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-Enzyme stratus of seeds;
-Maturity of embryo;
-Health status of seeds ;
-Presence of germination inhibitors ;
sharon kalunda answered the question on May 29, 2019 at 09:36
- An experiment was set up to study the response of woodlice to light. Ten woodlice were placed in a glass tube. After five minutes
one end...(Solved)
An experiment was set up to study the response of woodlice to light. Ten woodlice were placed in a glass tube. After five minutesone end of the tube was covered with black paper to make it dark. The number of woodlice in light and dark was then recorded every minute for five minutes.The diagram below shows the apparatus used.
The table below shows the results of the experiment.
i) Why were the woodlice left there for five minutes before the pack paper was placed on the tube?
ii) Complete the line graph on the grid below to show the number of woodlice found in the dark at each minute during the
experiment. The results for woodlice in light have already been plotted.
iii) State a conclusion which can be drawn from the results of this experiment.
c) A student repeated this experiment.
i) How could the design be changed to make the results more reliable?
ii) State one environmental factor which would be kept the same to allow a valid comparison with the first experiment.
Date posted: May 29, 2019. Answers (1)
- In an investigation, young plant shoots were exposed to 48hrs of light from above or from one side only. Their growth responses are shown in...(Solved)
In an investigation, young plant shoots were exposed to 48hrs of light from above or from one side only. Their growth responses are shown in the diagrams below.
i) Name the response shown by the shoots and explain the advantages of this response to the plants.
ii) Account for the growth response of shoot B after 48 hours.
Date posted: May 29, 2019. Answers (1)
- A group of students set up the following experiments to investigate the factors that affect enzymes
a) Identify the property of enzymes being investigated in tubes...(Solved)
A group of students set up the following experiments to investigate the factors that affect enzymes
a) Identify the property of enzymes being investigated in tubes 1 and 2.
b) After 3 hours the students tested the content in the four tubes for starch. They obtained the following results in tube 2, 3 and 4.
Tube 2 - Blue-black colour
Tube 3 - Brown colour of iodine remained
Tube 4 - Blue black colour.
Account for the results obtained in tube 3 and 4.
c) What results would you expect in tube 3 if temperature was maintained at 5°C? Give a reason for your answer.
Date posted: May 29, 2019. Answers (1)
- What problems are experienced by fresh water and marine fish in their habitats.(Solved)
What problems are experienced by fresh water and marine fish in their habitats.
Date posted: May 29, 2019. Answers (1)
- Work out a cross between a haemophilic man married to a carrier woman for haemophilia.(Solved)
Work out a cross between a haemophilic man married to a carrier woman for haemophilia.
Date posted: May 29, 2019. Answers (1)
- Explain why certain bacteria and other pathogens become resistant to drugs after sometime.(Solved)
Explain why certain bacteria and other pathogens become resistant to drugs after sometime.
Date posted: May 29, 2019. Answers (1)
- Complete the table below which shows some parasites and the disease they cause.(Solved)
Complete the table below which shows some parasites and the disease they cause.
Date posted: May 29, 2019. Answers (1)
- Name the disease caused by the schistosoma.(Solved)
Name the disease caused by the schistosoma.
Date posted: May 29, 2019. Answers (1)
- State four adaptive features that make schistosoma a successful endoparasite.(Solved)
State four adaptive features that make schistosoma a successful endoparasite.
Date posted: May 29, 2019. Answers (1)
- State two functions of muscles found in the reproductive system in females.(Solved)
State two functions of muscles found in the reproductive system in females.
Date posted: May 29, 2019. Answers (1)
- Below is a simplified diagram of a flower.
i) Suggest its agent of pollination.
ii) Name the type of ovary shown above.
iii) Explain one observable...(Solved)
Below is a simplified diagram of a flower.
i) Suggest its agent of pollination.
ii) Name the type of ovary shown above.
iii) Explain one observable mechanism that will hinder self pollination and fertilization in the above flower.
Date posted: May 29, 2019. Answers (1)
- The diagram below represents part of a mammalian respiratory system.
a) Name the structure.
b) State two observable ways in which the structure is suited to...(Solved)
The diagram below represents part of a mammalian respiratory system.
a) Name the structure.
b) State two observable ways in which the structure is suited to its function.
Date posted: May 29, 2019. Answers (1)
- Explain why the rate of transpiration is reduced when humidity is high.(Solved)
Explain why the rate of transpiration is reduced when humidity is high.
Date posted: May 29, 2019. Answers (1)
- Name the three processes that takes place in the liver to bring about difference in composition of blood in hepatic portal vein and hepatic vein.(Solved)
Name the three processes that takes place in the liver to bring about difference in composition of blood in hepatic portal vein and hepatic vein.
Date posted: May 29, 2019. Answers (1)
- A horse has 64 chromosomes in its somatic cells while a donkey had 62. A mule is produced when a horse mates with a donkey.
However...(Solved)
A horse has 64 chromosomes in its somatic cells while a donkey had 62. A mule is produced when a horse mates with a donkey.
However a mule is sterile.Work out the number of chromosomes in a mule. Show your working.
Date posted: May 29, 2019. Answers (1)
- Why is the mule sterile?(Solved)
Why is the mule sterile?
Date posted: May 29, 2019. Answers (1)
- How is the dark stage of photosynthesis dependent to light stage.(Solved)
How is the dark stage of photosynthesis dependent to light stage.
Date posted: May 29, 2019. Answers (1)
- Two glucose molecules combine to form the disaccharide sucrose. The moleculer formula of glucose is C6H12O6 while a single sucrose molecule has the molecular formula...(Solved)
Two glucose molecules combine to form the disaccharide sucrose. The moleculer formula of glucose is C6H12O6 while a single sucrose molecule has the molecular formula C12H22O11. Account for the observation.
Date posted: May 29, 2019. Answers (1)
- If a solution of 0.9% salt solution is isotonic to a certain type of animal cell, explain what happens when the animal cell is placed...(Solved)
If a solution of 0.9% salt solution is isotonic to a certain type of animal cell, explain what happens when the animal cell is placed in a solution of 1.2% salt solution.
Date posted: May 29, 2019. Answers (1)
- The red blood cells lack mitochondria.
a) How is this advantages to red blood cells?
b) Apart from the reason stated above, give one other reason.(Solved)
The red blood cells lack mitochondria.
a) How is this advantages to red blood cells?
b) Apart from the reason stated above, give one other reason.
Date posted: May 29, 2019. Answers (1)