An experiment was carried out to determine the growth rates of bamboo and a variety of maize plants in two adjacent plots.The average height and...

An experiment was carried out to determine the growth rates of bamboo and a variety of maize plants in two adjacent plots.The average height and average dry weight of plants from the two populations were determined over a period of twenty weeks. The data is as shown in the table below.

(a) Between which two weeks did the greatest increase in weight occur in:
(i) Bamboo plants:
(ii) Maize plants:
(b) (i) Which of the two types of plants had a higher productivity by the end of the experiment?
(ii) Give a reason for your answer in (b) (i) above.
(c) Between weeks 14 and 18, the average height of the maize plants remained constant while average dry weight increased.Explain this observation.
(d) Suggest how the change in the average dry weight bamboo and maize plants would have been at week 22 if the experiment was continued.
(e) Why was it appropriate for this experiment to use:
(i) Dry weight instead of fresh weight.
(ii) Weight and height.
(f) Describe how the average height and weight of the plants were determined in this experiment.
(i) Average height.
(ii) Average dry weight.
(g) Give a reason why secondary thickening does not occur in bamboo and maize plants.

(a) (i) Bamboo plants; 4 and 6
(ii) Maize plants; 12 and 14;
(b) (i) Bamboo;
(ii) It had accumulated more weight and therefore greater dry weight;
(c) Maize plants have reached maturity / maximum height; food being manufactured (in green parts); is utilized for development of fruits and stored in the primary endosperm of the seeds;
(d) Increase in weight of bamboo; while that of maize decrease;
(e) (i) Dry weight instead of fresh weight
Fresh weight is dependent on the amount of water present in the plants; and this fluctuates depending on environment factors;
(ii) Weight and height Both gave a better measure / parameters of growth;
(f) Average height At every 2 weeks measure the height of samples of plants in each plot;Divide the total height by the number of plants in each plot; Average dry weight Harvest the sample measure of the plans in each plot; dry to constant weight; And divide by the number of plants;
(g) Being monocots / lack (inter) fascicular cambium;

---

sharon kalunda answered the question on September 16, 2019 at 09:10

Exams With Marking Schemes

• Grade 1
• Grade 2
• Grade 3
• Grade 4
• Grade 5
• Grade 6
• Grade 7
• Grade 8
• Grade 9
• PP1
• PP2
• Playgroup
• Form 1
• Form 2
• Form 3
• Form 4

Related Questions

• The equation below represents a certain physiological process. Study it and answer the questions below. (Solved)
  

  The equation below represents a certain physiological process. Study it and answer the questions below.
  
  (i) Name the above process.
  (ii) Give two reasons for question (i) above.
  (iii) Calculate the respiratory quotient of the compound that was as the substrate.
  (iv) Identify the substrate being respired in the above equation.
  (v) State one importance of this process to living organisms.
  (vi) Name the organelle where the above process takes place in animal cells.

  Date posted: September 16, 2019 .    Answers (1)

• A man with normal skin colour got married to a woman with normal skin colour. They gave birth to three children; one of them an... (Solved)
  

  A man with normal skin colour got married to a woman with normal skin colour. They gave birth to three children; one of them an albino.
  (a) Identify the probable genotype of the parents using letter (A) for normal gene and (a) for defective gene.
  Man:
  Woman:
  (b) Using a genetic cross; show the genotypes of the offspring.
  (c) Give the phenotypic ratio of the offsprings.

  Date posted: September 16, 2019 .    Answers (1)

• Name the source of hydrochloric acid in the mammalian heart. (Solved)
  

  Name the source of hydrochloric acid in the mammalian heart.

  Date posted: September 16, 2019 .    Answers (1)

• The chemical equation below represents a physiological process that takes place in living organisms. (Solved)
  

  The chemical equation below represents a physiological process that takes place in living organisms.
  
  Name:
  (i) The process R:
  (ii) Substance Q:

  Date posted: September 16, 2019 .    Answers (1)

• Explain why tracheids are not efficient in transporting water up the plant. (Solved)
  

  Explain why tracheids are not efficient in transporting water up the plant.

  Date posted: September 16, 2019 .    Answers (1)

• The figures below represent mammalian tissue as seen under a light microscope. (Solved)
  

  The figures below represent mammalian tissue as seen under a light microscope.
  
  (a) Identify the tissue
  (b) Name the cells represented by R,S and T
  (c) State the function of structure S and R.
  (d) Explain two adaptations of structure T to its function.
  (e) Name the hereditary condition a person with structure T is suffering from.

  Date posted: September 16, 2019 .    Answers (1)

• State the role of carnassial teeth in a lion.. (Solved)
  

  State the role of carnassial teeth in a lion..

  Date posted: September 16, 2019 .    Answers (1)

• The diagram below shows two potted plants on a laboratory bench near a window. (Solved)
  

  The diagram below shows two potted plants on a laboratory bench near a window.
  
  a) State one observable difference between the plants I and II.
  b) State the importance of the process that is seen in plant I.
  c) Explain the process that resulted to appearance of the leaves as in plant I above.
  d) Suppose a cell from a leaf of each of the plants I and II is mounted and observed under a microscope. Draw a diagram of a cell from each of the plants leaves.

  Date posted: September 16, 2019 .    Answers (1)

• The diagram below represents microvilli on epithelial cells (Solved)
  

  The diagram below represents microvilli on epithelial cells
  
  (a) Name the parts A and C
  (b) Name two parts in the human body where the above epithelial cells are found.

  Date posted: September 16, 2019 .    Answers (1)

• During an ecological study of a lake, a group of students recorded the following observations. (Solved)
  

  During an ecological study of a lake, a group of students recorded the following observations.
  (i) Planktonic crustaceans feed on planktonic algae;
  (ii) Small fish feed on planktonic crustaceans, worms and insect larvae;
  (iii) Worms feed on insect larvae;
  (iv) A bird species feeds on small fish, planktonic crustaceans, worms and large fish;
  (v) Insect larvae feed on planktonic algae;
  (vi) Large fish feed on small fish.
  (a) From this record of observations, construct a food web.
  (b) From the food web, isolate and write down a food chain that ends with:-
  (i) Bird species as a secondary consumer.
  (ii) Large fish as a tertiary consumer.
  (c) The biomass of the producers in the lake was found to be greater than that of primary consumers. Explain this observation.
  (d) Using the food web, identify three pairs of organisms that compete for food in the lake and for each case, name the food being competed for.
  (e) (i) State three ways by which human beings may interfere with this lake ecosystem.
  (i) Explain how each of the ways stated in (e) (i) above may affect life in the lake.

  Date posted: September 16, 2019 .    Answers (1)

• You are provided with photographs of animals. Study the photographs and the dichotomous key below to enable you identify the taxonomic group to which each... (Solved)
  

  You are provided with photographs of animals. Study the photographs and the dichotomous key below to enable you identify the taxonomic group to which each animal belongs.
  
  KEY
  1. a) Jointed legs present ………………………………………………………………go to 2
  b) Jointed legs absent………………………………………………………………..go to 7
  2. a) Three pairs of legs ………………………………………………………………..go to 3
  b) More than 3 pairs of legs………………………………………………………….go to 5
  3. a) Wings present …………………………………………………………………….go to 4
  b) Wings absent………………………………………………………………………Anoplura
  4. a) One pair of wings…………………………………………………………………Diptera
  b) Two pairs of wings……………………………………………………………Hymenoptera
  5. a) Four pairs of legs ………………………………………………………………… Arachnida
  b) More than ten pairs of legs ………………………………………………………. go to 6
  6. a) One pair of legs in each body segment…………………………………………… Chilopoda
  b) Two pairs of legs in each body segment ………………………………………… Diplopoda
  7. a) Body partially enclosed in a shell………………………………………………… Mollusca
  b) Body surface has spiny projection…………………………………………….Echinodermata
  a) Using the key, identify the following organisms to their taxonomic groups. In each case, give the sequence of steps which you followed in identifying them.
  
  b) i) Using observable features only, state the class to which the animal labeled A and B on the photographs above belong.State two observable features on B, that enabled you to arrive at that answer in (b) (i) above.

  Date posted: September 13, 2019 .    Answers (1)

• 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 .    Answers (1)

• 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 .    Answers (1)

• 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 .    Answers (1)

• 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 .    Answers (1)

• (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 .    Answers (1)

• 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 .    Answers (1)

• 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 .    Answers (1)

• 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 .    Answers (1)

• 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 .    Answers (1)