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Questions
Make a list of any three outbreeding devices that flowering plants have developed and explain how they help to encourage cross-pollination.
List any three outbreeding devices that flowering plants have developed for cross-pollination and explain how they help to encourage cross-pollination.
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Solution
- Dichogamy: Flowers are unisexual, so self-pollination is not possible. The plants may be monoecious, bearing both male and female flowers (e.g. maize), or dioecious, bearing male and female flowers on separate plants (e.g. mulberry, papaya).
- Prepotency: Pollen grains of another flower germinate more rapidly on the stigma than pollen grains of the same flower. Examples of this include apples and grapes.
- Self-sterility (Self-incompatibility): Pollen grains of a flower do not germinate on the stigma of the same flower because of the presence of similar self-sterile genes. Examples of this include tobacco, potatoes, and crucifers.
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RELATED QUESTIONS
A flower of tomato plant following the process of sexual reproduction produces 200 viable seeds.
Answer the following questions giving reasons :
(a) What would have been the minimum number of ovules present in pre-pollinated pistil ?
(b) How many microscope mother cells would minimally be required to produce requisite number of pollen grains ?
(c) How many pollen grains must have minimally pollinated the carple ?
(d) How many male gametes would have used to produce these 200 viable seeds ?
(e) How many megaspore mother cells were required in this process ?
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Give the floral adaptations for anemophily.
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Select and write the most appropriate answer from the given alternatives for the following subquestion:
A versatile anther is an adaptation for _______ type of pollination.
Type of interaction where an individual sacrifices its own welfare (life) for the benefit of another animal of its own species is ______.
Answer the following question.
Write the difference in the characteristics of the progeny produced as a result of the two processes.
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Put a tick mark (✓) against the correct alternative in the following statements
Vegetative propagation is not observed in:
Flowers which have single ovule in the ovary and are packed into inflorescence are usually pollinated by ______.
Anemophily type of pollination is found in ______.
Both chasmogamous and cleistogamous flowers are present in ______.
Which of the following is not a water pollinated plant?
Which type of pollination does the figure indicate?
In which one of the following pollination is autogamous?
Choose the correct statement from the following:
Pollination in water lilies is carried out by ______.
What is hypohydrophily?
Name the following:
Aquatic plants which are anemophilous.
