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प्रश्न
Give any two examples of agents of pollination.
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उत्तर
Examples of agents of pollination are:
- Insect pollination: Bees are the most common and recognized insect pollinators.
- Bird pollination: Plants are pollinated by some birds, particularly hummingbirds.
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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 |
Name the parts A, B and C shown in the diagram and write their functions.
How does fertilisation occur in flowers? Name the parts of the flower that develop into (i) seed, and (ii) fruit after fertilisation.
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
A student has to perform the experiment "To identify the different parts of an embryo of a dicot seed." Select from the following an appropriate group of seeds:
(a) Pea, gram, wheat
(b) Red kidney bean, maize, gram
(c) Maize, wheat, red kidney bean
(d) Red kidney bean, pea, gram
State significance of pollination.
The process of fusion of the male and female gametes is called ______.
Where are a plant's sex organs located?
Where is the male gamete formed in flowering plants?
Where is the female gamete formed in flowering plants?
What is made in anther of a flower?
Explain the terms 'self pollination'
Give some examples of different modes of fertilisation in nature?
In tobacco plant, the male gametes have 24 chromosomes.
What is the number of chromosomes in the female gamete?
What is meant by 'unisexual flowers' and 'bisexual flowers'? Give two examples of each.
Which of the following is the correct sequence of events of sexual reproduction in a flower?
(a) pollination, fertilisation, seed, embryo
(b) seed, embryo, fertilisation, pollination
(c) pollination, fertilisation, embryo, seed
(d) embryo, seed, pollination, fertilisation
The length of pollen tube depends on the distance between :
(a) pollen grain and upper surface of stigma
(b) pollen grain on upper surface of stigma and ovule
(c) pollen grain in anther and upper surface of stigma
(d) upper surface of stigma and lower part of style
Fill in the blanks:
A stamen consists of ______ and ________.
Draw a labelled diagram of a bisexual flower.
Give one example each of unisexual and bisexual flowers. Differentiate between the two types of pollination that occur in flowers. What happens when a pollen lands on a suitable stigma? Write about the events that occur till the seed formation in the ovary.
In the figure, the parts marked A, B and C are sequentially:
(A) Plumule, Radicle and Cotyledon
(B) Radicle, Plumule and Cotyledon
(C) Plumule, Cotyledon and Radicle
(D) Radicle, Cotyledon and Plumule
“Cell division is a type of reproduction in unicellular organism.” Justify.
Fill in the blank by selecting suitable word:
Transfer of pollen grains from the anther to the stigma is known as______________.
Write the functions of sepals
Give scientific reason.
Fertilization in plants is called double fertilization.
The male reproductive part of a flower is ______.
The essential parts of a flower are ______.
Which of the following is the outermost protective layer of anther?
Flowers showing ornithophily show few characteristic like ______.
In a bisexual flower inspite of the young stamens being removed artificially, the flower produces fruit. Provide a suitable explanation for the above situation.
Trace the path a male gamete takes to fertilise a female gamete after being released from the penis.
State the number of sets of chromosomes present in a zygote.
Sketch and label the essential and accessory whorls of flower.
What are the agents for pollination?
In flowering plants, the pollen grains are transferred to stigma by pollination but the female germ cells are present in the ovary.
Explain with the help of a labelled diagram (only concerned parts), how the male germ cell reaches the ovary.
