Basic Science Solutions for Class 7 Science Chapter 12 Reproduction In Plants are provided here with simple step-by-step explanations. These solutions for Reproduction In Plants are extremely popular among Class 7 students for Science Reproduction In Plants Solutions come handy for quickly completing your homework and preparing for exams. All questions and answers from the Basic Science Book of Class 7 Science Chapter 12 are provided here for you for free. You will also love the ad-free experience on Meritnation’s Basic Science Solutions. All Basic Science Solutions for class Class 7 Science are prepared by experts and are 100% accurate.

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The various ways in which plants reproduce asexually are:
(i) spore formation
(ii) budding
(iii) vegetative propagation

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The transfer of pollen grains from the anther to the stigma is called pollination.

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After fertilisation, the ovary becomes a fruit.

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Jasmine is one plant in which the seeds disperse by the explosion of fruit.

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The seeds need to be dispersed, so that they do not fall right next to the parent plant. If they fall in the vicinity of the parent plant, they will be deprived of sunlight and nutrients because they will have to compete for these resources, with the parent plant.

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Vegetative reproduction is the type of reproduction in which a new plant is produced from parts of plant, other than the vegetative parts. It is called vegetative propagation because it is extensively used commercially to grow or propagate those plants which reproduce vegetatively.

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The petals of flowers are brightly and beautifully coloured which attract insects. When the anthers of flowering plants mature, they burst open to release the pollen grains. When insects sit on these flowers, the pollen grains stick to their bodies. Then when they sit on other flowers, these pollen grains get transferred to the stigma of those flowers thus carrying out pollination.

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The plants that depend on wind for pollination, produce small flowers. These flowers produce numerous, small pollen grains. Being light-weighted, they are easily carried away by the wind. Their large number ensures that even if some of these pollen grains are lost in the wind, it would not hinder pollination. The female flowers have long and feathery stigma to catch these pollen grains dispersed by the wind.



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Unisexual flowers are those flowers that have either the male part or the female part. No, self-pollination is not possible in such flowers. Example of a unisexual flower is maize.

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Self Pollination Cross Pollination
The process in which the pollen grains from anthers of the same flower get transferred to the stigma of that flower is called self pollination. In cross pollination, the pollen grains of one flower get transferred to the stigma of a different flower of either the same or a different plant.
It is a feature of bisexual flowers. This is common in unisexual flowers.

Different plants have developed different mechanisms to prevent pollen grains from other flowers from reaching the stigma of their flowers. For example, flowers of the fig plant remain close untill pollination occurs. Similarly, flowers of plants such as peas, beans etc., are designed in such a way that the entry of pollen grains from other plants is not possible.

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The pollen grain, on reaching the stigma, grows a thin and long tube called the pollen tube to make its way through the style of the flower. The male gamete travels through this tube to reach the ovary to fertilise the female gamete, the egg. On reaching the ovary, the male gamete fuses with the egg to form a zygote. The ovule becomes a seed and the ovary becomes a fruit.

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Plants have developed various mechanisms to disperse their seeds. The plants which rely on animals for seed dispersal have bristles or hooks, which help the seed cling to the fur of the animals. When the animals move away, they are carried away from the parent plant.

The plants which rely on the wind for seed dispersal have winged and light-weight seeds. In some plants such as cotton, the seeds have hair-like fibres attached to them, which help them to get carried away with the wind.

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1. Ferns and mosses reproduce by spore formation.
2. The fusion of the male and the female gametes is called fertilisation.
3. The dark radiating rows under the head of a mushroom are called gills.
4. The single cell formed after the fusion of the male and the female gametes is called the zygote.
5. After fertilisation, the ovule develops into the seed.

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(c) The rapidly reproducing yeast cells release carbon dioxide due to respiration.
When yeast is added to the dough, it rises because the rapidly reproducing yeast cells release carbon dioxide during respiration.

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(a) bulbs
The underground stems of garlic and onion are called bulbs.

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(b) spores
Spores have thick walls to protect themselves from adverse conditions.

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(c) stem cuttings
Rose and lemon are grown from stem cuttings.

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(a) asexual reproduction
Here, vegetative propagation or spore formation cannot be the answer because they are only  types of asexual reproduction and do not cover the other types of asexual reproduction such as budding.



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