Reproduction in Plants
Pollination: Sexual Reproduction
Parts of Flowers
Petal: Colored parts of the flower that attract insects and other pollinators.
- Sepal: Green, leaf-like structures that protect the flower bud.
-Stamen (Male Reproductive Organ):
- Filament: Long, thin stalk that supports the anther.
- Anther: Produces pollen grains (male gametes).
Pistil (Female Reproductive Organ):
- Stigma: Receives pollen grains during pollination.
- Style: Long, narrow tube that connects the stigma to the ovary.
- Ovary: Contains ovules (female gametes).
Pollination of Flowers
- Definition: Transfer of pollen grains from the anther to the stigma of the same or another plant.
- Types of Pollination:
- Self-Pollination: Pollination within the same plant.
- Cross-Pollination: Pollination between different plants.
- Process of Pollination:
1. A pollinator (e.g., insect, bird, wind) visits a flower in search of nectar or pollen.
2. As the pollinator moves from flower to flower, pollen grains from the anther of one flower stick to its body.
3. When the pollinator visits another flower, some of the pollen grains from its body are transferred to the stigma of the new flower.
- Agents of Pollination:
- Insects (e.g., bees, butterflies, moths): Most common pollinators.
- Birds: Some birds, like hummingbirds, feed on nectar and transfer pollen.
- Wind: Pollen grains can be blown from one flower to another by the wind.
- Bats: Some plants, like cacti and agave, are pollinated by bats.
Assessment Questions
1. What is pollination, and why is it important for plant reproduction?
2. Describe the structure of a flower, including the stamen and pistil.
3. What are the different types of pollination, and which agents are involved in each type?
Extension Activity
- Create a diagram of a flower, labeling its different parts.
- Research and write a short report on the importance of pollinators in plant reproduction.
EVALUATION
Here are ten objective questions on the topic "Pollination: Sexual Reproduction" with options lettered A to D:
1. What is the primary function of the petals in a flower?
A) To produce pollen grains
B) To attract insects and other pollinators
C) To protect the flower bud
D) To produce ovules
Answer: B) To attract insects and other pollinators
2. Which part of the flower produces pollen grains?
A) Stigma
B) Anther
C) Ovary
D) Sepal
Answer: B) Anther
3. What is the process called when pollen grains are transferred from one flower to another?
A) Fertilization
B) Pollination
C) Reproduction
D) Photosynthesis
Answer: B) Pollination
4. Which of the following is an example of a pollinator?
A) Wind
B) Insect
C) Rain
D) All of the above
Answer: D) All of the above (although rain is not a typical pollinator)
5. What is the name of the tube that connects the stigma to the ovary?
A) Style
B) Filament
C) Petal
D) Sepal
Answer: A) Style
6. Which type of pollination occurs within the same plant?
A) Cross-pollination
B) Self-pollination
C) Wind pollination
D) Insect pollination
Answer: B) Self-pollination
7. What is the name of the part of the flower that receives pollen grains during pollination?
A) Stigma
B) Anther
C) Ovary
D) Style
Answer: A) Stigma
8. Which of the following is NOT a type of pollination?
A) Self-pollination
B) Cross-pollination
C) Wind pollination
D) Water pollination
Answer: D) Water pollination (although some plants are pollinated by water, it is not a common type of pollination)
9. What is the primary function of the ovary in a flower?
A) To produce pollen grains
B) To produce ovules
C) To attract insects and other pollinators
D) To protect the flower bud
Answer: B) To produce ovules
10. Which of the following is an example of an agent that can transfer pollen grains during pollination?
A) Bat
B) Bird
C) Wind
D) All of the above
Answer: D) All of the above
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