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Reduce oxygen supply and hence suffocation and death of plants and animals, clog respiratory surfaces (gills and stomata) leading to death;
Kavungya answered the question on June 15, 2019 at 06:34
- State the advantage of a biological control method over the chemical control method of pests and parasites(Solved)
State the advantage of a biological control method over the chemical control method of pests and parasites
Date posted: June 15, 2019. Answers (1)
- Explain why Biomass of producers is greater than that of primary consumers in a balanced ecosystem.(Solved)
Explain why Biomass of producers is greater than that of primary consumers in a balanced ecosystem.
Date posted: June 15, 2019. Answers (1)
- Explain why the biomass of organisms decreases at each preceding trophic level.(Solved)
Explain why the biomass of organisms decreases at each preceding trophic level.
Date posted: June 15, 2019. Answers (1)
- Birds feed on grasshoppers that feed on grass.
Draw a possible food chain from the above information(Solved)
Birds feed on grasshoppers that feed on grass.
Draw a possible food chain from the above information
Date posted: June 15, 2019. Answers (1)
- A student wanted to estimate the number of grasshoppers in 5km2 grass field near the school compound.
Using a sweep net he captured 36 grasshoppers. He...(Solved)
A student wanted to estimate the number of grasshoppers in 5km2 grass field near the school compound.
Using a sweep net he captured 36 grasshoppers. He used a red felt pen to mark the thorax of each insect before releasing back into the field. Three days later he made another catch of grasshoppers. He collected 45 grasshoppers of which only 4 had been marked with red mark.
a) Name the above method used in the population estimation
b) Calculate the population of grasshoppers using the above data
Date posted: June 15, 2019. Answers (1)
- Explain one demerit of transpiration in plants(Solved)
Explain one demerit of transpiration in plants
Date posted: June 14, 2019. Answers (1)
- Describe and explain the relationship between the stomatal aperture and transpiration rate.(Solved)
Describe and explain the relationship between the stomatal aperture and transpiration rate.
Date posted: June 14, 2019. Answers (1)
- The graph below shows the changes in transpiration rate and the width of the stomatal aperture in Zea mays (maize) over a 24-hour period.
a) What...(Solved)
The graph below shows the changes in transpiration rate and the width of the stomatal aperture in Zea mays (maize) over a 24-hour period.
a) What is meant by the term transpiration?
b) Account for the rate of transpiration between
i)3am and 5am
ii)6am -12 noon
iii)1.00 pm -9.00 pm
Date posted: June 14, 2019. Answers (1)
- State the reasons why glucose level should be maintained constant.(Solved)
State the reasons why glucose level should be maintained constant.
Date posted: June 14, 2019. Answers (1)
- Name one example of a characteristic in man that is transmitted by multiple alleles.(Solved)
Name one example of a characteristic in man that is transmitted by multiple alleles.
Date posted: June 14, 2019. Answers (1)
- State the importance of crossing over in the study of genetics(Solved)
State the importance of crossing over in the study of genetics
Date posted: June 14, 2019. Answers (1)
- Give 2 advantages of cross-pollination over self-pollination.(Solved)
Give 2 advantages of cross-pollination over self-pollination.
Date posted: June 14, 2019. Answers (1)
- Suggest the biological significance of each of the following
i) Development of the pollen tube in fertilization in plants.
ii) Fusion of petals to form funnel-shaped corolla...(Solved)
Suggest the biological significance of each of the following
i) Development of the pollen tube in fertilization in plants.
ii) Fusion of petals to form funnel-shaped corolla tube in certain
flowers.
Date posted: June 14, 2019. Answers (1)
- The diagram below shows exchange of materials between embryo’s bloodstreams and mother’s blood stream(i) Give the names of the parts labelled E and GEG(ii) Name...(Solved)
The diagram below shows exchange of materials between embryo’s bloodstreams and mother’s blood stream
(i) Give the names of the parts labelled E and G
E
G
(ii) Name one substance that is in high concentration in E
(iii) In which organ does this kind of exchange shown occur?
Date posted: June 14, 2019. Answers (1)
- Give the functions of muscles in the alimentary canal(Solved)
Give the functions of muscles in the alimentary canal.
Date posted: June 4, 2019. Answers (1)
- When storing a pair of bar magnets, it is advisable to put a keeper at each end.
a) Draw a diagram in the space below to...(Solved)
When storing a pair of bar magnets, it is advisable to put a keeper at each end.
a) Draw a diagram in the space below to show the above arrangement and label the poles of each magnet.
b) Explain briefly how the above arrangement can minimize the loss of magnetism in the bar magnets.
Date posted: May 29, 2019. Answers (1)
- How is the dry mass of a leaf determined?(Solved)
How is the dry mass of a leaf determined?
Date posted: May 29, 2019. Answers (1)
- Explain why a green leaf is normally tested for the presence of starch instead of glucose.(Solved)
Explain why a green leaf is normally tested for the presence of starch instead of glucose.
Date posted: May 29, 2019. Answers (1)
- In a physiological experiment, starch, protein, diastase and sodium chloride (common salt) were added
to water and put inside a visking tubing. The visking tubing was...(Solved)
In a physiological experiment, starch, protein, diastase and sodium chloride (common salt) were added
to water and put inside a visking tubing. The visking tubing was then placed in a water bath maintained at a temperature between 350C and 400C. The set-up was as shown in the diagram below.
The following observations were made after the procedures indicated.
(a) Name the process by which salt moved into the water in the beaker from the visking tubing.
(b) (i) Name the food substance responsible for the brown colour observed after one hour both in the beaker and visking tubing when solutions were boiled with Benedict’s solution.
(ii) Account for the observation in b(i) above.
(c) (i) Name the food substance tested with sodium hydroxide followed by copper sulphate solutions.
(ii) Account for the absence of the food substance named in c(i) above in the beaker after1 hour.
(d) After one hour, the visking tubing was firm. State the term used to describe this state.
Date posted: May 29, 2019. Answers (1)
- The diagram below represents a section through the mammalian ear. Study it and answer the questions that follow.
(a) Name the structures labelled H and J....(Solved)
The diagram below represents a section through the mammalian ear. Study it and answer the questions that follow.
(a) Name the structures labelled H and J.
(b) State how the structures labelled H, M and N are adapted to their functions. H,M,N.
(c) State what would happen if the structure labelled K was completely damaged?.
(d) Name the fluid contained in structure N.
(e) Apart from hearing, state the other role performed by the human ear.
Date posted: May 29, 2019. Answers (1)