Following are the various methods of seed dispersal: • Dispersal by Wind: Seeds of some plants are light-weight and some hair-like or wing-like structures are present on them. Such seeds float on air and are thus dispersed by wind. Example: Dandelion, maple, drumstick, etc. • Dispersal by Water: DisRead more
Following are the various methods of seed dispersal:
• Dispersal by Wind: Seeds of some plants are light-weight and some hair-like or wing-like structures are present on them. Such seeds float on air and are thus dispersed by wind. Example: Dandelion, maple, drumstick, etc.
• Dispersal by Water: Dispersal by water takes place in some aquatic plants and in some which grow near a water body. Seeds of water lily float and thus dispersed by water. The coconut seed has a tough fibrous covering which has plenty of air inside. This helps the coconut seeds in floating on water.
• Dispersal by Animals: Some seeds have spine like structures on them. They get stuck to the fur of animals and thus get spread to different places. Examples; Beggar tick, Xanthium, etc. Some seeds are swallowed by birds and animals along with fruits. These seeds get dispersed with bird or animal droppings.
• Dispersal by Bursting: Some fruits burst open when they mature. The force of bursting is enough to spread the seeds. Examples; Ladyfinger, castor, balsam, etc.
• Dispersal by Humans: Human beings also help in dispersal of seeds, especially during farming.
The process of fusion of the male and the female gametes is called (i) fertilisation. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
The process of fusion of the male and the female gametes is called (i) fertilisation.
Once pollen grain spreads on the stigma, it produces a pollen tube. This process is called germination of pollen grain. The pollen tube penetrates the style and reaches the ovary. Male nucleus is transferred through this pollen tube. Finally, fusion of male and female nuclei takes place inside the oRead more
Once pollen grain spreads on the stigma, it produces a pollen tube. This process is called germination of pollen grain. The pollen tube penetrates the style and reaches the ovary. Male nucleus is transferred through this pollen tube. Finally, fusion of male and female nuclei takes place inside the ovary. This step is called fertilization.
Asexual Reproduction: 1. Only one parent is needed. 2. Offspring is normally similar to parent. 3. Yeast, hydra, spirogyra etc. show asexual reproduction. Sexual Reproduction: 1. Two parent (Male and female gametes) are required. 2. Offspring shows variation with respect to parent. 3. Animals, humanRead more
Asexual Reproduction:
1. Only one parent is needed.
2. Offspring is normally similar to parent.
3. Yeast, hydra, spirogyra etc. show asexual reproduction.
Sexual Reproduction:
1. Two parent (Male and female gametes) are required.
2. Offspring shows variation with respect to parent.
3. Animals, human, insects etc. show sexual reproduction.
When two parents are involved in reproduction, the method is called sexual reproduction. The male and female gametes fuse during fertilization to produce zygote. The zygote subsequently develops into an embryo which further develops into a new individual. https://www.tiwariacademy.com/ncert-solutionRead more
When two parents are involved in reproduction, the method is called sexual reproduction. The male and female gametes fuse during fertilization to produce zygote. The zygote subsequently develops into an embryo which further develops into a new individual.
Describe the various ways by which seeds are dispersed.
Following are the various methods of seed dispersal: • Dispersal by Wind: Seeds of some plants are light-weight and some hair-like or wing-like structures are present on them. Such seeds float on air and are thus dispersed by wind. Example: Dandelion, maple, drumstick, etc. • Dispersal by Water: DisRead more
Following are the various methods of seed dispersal:
• Dispersal by Wind: Seeds of some plants are light-weight and some hair-like or wing-like structures are present on them. Such seeds float on air and are thus dispersed by wind. Example: Dandelion, maple, drumstick, etc.
• Dispersal by Water: Dispersal by water takes place in some aquatic plants and in some which grow near a water body. Seeds of water lily float and thus dispersed by water. The coconut seed has a tough fibrous covering which has plenty of air inside. This helps the coconut seeds in floating on water.
• Dispersal by Animals: Some seeds have spine like structures on them. They get stuck to the fur of animals and thus get spread to different places. Examples; Beggar tick, Xanthium, etc. Some seeds are swallowed by birds and animals along with fruits. These seeds get dispersed with bird or animal droppings.
• Dispersal by Bursting: Some fruits burst open when they mature. The force of bursting is enough to spread the seeds. Examples; Ladyfinger, castor, balsam, etc.
• Dispersal by Humans: Human beings also help in dispersal of seeds, especially during farming.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
See lessBryophyllum can reproduce by its
Bryophyllum can reproduce by its (ii) leaves. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
Bryophyllum can reproduce by its (ii) leaves.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
See lessA spore producing plant is
A spore producing plant is (ii) bread mould. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
A spore producing plant is (ii) bread mould.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
See lessMature ovary forms the
Mature ovary forms the (iv) fruit. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
Mature ovary forms the (iv) fruit.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
See lessThe process of fusion of the male and the female gametes is called
The process of fusion of the male and the female gametes is called (i) fertilisation. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
The process of fusion of the male and the female gametes is called (i) fertilisation.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
See lessThe reproductive part of a plant is the
The reproductive part of a plant is the (iv) flower. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
The reproductive part of a plant is the (iv) flower.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
See lessHow does the process of fertilisation take place in flowers?
Once pollen grain spreads on the stigma, it produces a pollen tube. This process is called germination of pollen grain. The pollen tube penetrates the style and reaches the ovary. Male nucleus is transferred through this pollen tube. Finally, fusion of male and female nuclei takes place inside the oRead more
Once pollen grain spreads on the stigma, it produces a pollen tube. This process is called germination of pollen grain. The pollen tube penetrates the style and reaches the ovary. Male nucleus is transferred through this pollen tube. Finally, fusion of male and female nuclei takes place inside the ovary. This step is called fertilization.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
See lessState the main difference between asexual and sexual reproduction.
Asexual Reproduction: 1. Only one parent is needed. 2. Offspring is normally similar to parent. 3. Yeast, hydra, spirogyra etc. show asexual reproduction. Sexual Reproduction: 1. Two parent (Male and female gametes) are required. 2. Offspring shows variation with respect to parent. 3. Animals, humanRead more
Asexual Reproduction:
See less1. Only one parent is needed.
2. Offspring is normally similar to parent.
3. Yeast, hydra, spirogyra etc. show asexual reproduction.
Sexual Reproduction:
1. Two parent (Male and female gametes) are required.
2. Offspring shows variation with respect to parent.
3. Animals, human, insects etc. show sexual reproduction.
Explain what you understand by sexual reproduction.
When two parents are involved in reproduction, the method is called sexual reproduction. The male and female gametes fuse during fertilization to produce zygote. The zygote subsequently develops into an embryo which further develops into a new individual. https://www.tiwariacademy.com/ncert-solutionRead more
When two parents are involved in reproduction, the method is called sexual reproduction. The male and female gametes fuse during fertilization to produce zygote. The zygote subsequently develops into an embryo which further develops into a new individual.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
See lessSeed dispersal takes place by means of _____________, _____________ and _____________.
Seed dispersal takes place by means of wind, water and animal. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
Seed dispersal takes place by means of wind, water and animal.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-12/
See less