(i) Protandry - Male reproduction organ/anthers androecia/ stamens mature earlier than female reproduction organ/ carpels/ stigma/ pistil/ gynoecium in a flower.
(ii) Self sterility - pollen grains are sterile to stigma of the same plants or same flowers.
johnmulu answered the question on May 9, 2017 at 07:47
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The diagram below illustrates the structure of the female part of a flower.
(Solved)
The diagram below illustrates the structure of the female part of a flower.
(a) Name the part labelled W.
(b) Describe what happens when pollen tubes enters the structure labelled V
(c) What do structures labelled R and T develop into after fertilization?
Date posted:
May 9, 2017
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Answers (1)
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The photomicrographs below show the various stages of cell division in a certain plant
(Solved)
The photomicrographs below show the various stages of cell division in a certain plant
(a) (i) Name the type of cell division illustrated.
(ii) Give a reason for your answer in (a) (i) above.
(b)(i) Name the stage of cell division labelled K.
(ii) Give a reason for your answer in (b) (i) above.
Date posted:
May 9, 2017
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Answers (1)
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State four characteristics of fruit dispersed by animals.
(Solved)
State four characteristics of fruit dispersed by animals.
Date posted:
May 9, 2017
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Answers (1)
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The diagram below illustrates a growing pollen tube.
(Solved)
The diagram below illustrates a growing pollen tube.
(a) Name the part labeled B.
(b) Explain the role of the parts labeled A.
Date posted:
May 9, 2017
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Answers (1)
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Name the flower part that produces gametes.
(Solved)
Name the flower part that produces gametes.
Date posted:
May 9, 2017
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Answers (1)
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Name three mechanisms that ensure cross pollination takes place in flowering plants.
(Solved)
Name three mechanisms that ensure cross pollination takes place in flowering plants.
Date posted:
May 9, 2017
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Answers (1)
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The diagram below represents an experimental set-up used by students to investigate a certain process.
(Solved)
The diagram below represents an experimental set-up used by students to investigate a certain process.
Flower Q produced seeds while P did not. Account for the results.
Date posted:
May 9, 2017
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Answers (1)
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The diagram below represent a transverse section of an ovary from a certain flower.
(Solved)
The diagram below represent a transverse section of an ovary from a certain flower.
(i) Name the structure labeled W.
(ii) Name the type of placentation illustrated in this diagram
Date posted:
May 9, 2017
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Answers (1)
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Distinguish between protandry and protogyny
(Solved)
Distinguish between protandry and protogyny
Date posted:
May 9, 2017
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Answers (1)
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The diagram below shows a stage in mitosis in a plant cell.
(Solved)
The diagram below shows a stage in mitosis in a plant cell.
(a) Name the stage of mitosis.
(b) Give two reasons for your answer in (a) above
(c) Name the part of the plant from which the cell used in preparation was obtained.
Date posted:
May 9, 2017
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Answers (1)
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Name the part of the flower that develops into (a) Seed (b) Fruit
(Solved)
Name the part of the flower that develops into (a) Seed (b) Fruit
Date posted:
May 9, 2017
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Answers (1)
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(a) What is meant by the terms (i) Epigynous flower (ii) Staminate flower
(b) How are the male parts of wind pollinated flowers adapted to their function?
(Solved)
(a) What is meant by the terms (i) Epigynous flower (ii) Staminate flower
(b) How are the male parts of wind pollinated flowers adapted to their function?
Date posted:
May 9, 2017
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Answers (1)
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How do the male gamete nuclei reach the ovule after pollen grains land on the stigma?
(Solved)
How do the male gamete nuclei reach the ovule after pollen grains land on the stigma?
Date posted:
May 9, 2017
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Answers (1)
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Name the parts of the flower that are responsible the production of gametes.
(Solved)
Name the parts of the flower that are responsible the production of gametes.
Date posted:
May 9, 2017
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Answers (1)
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State two disadvantages of self-pollination
(Solved)
State two disadvantages of self-pollination
Date posted:
May 9, 2017
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Answers (1)
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A flower was found to have the following characteristics:
Inconspicuous petals
Long feathery stigma
Small, light pollen grains
(a) What is the likely agent of pollination of the flower?
(b) What is the significance of the flower?
(Solved)
A flower was found to have the following characteristics:
Inconspicuous petals
Long feathery stigma
Small, light pollen grains
(a) What is the likely agent of pollination of the flower?
(b) What is the significance of the flower?
Date posted:
May 9, 2017
.
Answers (1)
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State three characteristics that ensures cross-pollination takes place in flowering plants.
(Solved)
State three characteristics that ensures cross-pollination takes place in flowering plants.
Date posted:
May 9, 2017
.
Answers (1)
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Name two benefits that a parasite derives from the host
(Solved)
Name two benefits that a parasite derives from the host
Date posted:
May 8, 2017
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Answers (1)
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(a) Name the organism that: (i) Causes malaria; (ii) Transmits malaria
(Solved)
(a) Name the organism that: (i) Causes malaria; (ii) Transmits malaria
(b) State two control measures for malaria.
Date posted:
May 8, 2017
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Answers (1)
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Name the process through which free atmospheric nitrogen is converted into nitrates
(Solved)
Name the process through which free atmospheric nitrogen is converted into nitrates
Date posted:
May 8, 2017
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Answers (1)