Download Plant life

Plant life
Knowledge and understanding:1. Vegetative propagation: Reproduction of plants from their body parts other than seeds is called
vegetative propagation.
2. Germination: The process of changing a seed into seedlings.
3. Dispersal of seeds: The process of scattering or spreading of seeds to different places is called
dispersal of seeds.
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Seeds are dispersed by wind have wings on them.
You can see a very small baby plant between the seed leaves.
Fungicides are used to kill microbes.
Paddy grows well in a wet and clayey soil
Carrot is a vegetable.
Name of an oil producing crop peanut .
The agent of dispersal for cotton seed is wind.
Seeds of this plant are dispersed by the method of explosion balsam.
Some plants grow with the help of tiny structures called spores.
Coconut floats in water and is carried away to far off places.
Complete the table: reproduction in plants
New plants from
seeds
mango
pea
cotton
New plants from
stem
Rose
Sugar cane
Money plant
New plants from
roots
Carrot
radish
turnip
New plants from
spores
mushrooms
ferns
New plants from
leaves
bryophyllum
begonia
Seed dispersal
Dispersal by wind
Dispersal by water
Dispersal by explosion
Dispersal by animals
cotton
madar
hiptage
lotus
coconut
Water lily
Pea seed
balsam
caster
xanthium
Spear grass
Answer the following
1. In what ways are plants useful to us?
Ans. Plants provide us food, oxygen , building materials, fibers for clothing, medicines and many other
things. Plants also help in maintaining balance between oxygen and carbon dioxide in the
environment. Roots of trees bind the soil, thus preventing soil erosion.
2. Explain the parts of a seed.
Ans. A seed contains the embryo or baby plant that grows into a plant. It is covered by a seed coat
for protection. Seed also contains seed leaves or cotyledons which provide food for the baby plant.
3. Why are not all the seeds produced by a plant able to grow into new plant?
Ans. All the seeds produced by a plant are not able to grow into new plants as many seeds are
destroyed by insects ,animals and bad weather conditions.
4. What will happen if all the seeds produced by a plant were to fall down below it and start
growing?
Ans. All seeds do not grow into new plants. Some seeds do not find suitable conditions of air, water,
and warmth and so fail to give rise to new plants.
5. Define seed dispersal. Why is it essential?
Ans. The process of scattering or spreading of seeds to different places is called dispersal of seeds. If
all seeds fall under the parent plant, they would grow in very crowded conditions. They would have
to fight against each other for space, water, minerals, and light. Only stronger ones would live.
6. Explain the stages in germination.
Ans. The seed absorb water and the cells of the embryo start dividing. This results in the growth of
the baby plant inside the seed. As the baby plant grows radical and plumule emerges from the seed
breaking the seed coat .The radical forms the root and the plumule forms the shoot with stems and
leaves.
7. Distinguish between rabi and kharif crops.
Ans. Crops like rice, maize, cotton, etc. are grown in summer and harvested at the end of the
monsoons are called kharif crops.
Crops like wheat ,grain, mustard, that are grown in winters and harvested in summer season are
called rabi crops.
8. Why do farmers add manure or fertilizers to the soil in which crops are grown?
Ans. Farmers add manure and fertilizers to make the soil fertile. Manure is made from dried leaves
and cow dung. Chemical fertilizers are made in factories. Super phosphate and ammonium sulphate
are examples of fertilizers.