Keywords To Remember
- Reproduction
The biological process by which living organisms produce offspring of their own kind. - Asexual Reproduction
A type of reproduction in which offspring are produced by a single parent without the involvement of gametes (sex cells). - Sexual Reproduction
A type of reproduction that involves two parents and the fusion of male and female gametes. - Budding
A form of asexual reproduction in which a new organism develops from an outgrowth or bud on the parent. - Fragmentation
A form of asexual reproduction where an organism breaks into parts, and each part develops into a new individual. - Spore Formation
A method of asexual reproduction involving the formation of spores that can develop into new individuals under suitable conditions. - Vegetative Propagation
A type of asexual reproduction in plants where new plants grow from the roots, stems, or leaves. - Pollination
The transfer of pollen grains from the anther to the stigma of a flower. - Fertilisation
The fusion of male and female gametes to form a zygote. - Seed Dispersal
The process by which seeds are spread away from the parent plant to reduce competition and promote growth. - Stamen
The male reproductive part of a flower, consisting of the anther and filament. - Pistil (Carpel)
The female reproductive part of a flower, consisting of the ovary, style, and stigma. - Anther
The part of the stamen where pollen grains are produced. - Filament
The stalk that supports the anther in the male part of the flower. - Ovary
The part of the pistil that contains the ovules; it develops into fruit after fertilisation. - Ovule
The structure inside the ovary that develops into a seed after fertilisation. - Zygote
The cell formed by the fusion of a male and female gamete. - Embryo
The young plant that develops from the zygote inside the seed. - Cotyledon
The part of a seed that stores food and provides nutrients to the growing embryo. - Unisexual Flower
A flower that has either stamens or pistils, but not both. - Bisexual Flower
A flower that contains both stamens and pistils. - Pollinators
Agents such as insects, wind, water, or animals that help in the transfer of pollen. - Self-Pollination
The transfer of pollen from the anther to the stigma of the same flower or a different flower on the same plant. - Cross-Pollination
The transfer of pollen from the flower of one plant to the stigma of a flower on another plant of the same species. - Fruit
The mature ovary of a flower, often containing seeds. - Seed
A plant embryo enclosed in a protective outer covering, capable of developing into a new plant. - Germination
The process by which a seed develops into a seedling under suitable conditions. - Tuber
A swollen underground stem, such as potato, used for storing nutrients and reproduction. - Rhizome
A horizontal underground stem that often sends out roots and shoots, as seen in ginger. - Bulb
A rounded underground storage organ composed of layered fleshy leaves, as in onion and tulip. - Corm
A short, thickened underground stem that stores food and helps in vegetative reproduction (e.g., colocasia). - Propagation
The act of multiplying or increasing the number of plants by natural or artificial means. - Grafting
An artificial vegetative propagation method where tissues of one plant are joined to another. - Layering
A method of vegetative propagation where a branch of the plant is bent and covered with soil to produce roots. - Cutting
A method of vegetative propagation where a part of the plant (stem, root or leaf) is cut and grown into a new plant. - False Fruit
A fruit that develops from parts of the flower other than the ovary (e.g., apple). - True Fruit
A fruit that develops only from the ovary after fertilisation. - Parthenocarpy
The development of fruit without fertilisation, resulting in seedless fruits. - Nectar
A sweet liquid produced by flowers to attract pollinators. - Receptacle
The part of a flower stalk where the parts of the flower are attached.
Something To Know
A. Fill in the blanks.
- ___________ reproduce through the process of budding.
Answer – Yeast
- Pollen grains are produced by ___________.
Answer – anther
- The agents, that carry the pollen grains from anther to a stigma, are called ___________ .
Answer – pollinators
- The fusion of a male gamete with a female gamete is called ___________.
Answer – fertilisation
- Seeds of orchids get dispersed by ___________.
Answer – wind
B. Write True or False for the following statements.
- Yeast reproduces asexually through fragmentation.
Answer – False (It reproduces by budding)
- Sweet potato and dahlia use their roots for asexual reproduction.
Answer – True
- A unisexual flower has both stamen and pistil in it.
Answer – False (It has either stamen or pistil)
- Water can be an agent of pollination.
Answer – True
- Male and female gametes fuse to form the zygote.
Answer – True
- Seeds of pea and bean plant are formed in pods.
Answer – True
C. Tick (✓) the correct option.
- Spirogyra reproduces asexually by—
fragmentation
spore formation
budding
vegetative propagation
Answer – fragmentation
- Bryophyllum reproduces through its—
roots
stem
leaves
flowers
Answer – leaves
- The reproductive part of the plant, for sexual reproduction, is its—
flower
stem
root
leaf
Answer – flower
- Pollen grains contain the—
future flower
male reproductive cell
future seed
female reproductive cell
Answer – male reproductive cell
- Fruit develops from the—
Ovary
ovule
leaves
petals
Answer – ovary
D. Answer the following questions in brief.
- Name the two types of reproduction in plants.
Answer – Asexual reproduction and Sexual reproduction.
- Define vegetative reproduction.
Answer – Vegetative reproduction is a form of asexual reproduction in which new plants grow from the vegetative parts of the plant such as roots, stems, or leaves.
- Give two examples of plants which reproduce through spore formation.
Answer – Fern and Fungi (e.g., Rhizopus).
- Name two artificial methods of vegetative propagation from stem.
Answer – Cutting and grafting.
- When is a flower said to be a bisexual flower?
Answer – A flower is said to be bisexual when it contains both male (stamens) and female (pistil) reproductive organs.
- Name any three ways by which seeds are dispersed.
Answer – By wind, by water, and by animals.
E. Answer the following questions
- In what ways is vegetative propagation better than sexual reproduction?
Answer – It is faster than sexual reproduction.
New plants are genetically identical to the parent.
It can be used to grow seedless plants.
Only one parent is needed.
- Draw a well labelled diagram to describe the parts of a flower.
Answer – (You may draw and label: Petal, Sepal, Anther, Filament, Stigma, Style, Ovary)
(Let me know if you want a labeled diagram image or sketch.) at your own.
- How is self pollination different from cross pollination?
Answer – Self-pollination: Pollen from the anther is transferred to the stigma of the same flower or another flower on the same plant.
Cross-pollination: Pollen is transferred to the stigma of a flower on a different plant of the same species.
- How are fruits formed?
Answer – After fertilisation, the ovary of the flower develops into a fruit, and the ovule inside becomes the seed.
- Why is dispersal of seeds necessary for growth of plants?
Answer – Seed dispersal helps reduce competition for sunlight, water, and nutrients among plants, and allows them to grow in new areas.
Value Based Question
Madam Anshita, a highly respected teacher, in a school for differently abled students, is a very hardworking, dedicated and disciplined teacher. She has a lot of empathy for her students. She uses different teaching methods as per the needs and requirements of her many, differently abled students. She often says that her approach is guided by nature which also uses different methods for dispersal of seeds of different types of plants.
- State the ‘values’ that have made Madam Anshita a highly respected teacher.
Answer – Dedication, empathy, discipline, hard work, and adaptability to students’ needs.
- Name the different methods that nature uses for dispersal of seeds. Give one example each of any two of these methods.
Answer – By wind – e.g., Dandelion
By water – e.g., Coconut
By animals – e.g., Xanthium
By explosion – e.g., Balsam
Something To Do
- Make a terrarium
Take a large glass bottle with a narrow mouth (wide enough to place plants inside the bottle). Fill the lower 1/6 part of the bottle with pebbles. Add a layer of sand, followed by leaf manure, and finally moss. Place plants, like aloe vera, money plant, cacti, in this terrarium. Keep the mouth of the bottle covered. You may open it for about an hour a day. Sprinkle some water once in 4-5 days. Your terrarium is ready. Decorate a sunny corner of your house with this terrarium.
Answer – (This is a hands-on activity. You can follow the steps mentioned in the instruction. Once done, describe it or take a photo for your school project.)
- Keep a few potatoes in a warm moist place for a few days. Observe the ‘eye’ portion that soon starts forming leaf like structures. Cut each potato into 3-4 pieces. Ensure that each piece has about 1-2 ‘eyes’. Bury these pieces in the soil. They will produce new potato plants within two weeks!
Answer – Observe potato reproduction from eyes (This shows how potatoes reproduce via vegetative propagation. Record observations like the number of days for sprouting and new leaf formation.)
- Visit a vegetable market. Make a list of the fruits and vegetables that you find there. Try to find out which of these vegetables are actually fruits (ripened ovaries).
List your observation in the following tabular format:
Name of the fruit/ vegetable Is it a ripened ovary? (true fruit) If no, which part of the plant is it?
Answer –
Name of the fruit/vegetable | Is it a ripened ovary? (true fruit) | If no, which part of the plant is it? |
Spinach | No | Leaves |
Cucumber | Yes | – |
Tomato | Yes | – |
Carrot | No | Root |
Apple | No | False fruit (develops from receptacle) |
Brinjal (Eggplant) | Yes | – |
Potato | No | Stem (tuber) |
Beans | Yes | – |
Onion | No | Bulb (modified stem) |
Pumpkin | Yes | – |
Additional Questions And Answers – 01
Fill in the Blanks (with Answers)
- The process by which living organisms produce more of their own kind is called __________.
Answer: reproduction - The flowers of a plant are the __________ parts.
Answer: reproductive - In asexual reproduction, an individual reproduces without the involvement of another __________ of the same species.
Answer: individual - Yeast reproduces asexually by a process called __________.
Answer: budding - The transfer of pollen grains from anther to stigma is called __________.
Answer: pollination - The male reproductive part of a flower is called the __________.
Answer: stamen - A flower with both stamens and pistils is called a __________ flower.
Answer: bisexual - Seeds are dispersed by wind, water, animals, or by __________ of fruits.
Answer: explosion - The fusion of male and female gametes is called __________.
Answer: fertilisation - Plants like Bryophyllum reproduce through __________ propagation by growing plantlets on their leaves.
Answer: vegetative
Multiple Choice Questions (MCQs) (with Answers)
- Which part of the plant is responsible for reproduction?
a) Roots
b) Stem
c) Leaves
d) Flowers
Answer: d) Flowers - Which of the following is NOT a method of asexual reproduction?
a) Budding
b) Fragmentation
c) Pollination
d) Spore formation
Answer: c) Pollination - Which part of the flower produces pollen grains?
a) Ovary
b) Stigma
c) Anther
d) Petal
Answer: c) Anther - What type of flower contains either only stamens or only pistils?
a) Bisexual
b) Unisexual
c) Hermaphrodite
d) Monoecious
Answer: b) Unisexual - Which of these is a vector (pollinator) for pollination?
a) Wind
b) Bees
c) Birds
d) All of the above
Answer: d) All of the above - Which plant reproduces through fragmentation?
a) Yeast
b) Spirogyra
c) Potato
d) Bryophyllum
Answer: b) Spirogyra - Which of the following seeds can be dispersed by water?
a) Coconut
b) Apple
c) Maple
d) Pea
Answer: a) Coconut
True/False Questions (with Answers)
- Sexual reproduction requires only one parent.
Answer: False - The stamen is the female reproductive part of a flower.
Answer: False - Seeds help plants spread to new areas to avoid competition.
Answer: True - Vegetative propagation produces plants that are genetically different from the parent.
Answer: False - Pollination can occur via wind, animals, or water.
Answer: True - Budding is a type of sexual reproduction.
Answer: False - Fertilisation occurs when male and female gametes fuse.
Answer: True
Short Questions (with Answers)
- Q: What is asexual reproduction?
A: Asexual reproduction is when an individual produces offspring without the involvement of another individual of the same species. - Q: Name two vegetative parts of a plant.
A: Roots and stem. - Q: What is the function of petals in flowers?
A: Petals attract insects for pollination by being bright and sometimes fragrant. - Q: What is pollination?
A: Pollination is the transfer of pollen grains from anther to stigma. - Q: Why is seed dispersal important?
A: It helps plants spread to new areas to reduce competition for resources. - Q: What is budding?
A: Budding is asexual reproduction where an outgrowth (bud) forms on the parent and detaches to become a new organism.
Competency-Based Questions (Reasoning & Assertion) (with Answers)
- Assertion (A): Vegetative propagation produces plants identical to the parent plant.
Reason (R): Vegetative propagation uses seeds to produce new plants.
a) Both A and R are true, and R is the correct explanation of A.
b) Both A and R are true, but R is not the correct explanation of A.
c) A is true, but R is false.
d) A is false, but R is true.
Answer: c) A is true, but R is false. (Vegetative propagation uses vegetative parts, not seeds.) - Assertion (A): Pollination always requires insects.
Reason (R): Pollen grains can be carried by wind and water as well.
a) Both A and R are true, and R is the correct explanation of A.
b) Both A and R are true, but R is not the correct explanation of A.
c) A is true, but R is false.
d) A is false, but R is true.
Answer: d) A is false, but R is true. - Assertion (A): All flowers have both male and female reproductive parts.
Reason (R): Some plants have unisexual flowers with either stamens or pistils.
a) Both A and R are true, and R is the correct explanation of A.
b) Both A and R are true, but R is not the correct explanation of A.
c) A is true, but R is false.
d) A is false, but R is true.
Answer: d) A is false, but R is true.
High Order Thinking Skill (HOTS) Questions (with Answers)
- Explain why vegetative propagation might be preferred over sexual reproduction in commercial farming.
Answer: Vegetative propagation is preferred because it produces plants faster, ensures desirable traits are preserved, and plants bear flowers and fruits earlier compared to seed-grown plants. - How does seed dispersal by animals benefit both the plants and the animals?
Answer: Animals get food from fruits, while plants benefit by having their seeds dispersed to new locations, reducing competition and increasing survival chances. - If a disease affects a crop propagated vegetatively, explain why the disease spreads faster than in seed-grown crops.
Answer: Vegetatively propagated plants are genetically identical, so a disease that affects one can easily infect all, while genetic variation in seed-grown plants can provide resistance. - How does fragmentation help algae like Spirogyra to colonize water bodies quickly?
Answer: When a filament breaks into fragments, each fragment grows into a new individual, rapidly increasing the population and covering the water surface.
Long Questions (50-60 words) (with Answers)
- Describe the process of pollination and explain its significance in sexual reproduction of flowering plants.
Answer: Pollination is the transfer of pollen grains from the anther to the stigma. It can be self-pollination or cross-pollination. Pollinators like insects, wind, and water assist this transfer. Pollination is essential for fertilisation, leading to seed and fruit formation, which helps plants reproduce sexually and produce offspring. - What is vegetative propagation? List three examples and their vegetative parts used for reproduction.
Answer: Vegetative propagation is a type of asexual reproduction where new plants grow from vegetative parts such as roots, stems, or leaves. Examples include potatoes from tubers (stem), onions from bulbs (stem), and sweet potatoes from roots. This method produces offspring identical to the parent plant. - Explain how seeds are dispersed by different agents and why seed dispersal is important for plants.
Answer: Seeds are dispersed by wind (e.g., drumstick), water (e.g., coconut), animals (e.g., apple), and explosion of fruits (e.g., pea pods). Seed dispersal helps plants spread to new locations, reducing competition for resources such as light, water, and nutrients, increasing their chances of survival.
Additional Questions And Answers – 02
Fill in the Blanks Questions and Answers
- Question: The process by which living organisms produce more of their own kind is called ______.
Answer: The process by which living organisms produce more of their own kind is called reproduction. - Question: The reproductive parts of a flowering plant are the ______.
Answer: The reproductive parts of a flowering plant are the flowers. - Question: In asexual reproduction, an individual reproduces without the involvement of another ______.
Answer: In asexual reproduction, an individual reproduces without the involvement of another individual. - Question: Yeast reproduces asexually through a process called ______.
Answer: Yeast reproduces asexually through a process called budding. - Question: Spirogyra reproduces asexually by ______.
Answer: Spirogyra reproduces asexually by fragmentation. - Question: Bread mould reproduces through the formation of ______.
Answer: Bread mould reproduces through the formation of spores. - Question: Vegetative propagation involves the use of ______ parts like roots, stem, or leaves.
Answer: Vegetative propagation involves the use of vegetative parts like roots, stem, or leaves. - Question: Potato tubers have ______ that grow into new plants.
Answer: Potato tubers have buds that grow into new plants. - Question: Sexual reproduction in plants requires the involvement of ______ individuals.
Answer: Sexual reproduction in plants requires the involvement of two - Question: The male reproductive part of a flower is the ______.
Answer: The male reproductive part of a flower is the stamen. - Question: The female reproductive part of a flower is the ______.
Answer: The female reproductive part of a flower is the pistil. - Question: Flowers with both stamens and pistils are called ______ flowers.
Answer: Flowers with both stamens and pistils are called bisexual - Question: The transfer of pollen grains from anther to stigma is called ______.
Answer: The transfer of pollen grains from anther to stigma is called pollination. - Question: Agents that transfer pollen grains are called ______.
Answer: Agents that transfer pollen grains are called pollinators. - Question: The fusion of male and female gametes in plants is called ______.
Answer: The fusion of male and female gametes in plants is called fertilisation. - Question: After fertilisation, the ovules develop into ______.
Answer: After fertilisation, the ovules develop into seeds. - Question: The ovary of a flower develops into a ______ after fertilisation.
Answer: The ovary of a flower develops into a fruit after fertilisation. - Question: Seeds of madar are dispersed by ______.
Answer: Seeds of madar are dispersed by wind. - Question: Coconuts are dispersed by ______.
Answer: Coconuts are dispersed by water. - Question: Some plants like castor disperse seeds through ______ of fruit.
Answer: Some plants like castor disperse seeds through explosion of fruit.
Multiple Choice Questions and Answers
- Question: What is reproduction in living organisms?
a) Movement of substances
b) Production of more of their own kind
c) Removal of wastes
d) Absorption of nutrients
Answer: b) Production of more of their own kind - Question: What are the reproductive parts of a flowering plant?
a) Roots
b) Stem
c) Flowers
d) Leaves
Answer: c) Flowers - Question: Which type of reproduction does not involve another individual?
a) Sexual reproduction
b) Asexual reproduction
c) Pollination
d) Fertilisation
Answer: b) Asexual reproduction - Question: How does yeast reproduce asexually?
a) Fragmentation
b) Spore formation
c) Budding
d) Vegetative propagation
Answer: c) Budding - Question: What type of asexual reproduction does Spirogyra use?
a) Budding
b) Fragmentation
c) Spore formation
d) Vegetative propagation
Answer: b) Fragmentation - Question: What structures on bread mould contain spores?
a) Buds
b) Sporangia
c) Filaments
d) Stems
Answer: b) Sporangia - Question: Which plant part is used in vegetative propagation of potatoes?
a) Leaves
b) Roots
c) Stem
d) Flowers
Answer: c) Stem - Question: What is a disadvantage of vegetative propagation?
a) Plants take longer to grow
b) Plants are identical and prone to disease
c) Plants do not bear flowers
d) Plants cannot produce seeds
Answer: b) Plants are identical and prone to disease - Question: What does sexual reproduction in plants require?
a) One individual
b) Two individuals
c) No individuals
d) Wind only
Answer: b) Two individuals - Question: What is the male reproductive part of a flower?
a) Pistil
b) Stamen
c) Sepal
d) Petal
Answer: b) Stamen - Question: What type of flower has both stamens and pistils?
a) Unisexual
b) Bisexual
c) Male flower
d) Female flower
Answer: b) Bisexual - Question: What is pollination in plants?
a) Fusion of gametes
b) Transfer of pollen from anther to stigma
c) Formation of seeds
d) Dispersal of seeds
Answer: b) Transfer of pollen from anther to stigma - Question: What are pollinators?
a) Seeds dispersed by wind
b) Agents that transfer pollen grains
c) Parts of a flower
d) Types of fruits
Answer: b) Agents that transfer pollen grains - Question: What happens during fertilisation in plants?
a) Pollen grains are dispersed
b) Male and female gametes fuse
c) Seeds are formed
d) Fruits explode
Answer: b) Male and female gametes fuse - Question: What develops into a fruit after fertilisation?
a) Ovule
b) Stamen
c) Ovary
d) Petal
Answer: c) Ovary - Question: What is the purpose of seed dispersal in plants?
a) To produce more flowers
b) To reduce competition for resources
c) To form fruits
d) To attract pollinators
Answer: b) To reduce competition for resources - Question: How are seeds of madar dispersed?
a) By water
b) By wind
c) By animals
d) By explosion
Answer: b) By wind - Question: Which plant’s seeds are dispersed by water?
a) Madar
b) Castor
c) Coconut
d) Xanthium
Answer: c) Coconut - Question: How do some plants like castor disperse seeds?
a) By wind
b) By explosion of fruit
c) By water
d) By insects
Answer: b) By explosion of fruit - Question: Which animal helps disperse Acacia seeds?
a) Bird
b) Elephant
c) Orangutan
d) Bat
Answer: b) Elephant
True/False Questions and Answers
- Question: Reproduction is the process by which organisms produce more of their own kind.
Answer: True - Question: The vegetative parts of a plant are the flowers.
Answer: False (Vegetative parts are roots, stem, and leaves.) - Question: Asexual reproduction involves two individuals.
Answer: False (It involves only one individual.) - Question: Yeast reproduces asexually by budding.
Answer: True - Question: Spirogyra reproduces by spore formation.
Answer: False (It reproduces by fragmentation.) - Question: Bread mould forms sporangia that contain spores.
Answer: True - Question: Vegetative propagation uses reproductive parts of a plant.
Answer: False (It uses vegetative parts like roots, stem, or leaves.) - Question: Plants produced by vegetative propagation are identical to the parent plant.
Answer: True - Question: Sexual reproduction in plants requires two individuals.
Answer: True - Question: The stamen is the female reproductive part of a flower.
Answer: False (It’s the male reproductive part.) - Question: Bisexual flowers have both stamens and pistils.
Answer: True - Question: Pollination is the fusion of male and female gametes.
Answer: False (It’s the transfer of pollen from anther to stigma.) - Question: Pollinators help transfer pollen grains in plants.
Answer: True - Question: Fertilisation in plants results in the formation of a zygote.
Answer: True - Question: After fertilisation, the ovules develop into fruits.
Answer: False (Ovules develop into seeds; the ovary develops into fruit.) - Question: Seed dispersal helps reduce competition among plants.
Answer: True - Question: Seeds of madar are dispersed by water.
Answer: False (They are dispersed by wind.) - Question: Coconuts are dispersed by animals.
Answer: False (They are dispersed by water.) - Question: Some plants disperse seeds by explosion of fruit.
Answer: True - Question: Elephants help disperse Acacia seeds through their droppings.
Answer: True
Short Questions and Answers
- Question: What is reproduction in living organisms?
Answer: Producing more of their own kind. - Question: What are the reproductive parts of a flowering plant?
Answer: Flowers. - Question: What is asexual reproduction?
Answer: Reproduction without another individual. - Question: How does yeast reproduce asexually?
Answer: By budding. - Question: What type of asexual reproduction does Spirogyra use?
Answer: Fragmentation. - Question: How does bread mould reproduce?
Answer: Through spore formation. - Question: What is vegetative propagation?
Answer: Asexual reproduction using vegetative parts. - Question: What is a disadvantage of vegetative propagation?
Answer: Plants are identical and prone to disease. - Question: What does sexual reproduction in plants require?
Answer: Two individuals. - Question: What is the male reproductive part of a flower?
Answer: Stamen. - Question: What is a bisexual flower?
Answer: A flower with both stamens and pistils. - Question: What is pollination?
Answer: Transfer of pollen from anther to stigma. - Question: What are pollinators?
Answer: Agents that transfer pollen grains. - Question: What happens during fertilisation in plants?
Answer: Male and female gametes fuse. - Question: What develops into a fruit after fertilisation?
Answer: Ovary. - Question: What is the purpose of seed dispersal?
Answer: To reduce competition for resources. - Question: How are madar seeds dispersed?
Answer: By wind. - Question: Which plant’s seeds are dispersed by water?
Answer: Coconut. - Question: How do some plants like castor disperse seeds?
Answer: By explosion of fruit. - Question: Which animal helps disperse Acacia seeds?
Answer: Elephant.
Competency-Based Questions and Answers (Reasoning and Assertion)
- Question: Assertion (A): Asexual reproduction does not involve another individual.
Reason (R): It allows an organism to reproduce on its own.
Answer: Both A and R are true, and R is the correct explanation of A. Asexual reproduction, as stated, involves only one individual, such as in yeast budding, allowing it to reproduce independently without another organism, ensuring rapid multiplication in favorable conditions, as seen in single-celled organisms. - Question: Assertion (A): Vegetative propagation produces identical plants.
Reason (R): It uses vegetative parts like roots, stem, or leaves.
Answer: A is true, but R is not the correct explanation of A. Vegetative propagation does use vegetative parts, as noted, but identical plants result because there’s no genetic variation, unlike sexual reproduction. This lack of variation explains why the offspring are exact copies of the parent plant. - Question: Assertion (A): Bisexual flowers can self-pollinate.
Reason (R): They have both stamens and pistils in the same flower.
Answer: Both A and R are true, and R is the correct explanation of A. Bisexual flowers, like those of tomato, have both stamens and pistils, as described, allowing pollen transfer within the same flower, enabling self-pollination without needing another flower, supporting reproduction in such plants. - Question: Assertion (A): Pollination is essential for sexual reproduction in plants.
Reason (R): It transfers pollen grains from anther to stigma.
Answer: Both A and R are true, and R is the correct explanation of A. Pollination, as stated, transfers pollen from anther to stigma, a crucial step for fertilisation in sexual reproduction, ensuring the male gamete reaches the ovule, leading to seed formation and plant reproduction. - Question: Assertion (A): Seed dispersal reduces competition among plants.
Reason (R): It spreads seeds away from the parent plant.
Answer: Both A and R are true, and R is the correct explanation of A. Seed dispersal, as noted, spreads seeds far from the parent plant, reducing competition for light, water, and nutrients among seedlings, ensuring better survival and growth opportunities for new plants in diverse locations. - Question: Assertion (A): Wind-pollinated flowers have bright petals.
Reason (R): Bright petals attract insects for pollination.
Answer: A is false, but R is true. Wind-pollinated flowers, as described, lack bright petals since they don’t rely on insects, unlike insect-pollinated flowers where bright petals attract pollinators. Wind-pollinated flowers have anthers at a higher level to release pollen into the air, not for insect attraction. - Question: Assertion (A): Some plants disperse seeds by explosion.
Reason (R): This method scatters seeds far from the parent plant.
Answer: Both A and R are true, and R is the correct explanation of A. Plants like castor, as mentioned, use fruit explosion to disperse seeds, scattering them far away, reducing competition with the parent plant and increasing the chances of survival in new areas with adequate resources. - Question: Assertion (A): Vegetative propagation is faster than sexual reproduction.
Reason (R): It does not involve pollination or fertilisation.
Answer: Both A and R are true, and R is the correct explanation of A. Vegetative propagation, as stated, skips pollination and fertilisation, directly producing new plants from vegetative parts, allowing faster growth and earlier flowering compared to sexual reproduction, which requires seed formation and germination. - Question: Assertion (A): Coconuts are dispersed by water.
Reason (R): They can float and travel across seas.
Answer: Both A and R are true, and R is the correct explanation of A. Coconuts, as noted, are dispersed by water because they can float, traveling thousands of kilometers across seas, enabling them to reach new shores and germinate, ensuring the spread of coconut palms in coastal regions. - Question: Assertion (A): Flowers dry up after fertilisation.
Reason (R): Their role in reproduction is complete.
Answer: Both A and R are true, and R is the correct explanation of A. After fertilisation, sepals, petals, and stamens dry up and fall off, as described, since their role in attracting pollinators and facilitating reproduction is done, allowing the ovary to develop into a fruit for seed protection.
High Order Thinking Skills (HOTS) Questions and Answers
- Question: Why might asexual reproduction be advantageous in stable environments, and what does this suggest about the role of genetic variation in plant survival?
Answer: Asexual reproduction, like budding in yeast, produces identical offspring quickly, thriving in stable environments without needing genetic variation, as noted. This suggests genetic variation is less critical in unchanging conditions—uniform traits ensure survival, but in changing environments, variation from sexual reproduction enhances adaptability, highlighting the balance between stability and diversity in plant survival. - Question: How does the structure of pollen grains support their role in pollination, and what does this indicate about the importance of structural adaptations in reproduction?
Answer: Pollen grains are light, microscopic, with tough outer walls, as described, enabling wind or insect transport during pollination. This indicates structural adaptations are crucial in reproduction—specialized features like resistant walls and small size ensure pollen reaches the stigma, facilitating fertilisation and ensuring successful reproduction in diverse environmental conditions for plants. - Question: Why might vegetative propagation be preferred for commercial plants, and what does this reveal about the balance between efficiency and diversity in agriculture?
Answer: Vegetative propagation ensures identical plants with desirable traits like flower color, as stated, making it ideal for commercial consistency in plants like roses. This reveals agriculture balances efficiency—uniform crops ensure predictable yields—but sacrifices diversity, as identical plants risk disease susceptibility, highlighting the trade-off between productivity and resilience in farming practices. - Question: How does seed dispersal by animals benefit both plants and animals, and what does this suggest about ecological relationships in nature?
Answer: Animals like elephants eat fruits, dispersing seeds like Acacia in droppings, as noted, helping plants spread while animals gain food. This suggests ecological relationships are mutualistic—plants benefit from wider distribution, reducing competition, while animals receive nutrition, showing how interdependent interactions in nature enhance survival and biodiversity across species in ecosystems. - Question: Why might wind-pollinated flowers lack bright petals, and what does this indicate about the role of energy allocation in plant reproduction?
Answer: Wind-pollinated flowers, like those described, lack bright petals since they don’t attract insects, relying on wind for pollen transfer. This indicates plants allocate energy efficiently—resources are used for pollen production, not petal color, optimizing reproduction in environments where wind is reliable, showing how plants adapt energy use to reproductive strategies. - Question: How does the explosion of fruit in some plants enhance seed dispersal, and what does this reveal about the diversity of reproductive strategies in plants?
Answer: Explosion in plants like castor scatters seeds far from the parent, as stated, reducing competition and increasing survival chances in new areas. This reveals the diversity of reproductive strategies—plants evolve varied dispersal methods like explosion, wind, or animals, adapting to their environment, ensuring effective reproduction and survival in different ecological niches. - Question: Why might identical plants from vegetative propagation be at risk, and what does this suggest about the importance of genetic diversity in plant populations?
Answer: Identical plants from vegetative propagation, as noted, are at risk because a disease can infect them all due to no genetic variation. This suggests genetic diversity is crucial—diverse traits from sexual reproduction enhance resistance to diseases and environmental changes, ensuring long-term survival and adaptability of plant populations in dynamic ecosystems. - Question: How does the structure of bisexual flowers support self-pollination, and what does this indicate about reproductive flexibility in plants?
Answer: Bisexual flowers, with stamens and pistils, as described, allow self-pollination within the same flower, ensuring reproduction without external agents. This indicates reproductive flexibility—plants can self-pollinate when pollinators are scarce, guaranteeing seed production, while also allowing cross-pollination for genetic diversity, showing how plants adapt to varying reproductive challenges in nature. - Question: Why might coconuts travel long distances by water, and what does this reveal about the role of dispersal in plant distribution?
Answer: Coconuts float and travel thousands of kilometers across seas, as stated, reaching new shores to germinate, expanding their range. This reveals dispersal’s role in plant distribution—long-distance travel ensures colonization of new areas, reducing competition and enabling survival in diverse habitats, highlighting how dispersal mechanisms shape plant geographic spread and ecosystem diversity. - Question: How does the activity of growing yeast demonstrate budding, and what does this suggest about the simplicity of asexual reproduction in microorganisms?
Answer: The yeast activity shows budding as cells form buds that grow and detach, observed under a microscope, as described, producing new cells rapidly. This suggests asexual reproduction in microorganisms is simple—budding requires minimal resources and no partner, enabling quick population growth, highlighting efficiency in stable conditions for single-celled organisms like yeast.
Long Questions and Answers (50-60 Words)
- Question: Describe the process of asexual reproduction by budding in yeast.
Answer: Yeast reproduces asexually by budding, forming an outgrowth called a bud, as stated. The nucleus divides, with one daughter nucleus moving into the bud, which grows and detaches from the parent cell. Sometimes, buds form chains, rapidly producing many yeast cells, demonstrating an efficient method of asexual reproduction in unicellular organisms like yeast. - Question: Explain how Spirogyra reproduces by fragmentation.
Answer: Spirogyra, an alga, reproduces by fragmentation, where its filament breaks into two or more fragments, as described. Each fragment grows into a new individual, continuing the process to cover areas like ponds with green scum. This asexual method allows rapid multiplication, ensuring survival in stagnant water bodies without needing complex reproductive structures or partners. - Question: Discuss the process of spore formation in bread mould.
Answer: Bread mould reproduces via spore formation, developing sporangia—pin-head structures containing spores, as noted in the activity. These thick-walled spores are carried by wind, germinating in suitable conditions to form new mould. This asexual method enables widespread dispersal and rapid growth on spoilt food, showcasing an efficient reproductive strategy for fungi in favorable environments. - Question: Describe vegetative propagation in potatoes.
Answer: Vegetative propagation in potatoes occurs through the stem, specifically tubers, as stated. Potato tubers have buds called ‘eyes’ that grow into new plants when planted. This asexual method ensures identical offspring, allowing faster growth and earlier flowering compared to seed-based reproduction, making it ideal for maintaining desirable traits in agricultural potato crops. - Question: Explain the process of pollination in flowering plants.
Answer: Pollination in flowering plants is the transfer of pollen grains from the anther to the stigma, as described. It can be self-pollination within the same flower or cross-pollination between flowers, facilitated by pollinators like wind, insects, or birds. This process is essential for fertilisation, enabling sexual reproduction and seed formation in plants. - Question: Discuss the role of pollinators in plant reproduction.
Answer: Pollinators like bees, butterflies, birds, and wind transfer pollen from anther to stigma, as noted, enabling fertilisation in sexual reproduction. Insect-pollinated flowers attract pollinators with bright petals and nectar, while wind-pollinated flowers release light pollen. Pollinators ensure genetic diversity through cross-pollination, supporting plant reproduction and survival across diverse environments. - Question: Describe what happens after fertilisation in a flower.
Answer: After fertilisation, the flower’s sepals, petals, and stamens dry up and fall off, as stated. The ovules develop into seeds containing the embryo, and the ovary grows into a fruit, which may be juicy or woody. This process protects seeds, aiding their dispersal and ensuring the continuation of the plant’s life cycle. - Question: Explain the importance of seed dispersal in plants.
Answer: Seed dispersal reduces competition for light, water, and nutrients by spreading seeds away from the parent plant, as described. Methods like wind, water, animals, or explosion ensure seedlings grow in new areas, enhancing survival chances. This process prevents overcrowding, supporting healthy growth and enabling plants to colonize diverse habitats effectively. - Question: Discuss how seeds are dispersed by wind.
Answer: Seeds dispersed by wind, like those of madar, are light with hairy growths acting as parachutes, as noted. This allows them to be carried far by air currents, reducing competition with the parent plant. Examples include maple and sunflower seeds, ensuring wide distribution and better survival in new locations with adequate resources. - Question: Describe how animals help in seed dispersal.
Answer: Animals like elephants and birds eat fruits, dispersing seeds through droppings, as stated. Seeds of Xanthium attach to animal fur with hooks, while elephants shake Acacia trees, spreading seeds. This method benefits plants by reducing competition and animals by providing food, ensuring plant spread to new areas for growth.