Pollination
A. Name the following:
1. The colourful and reproductive part of a plant:
= Flower.
2. The various parts of a flower:
= Calyx, Corolla, Androecium, Gynoecium.
3. The whorl that protects the flower in its bud stage:
= Calyx.
4. The long and slender part of the stamen:
= Filament.
5. The female reproductive unit of the gynoecium:
= Carpels or Pistils.
6. Flowers that contain both stamen and pistil:
= Bisexual Flowers.
7. Brightly coloured, scented leaf-like structures that attract insects towards the flower:
= Petals.
8. Dust-like particles that contain the male reproductive cells of a plant:
= Pollen grains.
9. transfer of pollen grains from the anther to the stigma of the same flower:
= Pollination.
B. Choose the correct option:
1. Which of the following is not the part of a flower?
a. Corolla. [ ]
b. Calyx. [ ]
c. Stamen. [ ]
d. Petiole. [✓]
2. Which of the following present inside the anther of a stamen?
a. Pollen grains. [✓]
b. Male reproductive cells. [ ]
c. Male gametes. [ ]
d. All are correct. [ ]
3. Stigma receives
a. Style. [ ]
b. Pollen grains. [✓]
c. Ovules. [ ]
d. Seeds. [ ]
4. Which of the following is not an example of a monosexual flower?
a. Hibiscus flower. [✓]
b. Papaya flower. [ ]
c. Pumpkin flower. [ ]
d. Watermelon flower. [ ]
5. Pollination leads to the formation of
a. Ovules. [ ]
b. Seeds. [✓]
c. Male gametes. [ ]
d. None of these. [ ]
C. Choose the correct option to fill in the blanks:
1. The outermost whorl of the flower is Sepals(Sepals/Petals).
2. The Anther(anther/Filament) is present at the tip of the stamen.
3. The Stigma(Style/Stigma) is the sticky, swollen tip of the pistil that receives the pollen grains.
4. After fertilization, the Ovary(Ovary/Style) forms the fruit.
D. Short answer questions:
1. What are the two reproductive parts of a flower?
= Two reproductive parts of a flower are - the male reproductive parts - stamen; and the female reproductive part pistil.
2. What is the importance of corolla present in a flower?
= Corolla consists of brightly coloured petals which attract insects that help in pollination. They produce different scents to attract insects towards the flower.
3. Mention the various parts of the the androecium.
= The various parts of the androecium are - stamens, filament, anther and pollen grains.
4. What is a bisexual flower?
= The flowers which have both the male and female reproductive parts stamen and pistil of the plant. Example - tulip, rose and hibiscus etc;
5. Define unisexual flower with examples.
= If a flower that possess either stamens or carpels but not both are called unisexual flower. Example - watermelon, pumpkin, cucumber and papaya etc;
E. Long answer questions:
1. Write a paragraph on parts of a flower.
= A flower has four parts - calyx, corolla, androecium and gynoecium.
i) Calyx:- It is the outermost whorl which contains a set of green leaf like structure called sepals. It protects the flower in the bud stage. They can also prepare food for the plant.
ii) Corolla:- It consists of a ring of brightly coloured leaf like structure called petals. They attract insects that help in pollination.
iii) Androecium:- It is the collection of stamens. Each stamen has a long slender stalk called filament. An anther is present at the tip of the stamen. Anthers produce dust like particles called pollen grains. It is the male reproductive unit of a plant.
iv) Gynaecium:- It is a collection of the female reproductive units called pistils. A pistil has three parts - stigma, style and ovary. Stigma is the sticky swollen tip of the pistil. Style is a thin long tube like structure that it connects the stigma to the ovary. Ovary is the swollen base of the pistil. The ovary forms the fruit of the plant, whereas the ovules form the seeds.
2. Define pollination. Also mention the two types of pollination.
= The transfer of pollen grains from anther to the stigma by various agencies called pollination.
There are two types of pollination -
i) Self pollination; and ii) Cross pollination.
i) Self pollination:- When the pollen grains from the anther of one flower fall on the stigma of the same flower or of another flower present on the same plant, the process is called self pollination.
ii) Cross pollination:- When pollen grains from the anther of one flower transferred to the stigma of another flower present on a different plant of the same kind, the process is called cross pollination.
F. State whether the following statements are true or false:
1. The outermost whorl of a flower is called the corolla. [F]
2. The androecium is called the male reproductive part of a plant. [T]
3. A pistil has three parts - stigma, style, and ovary. [T]
4. Tulip is an example of a monosexual flower. [F]