted: September 13, 2019.
- Name two substances that are excreted through diffusion process in plants.(Solved)
Name two substances that are excreted through diffusion process in plants.
Date posted: September 13, 2019.
- Explain why the garden pea plant was preferred by Gregor Mendel in his crossing experiments.(Solved)
Explain why the garden pea plant was preferred by Gregor Mendel in his crossing experiments.
Date posted: September 13, 2019.