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प्रश्न
What are the agents for pollination?
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उत्तर
Pollination occurs with the help of abiotic agents (wind, water) and biotic agents (insects and other animals).
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संबंधित प्रश्न
Match the following:
| Column A | Column B |
| (i) Stigma | (a) Neuron |
| (ii) Pepsin | (b) Carpel |
| (iii) Dendrites | (c) Protein |
| (d) Stamen |
What is pollination?
A student while observing an embryo of a pea seed in the laboratory listed various parts of the embryo as given below:
Testa, Tegmen, Radicle, Plumule, Micropyle, Cotyledon.
On examining the list the teacher remarked that only three parts are correct. Select three correct parts from the above list:
(a) Testa, Radicle, Cotyleddon
(b) Tegmen, Radicle, Micropyle
(c) Cotyledon, Plumule, Testa
(d) Radicle, Cotyledon, Plumule
Mention the changes a flower undergoes after fertilisation.
Mature ovary forms the ______.
What is the name of female part of a flower?
Fill in the following blank with suitable word :
The male organ of reproduction in the flower is the.......... .
Explain the terms 'self pollination'
How do the insects help in cross-pollination?
How is the process of pollination different from fertilization?
Name the part of a seed which grows into shoot.
Which of the following statements are true for flowers?
(i) Flowers are always bisexual.
(ii) They contain sexual reproductive organs.
(iii) They are produced in all groups of plants.
(iv) after fertilization they give rise to fruits.
One of the following occurs in the reproductive system of flowering plants as well as that of humans. This is :
(a) vas deferens
(b) anther
(c) ovary
(d) style
When an insect sits on the flower of a plant then some particles A present in the top of little stalks in the flower attach to its body hair. When this insect now sits on the flower of another similar plant, then particles A attached to the hair of insect are put on the top of a flask-shaped organ at the centre of flower. The particle A grows a long tube b from the top of flask-shaped organ through which C moves down and reaches the bottom part of flask-shaped organ. Here C fuses with the nucleus of d contained in structure E. the fusion of C and D forms a new cell f which grows and develops into a seed of the plant.
(a) What are particles A? What is the process of transferring A from one flower to another flower of similar plant by the insect known as?
(b) What is the name of tube B?
(c) What is C which moves down through the tube B?
(d) Name D and E.
(e) What is F?
In what ways is fertilisation in a plant similar to fertilisation in a human?
Put a tick mark (✓) against the correct alternative in the following statement
Reproductive whorls of a flower are:
Fill in the blanks:
A stamen consists of ______ and ________.
State whether the following statement is true (T) or false (F):
Stamens make egg cells.
Mention the function of Stigma.
Identify A, B, C and D in the given diagram and write their names.
__________ is present in unisexual flower.
Find an odd one out.
Give scientific reason.
Flower is a structural unit of sexual reproduction in plants.
Draw a neat and labelled diagram.
Double fertilization in angiosperms
Observe the figure below. Write functions of the labelled parts.
Match the following
| 1. | Petal | Opuntia |
| 2. | Fern | Chrysanthemum |
| 3. | Phylloclade | Attracts insect |
| 4. | Hooks | Spore |
| 5. | Sucker | Bignonia |
Write the events involved in the sexual reproduction of a flowering plant.
a. Discuss the first event and write the types.
b. Mention the advantages and the disadvantages of that event.
The ovule of an angiosperm is technically equivalent to ______
Antipodal cells are present towards the ______ in an anatropous ovule.
Which of the following is the outermost protective layer of anther?
Generally, in a pollen tube, which of the following moves to the tip of the tube?
Identify the female gametophyte in angiosperms.
In a bisexual flower inspite of the young stamens being removed artificially, the flower produces fruit. Provide a suitable explanation for the above situation.
State the number of sets of chromosomes present in a zygote.
Double fertilization is essential for formation of ______.
- Assertion: Primary endosperm nucleus is diploid.
- Reason: It is the product of double fertilisation.
