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i) To carry out test for starch on a leaf
ii) A - To kill the protoplasm of the leaf or to breakdown starch grains or to stop enzyme activity
B- To discolour the leaf or remove chlorophyll
C - To soften the leaf, remove any traces of ethanol
iii) Iodine solution
iv) Iodine solution changes colour from yellow/ brown to black/ blue balck
johnmulu answered the question on May 1, 2017 at 10:04
- A potted plant was kept in the dark for 48 hours. Two leaves X and Y were treated as shown in the diagram below. (Solved)
A potted plant was kept in the dark for 48 hours. Two leaves X and Y were treated as shown in the diagram below.
The experimental set-up was kept in sun light for six hours after which a starch test was carried out on the two leaves
a) What were the results of the starch test on leaves X and Y?
b) Give reasons for your answers in (a) above
Date posted: May 1, 2017. Answers (1)
- The diagram below represents a set - up that was used to investigate certain process in a plant. (Solved)
The diagram below represents a set - up that was used to investigate certain process in a plant.
a) State the process that was being investigated
b) State a factor that would affect the process
Date posted: May 1, 2017. Answers (1)
- a) State the function of cristae in mitochondria.
b) The diagram below represents a cell organelle(Solved)
a) State the function of cristae in mitochondria.
b) The diagram below represents a cell organelle
i) Name the part labeled Y.
ii) State the function of the part labeled X
Date posted: May 1, 2017. Answers (1)
- The diagram below represents a cell.(Solved)
The diagram below represents a cell.
a) Name the parts labeled X and Y
b) Suggest why structures labelled X and would be more on one side than the other
Date posted: May 1, 2017. Answers (1)
- The graph below shows the effect of substrate concentration on the rate of enzyme reaction(Solved)
The graph below shows the effect of substrate concentration on the rate of enzyme reaction
a) i) Account for the shape of the graph between A and B.
ii) B and C
b) How can the rate of reaction be increased after point B?
c) State two other factors that affect the rate of enzyme reaction
Date posted: May 1, 2017. Answers (1)
- In an experiment to investigate a factor affecting photosynthesis, a leaf of a potted plant which had been kept in the dark overnight was covered with aluminum foil as shown in the diagram below.(Solved)
In an experiment to investigate a factor affecting photosynthesis, a leaf of a potted plant which had been kept in the dark overnight was covered with aluminum foil as shown in the diagram below.
The set up was kept in sunlight for three hours after which a food test was carried out on the leaf.
a) Which factor was being investigated in the experiment?
b) What food test was carried out?
c) Why was it necessary to keep the plant in darkness before the experiment?
Date posted: May 1, 2017. Answers (1)
- A freshly obtained dandelion stem measuring 5 cm long was split lengthwise to obtain two similar pieces.(Solved)
A freshly obtained dandelion stem measuring 5 cm long was split lengthwise to obtain two similar pieces. The pieces were placed in solutions of different concentrations in petri dishes (L1 and L2) for 20 minutes. The appearance after 20 minutes is as shown
State the significance of the biological process involved in the experiment
Date posted: May 1, 2017. Answers (1)
- Students set up an experiment as illustrated below.(Solved)
Students set up an experiment as illustrated below.
a)Name the physiological process that resulted in the observations made after 30 minutes.
b) State the importance of the physiological process investigated in plants.
c) Explain the observation made after 30 minutes
Date posted: May 1, 2017. Answers (1)
- The table below shows the concentration of sodium and iodine in sea water and cell sap of a plant(Solved)
The table below shows the concentration of sodium and iodine in sea water and cell sap of a plant
a) i) Name the process through which the plant cells take up sodium ions.
ii) Give a reason for your answer in (a) above
b) If the plant was sprayed with a chemical that inhibits respiration:
i) Which of the two ions uptake will be affected?
ii) Give a reason for your answer in (b) (i) above
Date posted: May 1, 2017. Answers (1)
- State two ways in which chloroplasts are adapted to their function.(Solved)
State two adaptations of chloroplast to its function
Date posted: May 1, 2017. Answers (1)
- Explain how the following factors affect the rate of photosynthesis:
a) Concentration of carbon (IV) oxide
b) Light intensity (Solved)
Explain how the following factors affect the rate of photosynthesis:
a) Concentration of carbon (IV) oxide
b) Light intensity
Date posted: May 1, 2017. Answers (1)
- Name the sites where light and dark reactions of photosynthesis take place(Solved)
Name the sites where light and dark stages of photosynthesis take place
Date posted: May 1, 2017. Answers (1)
- How is the epidermis of a leaf of a green plant adapted to its function?(Solved)
How is the epidermis of a leaf of a green plant adapted to its function?
Date posted: May 1, 2017. Answers (1)
- (a) State the factors that affect enzymatic activities (b) Explain how one of the factors stated in (a) above affects enzymatic activities(Solved)
(a) State the factors that affect enzymatic activities (b) Explain how one of the factors stated in (a) above affects enzymatic activities
Date posted: May 1, 2017. Answers (1)
- Describe what happened during the light stage of photosynthesis(Solved)
Describe what happened during the light stage of photosynthesis
Date posted: May 1, 2017. Answers (1)
- Name the end products of the light stage in photosynthesis (Solved)
Name the end products of the light stage in photosynthesis
Date posted: May 1, 2017. Answers (1)
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What is the role of the vascular bundles in plant nutrition?
Date posted: May 1, 2017. Answers (1)
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Name two mineral elements that are necessary in the synthesis of chlorophyll
Date posted: May 1, 2017. Answers (1)
- Name the: a) Material that strengthens xylem tissue.
b) Tissue that is removed when the bark of a dicotyledonous plant is ringed.(Solved)
Name the: a) Material that strengthens xylem tissue.
b) Tissue that is removed when the bark of a dicotyledonous plant is ringed.
Date posted: May 1, 2017. Answers (1)
- State one effect of magnesium deficiency in green plants.(Solved)
State one effect of magnesium deficiency in green plants.
Date posted: May 1, 2017. Answers (1)