Reproduction in plants class 7 extra questions
Answers
1.What is meant by reproduction?
Ans: The process of producing new individuals of same kind of the same species is called reproduction.
2. Why reproduction is a essential life process?
Ans: Reproduction is essential for continuation of the species from generation to generation.
3. What are the different modes of unisexual reproduction?
Ans: modes of reproduction evolve only one parent is called unisexual reproduction.
(a) Fission: The mode of reproduction in which unicellular organism split into two equal halves and produce new ones is called binary fission. For example amoeba and bacteria
(b) Fragmentation: The mode of reproduction in which body of plant breaks up into smaller fragments and each fragment grows into a new individual is known as Fragmentation e.g. Spirogyra , algae
(c) Budding: The mode of reproduction in which small buds when develop get separated and mature into new organisms is called Budding. E.g. Yeast, Hydra, Bryophyllum
(d) Spore formation: The mode of reproduction takes place by means of spores is called spore formation.eg. algae and fungi
The spores are covered by thick walls that protect them until they come into contact with another moist surface and can begin to grow.
4. Mention some of the spores of asexual reproduction.
Ans: Aplanospores, Zoospores, Akinetes and Conidia
5. What do you mean by vegetative propagation?
Ans: Vegetative propagation is the ability of plants to reproduce by using vegetative parts like root ,stem and leaves is called vegetative propagation.
6. Why there are so many methods of reproduction?
Ans: It is due to complexity of the body design of organisms.
7.What is sexual reproduction?
Ans: Sexual reproduction is the process in which two components ( male and female) are involved to produce offspring of their own kind.
8. Name the reproductive organ of a flowering plant
Ans: The flower is a reproductive organ of a flowering plant
9. Name the male and female part of flower.
Androecium is the male part of a flower,and Gynoecium is the female part.
Androecium is a group of stamens. Each Stamen consists of a stalk called the filament and a small bag like structure called the anther at the tip. The pollen grains are contained in the anther within the pollen sacs
Gynoceium is the female part of the flower and consistsof the carpels or ovary.
Gynoceium has three parts
1) Stigma
2) Style and
3) Ovary.
The ovary contains the ovules and each ovule carries within it an embryo sac, within which lies the egg cell or the female gamete.
10.How does sexual reproduction take place in flowering plants?
Ans: The sexual reproduction in flowering plants involves
1. Pollination 2. Fertilization
Transfer of pollen grains from the anther to the stigma is called pollination.
Pollen grains are transferred mainly by wind, water and insects. They are called as pollinating agents.
The fusion of a male gamete with egg is known as fertilization. The fertilized egg is known as zygote which develops into embryo.
11.Why are there so many varieties of fruits?
Fruits develop by many ways so there are many varieties of fruits. For example, some fruits develop without the act of fertilization. Such fruits are called arthenocarpic fruits. E.g. seedless grapes, guava, mango etc.
12.Explain different parts of flower?
Ans: Following are the parts of flowers:
a)Sepal: Green leafy part of flower that protect flower in bud condition.
b) Petal: Coloured leafy part of flower that attract insect for pollination
c) Stamen: The male parts of flower that contain pollen grain
d)pistil: The female parts of flower that contain ovary at bottom
what are the various methods of vegetative propagation?
13.Explain three artificial methods of Vegetative Propagation
Ans: Cutting: Here the cuttings of the "parent" plant are removed and placed in a suitable environment so that they can grow into a whole new plant. For example rose cutting.
Layering: The stem is bent down and the target region buried in the soil. The buried part of stem develops roots and is detached from the plant and develops into new plant.
Grafting: In grafting a shoot or bud of a selected, desired plant (scion) is grafted onto the stock of another type of plant.
Plant tissue culture: Tissue culture is the artificial method of reproduction where a small cutting of plant such as root or stem is taken and is grown in laboratory condition by providing it with suitable nutrients in a media and growing them in a petri plate or test tubes. The plant is provided with the most hygienic condition.
★ What is reproduction ?
All living organism have a lifespan after which they die no organism live forever how we were all living organisms are able to produce more of their own kind before they die . This ability to reproduce is a common characteristics of all the living organism , the process by which living organism can produce more of their own kind is known as reproduction.
★ what are the vegetative parts of the plant ?
The vegetative parts of plants are as follows :-----
- Roots
- Stem
- Leaves
★ Which part of the plant is known as reproductive parts of the plant ?
Flower is known as reproductive part of the plant .
★ List the types of reproduction .
The methods of reproduction in plants are generally grouped into two main types 'Asexual' and 'Sexual' reproduction.
★ Asexual Reproduction :----- in a sexual reproduction and individual can reproduce on its own without involvement of any other individuals of the same species the division of the bacterial cell into daughter cell is an example of asexual reproduction. Asexual Reproduction is not however limited to single celled organism most of the plants have the ability to reproduce asexually.
★ Sexual Reproduction :------ Sexual reproduction requires the involvement of two individual typically one of each sex. Normal human reproduce is a common example of sexual reproduction in flowering plants the reproductive parts are located in the flower.
( NOTE :----- As you are able to watch in the given attachment )
★ what are seed dispersal ?
most higher plants reproduce by producing seeds the seeds are also help in plants to spread out and grow in new places sometimes a long distance away from the parent plant this is important because if the seeds are not disperse a large number of germinating seedlings can grow a very closer to Parent plant this will result in competition between all such seedlings as well as parent plant in the competition for getting light ,space, water and nutrition ; all of these are important for plants to be able to grow and survive seed can be disposed in a number of different ways depending on the nature of the see that they may be carried by wind , they may be carried out by water or animals or by the explosion of the fruits.
★ Types of seed dispersal method .
★ Dispersal by wind -----»
Seeds are very light get carried out to be a new place by wind the seeds of the acids are almost as fine as dust many others like the seed of aak (madar) han hair Regrowth which act like little parachutes and carried the seeds away from the parent plant .
★ Dispersal by water -----»
Fruits which floats such as those of the lotus flower Lily and the coconut Palm are carried away by water coconuts can travel for the thousands across seas and ocean.
★ Dispersal by animals ------»
Some plants have juicy fruit that animal like to eat the animal eat the fruit but only the juicy part is digested the seeds passthrough the animal digestive system as such they are deposited on the land Where are they formed new plants this land can be far away from the parent plant tree and Apple seeds are dispersed in this way only Birds also like to eat some fruits they helped to disperse the seeds to another area for they are dropping some seeds of those of urnea how spinny seeds with hooks these seats get attached to the for of animal and are carried away .
★ Dispersal by explosion of the fruit -----»
Some plants have pods that explode when ripe and shoot out to the seeds , The seeds can get scattered far away from the parent plant. seeds of Pea and Bean plants are formed in pods.The pod is dried thus the pod brusts open and their seeds get scattered.
