List three examples of reproduction in plants through underground roots? Answer
Sweet potato, Dahlia, Asparagus
Explain how layering is different from grafting in the artificial method of reproduction in plants? Answer
The pollen grains of a flower are hairy and light. Will it be close to the mother plant after dispersal? Answer
What will happen if the pollen of Hibiscus flower reaches the stigma of a rose flower? Answer
Vegetative propagation by roots.
Do you think insect pollinated flowers can also be pollinated by wind? Give reasons? Answer
Vegetative propagation by stem.
How is a rose plant propagated? Answer
Rose plants can be propagated through cutting from its stem.
On which part of the pistil do the pollen grains settle during the pollination? Answer
Spirogyra multiplies through fragmentation.
Spirogyra is a common freshwater alga. It grows as fine strands. When conditions are ideal and enough nutrients are available in the water, the alga breaks into fragments on its own. Each fragment grows into a new organism.
Which part of a plant develops into a fruit? Answer
Fertilization does not take place because the stigma of rose flower recognizes the Pollen of Hibiscus flower as a foreign organism. So no Pollen tube germinate.
Explain how spirogyra multiplies? Answer
Yes, because there are various means of pollination. It depends on the size, shape and some other characters of the flower.
(a)Tissue culture is an artificial method of vegetative propagation which is undertaken in specialise laboratories.
(b)It is based on the principle that a new plant can be grown from a single cell.
(c)A piece of stem, leaf or root tissue is placed under specific conditions in a semi solid solution containing nutrients and plant hormones in a closed container.
(d)Roots and shoots then develop from this mass of cells and form new platelets.
Describe the embryo of a seed? Answer
(a)The fertilized egg begins to divide inside the ovule and develops into an embryo.
(b)The embryo has a radical and plumule. It is attached to one or two cotyledons.
(c)Upon germination the radicle will develop into the root system, while the plumule will develop into a shoot system.
Differentiate between unisexual and bisexual flowers? Answer
Flowers which contain either the male or female reproductive parts are called unisexual flower. For eg; Watermelon, papaya, While the flower which contain both male (stamen) and female (pistil) reproductive parts are called bisexual flower. For eg; lily, hibiscus etc.
When fully formed dry seeds get favourable conditions, the germinate. Seeds that have a thin seed coat germinate, in 2 to 3 days. If the seed coat is very hard, the seed takes many days to germinate. When a seed germinates, a new plant is formed.
A farmer wants to grow strawberries, bananas and grapes on his farm. Which method of propagation will he employ to do so?
Rajni wants to propagate Jasmines, Roses dahlias, lilies and chrysanthemums in her garden. Which part of these plants will she have to use to propagate them?
Explain how layering is different from grafting in the artificial method of reproduction in plants?
(a)In layering, a part of a branch of the plant is bent down and covered with soil. The remaining part of the branch remains above the ground.Once the roots start developing, new shoots will start to grow from the ground. The branch can then be cut from the parent plant. While in grafting two plants of the same species are involved. The cut part of the stem is called the scion and the second part to which the scion is attached is called the stock. The grafted areas are then covered with a layer of soil and compost. Soon, the stock and scion join together to form one plant.
(b)Layering is often done in plants like Jasmine which have long and Slender branches, while plants having a thick woody stem can be easily used for grafting.
link to this page by copying the following text Also Read