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Question
What are the agents for pollination?
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Solution
Pollination occurs with the help of abiotic agents (wind, water) and biotic agents (insects and other animals).
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RELATED QUESTIONS
(i) Name the part marked 'A' in the diagram.
(ii) How dose 'A' reachese part 'B'?
(iii) State the importance of the part 'C'.
(iv) What happens to the part marked 'D' after fertilisation is over?
You are asked by your teacher to study the different parts of an embryo of a gram seed. Given below are the steps to be followed for the experiment:
I. Soak the gram seeds in plain water and keep them overnight.
II. Cut open a soaked seed and observe its different parts.
III. Take some dry gram seeds in a petri dish.
IV. Drain the excess water.
V. Cover the soaked seeds with a wet cotton cloth and leave them for a day.
The correct sequence of these steps is :
(A) III, I, V, IV, II
(B) III, I, II, IV, V
(C) III, IV, V, I, II
(D) III, I, IV, V, II
How is the process of pollination different from fertilization?
The process of fusion of the male and female gametes is called ______.
Name the swollen lower part of the carpel.
Where are the pollen grains produced?
What is the name of female organ of a flower (other than carpel)?
Fill in the following blank with suitable word :
Pollen grains contain ............ gametes of a plant.
Fill in the following blank with suitable word :
The female organ of reproduction in the flower is the...........
Fill in the following blank with suitable word :
The term used to refer to the transfer of pollen from the stamen of one flower to the carpel of another flower of the same species is...........
What is made in anther of a flower?
What is meant by ‘unisexual flowers’?
Which among the following statements are true for unisexual flowers?
(i) They possess both stamen and pistil
(ii) They possess either stamen or pistil
(iii) They exhibit cross pollination
(iv) Unisexual flower possessing only stamens cannot produce fruits
(a) (i) and (iv)
(b) (ii), (iii) and (iv)
(c) (ii) and (iii)
(d) (i), (iii) and (iv)
| When an insect sits on the flower of a plant then somene 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. |
- 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?
- What is the name of tube B?
- What is C which moves down through the tube B?
- Name D and E.
- What is F?
Put a tick mark (✓) against the correct alternative in the following statement
Pollen is produced in the:
Fill in the blank by selecting suitable word:
A flower that bears both the male and the female parts is known as __________ flower.
Mention the function of Stigma.
What part is played by stamens and carpels in reproduction?
Write one main difference between asexual and sexual mode of reproduction. Which species is likely to have comparatively better chances of survival – the one reproducing asexually or the one reproducing sexually? Give reason to justify your answer.
The students of a class were asked by the teacher to study the different parts of an embryo of an angiosperm. Given below are the essential steps for the experiment :
A. Soak the seeds in plain water and keep them overnight.
B. Cut open the soaked seed and observe its different parts.
C. Take some healthy seeds in a petri-dish.
D. Drain the excess water, cover the seeds with a wet cotton cloth and leave them as it is for a day.
The correct sequence of these steps is
(a) C, A, D, B
(b) C, D, A, B
(c) A, C, D, B
(d) A, C, B, D
What is phototropism?
Explain sexual reproduction in plants.
Pollen grains are formed by _________ division in locules of anthers.
Pollen tube reaches the embryo sac via style.
Pollen grains from anther are transferred to the stigma.
What does germination mean?
Give scientific reason.
Flower is a structural unit of sexual reproduction in plants.
Observe the figure below. Write functions of the labelled parts.
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 anther wall consists of four wall layers where ______
Which of the following are the chemical components of the wall of pollen tube?
The 3-celled egg apparatus at the micropylar end comprises of ______
Flowers showing ornithophily show few characteristic like ______.
Pollen grains are produced by ______
Which among the following statements are true for sexual reproduction in flowering plants?
- It requires two types of gametes
- Fertilisation is a compulsory event
- It always results in formation of zygote
- Offspring formed are clones
Where is the zygote located in the flower after fertilization?
Sketch and label the essential and accessory whorls of flower.
State the post-fertilisation changes that lead to fruit formation in plants.
