Getting to Know Plants
Correct the following statements and rewrite them in your notebook :
(a) Stem absorbs water and minerals from the soil.
Roots absorbs water and minerals from the soil.
(b) Leaves hold the plant upright.
Stem holds the plant upright.
(c) Roots conduct water to the leaves.
Stem conducts water to the leaves.
(d) The number of petals and sepals in a flower is always equal.
Statement is not correct
(e) If the sepals of a flower are joined together its petals are also joined.
Statement is correct.
(f) If the petals of a flower are joined together, then the pistil is joined to the petal.
Statement is correct.
Draw (a) a leaf, (b) a taproot and (c) a flower you have studied for table 7.3 ?
Can you find a plant in your house or in your neighbourhood, which has a long but a weak stem? Write its name. In which category would you classify it ?
Yes, money plant. It belongs to creepers.
What is the function of a stem in plant ?
Functions of a stem in plant are :
(1) The stem bears the weight of the plant and keeps the plant erect. It supports the branches and leaves in such a way that the leaves are properly exposed to sunlight and air to carry out photosynthesis and respiration efficiently. The stem also supports flower and fruits.
(2) The water and minerals absorbed by the roots are conducted upwards by the stem to the branches, leaves etc.
(3) It also conducts the prepared food (starch) downwards from the leaves to all other parts of the plant.
(4) Green stems manufacture food for the plant by photosynthesis
Which of the following leaves have reticulate venation ?
wheat, tulsi, maize, grass, coriander (dhania) China rose.
Leaves having reticulate venation are Tulsi, Coriander (dhania), China rose.
If a plant has fibrous root, what type of venation do its leaves likely to have ?
The venation of the leaf is parallel for plants having fibrous root.
If a plant has leaves with reticulate venation, what kind of roots will it have ?
If a plant has leaves with reticulate venation than it will have tap roots.
Is it possible for you to recognize the leaves without seeing them ?
Yes, it is possible to recognize the leaves without seeing them by touching or smelling.
Write the names of the parts of a flower ?
Sepals, petals, stamen, pistil.
Which of the following plants have you seen ? Of those that you have seen, which one have flowers ?
Grass, maize, wheat, chilli, tomato, tulsi, peepal, shisham, banyan, mango, jamun, guava, pomegranate, papaya, banana, lemon, sugarcane, potato, groundnut.
|Plants having flowers||Plants not having flowers|
Name the part of the plant which produces its food, Name this process ?
Leaves of the plant produces food by the process of photosynthesis.
In which part of a flower you are likely to find the ovary?
Name two flowers each with joined and separated sepals ?
Flowers with joined sepals are in rose, lady fingers, brinjal.
Flower with separate sepals in mustard and dhatura.
InText Questions and Answers
Enclose a branch of a potted plant in a polythene bag and tie up its mouth as shown in Fig. 7.1. After some time observe the inner surface of the bag.
What do you see ?
We see drops of water inside the polythene bag.
How did water droplets appear in the bag ?
Water droplets come from the plants.
Where could they have come from ?
They could have come from the leaves.
Why do we tie a bag around the leaves ?
We tied a bag around the leaves to test if water comes out of the leaves or not.
Place the leaf in the beaker and pour enough alcohol to cover it. Boil on a low flame till the green colour comes out.
Take out the leaf and wash it in water. Put it in a petri-dish/plate and pour some iodine solution over it.
What did you observe ?
We observe that leaf becomes blue-black.
Did you make a similar observation in the chapter 1, food we eat ?
Does it mean leaf has food/carbohydrate in it ?
Yes, leaf has carbohydrate in it.
Uproot two weed plants from the roadside. Cut away the root of one. Place both in the soil in the pots as shown in Fig. 7.16. Water the pots daily. Observe both plants for four days.
In your class how many of the plants with their roots intact withered as compared to those that had no roots?
All plants having no roots withered whereas plants having roots did not wither.
On the basis of the experiment can you say that plants generally wither without their roots ?
Yes, we can say that, plants generally wither without their roots.
Based on this experiment tell why the root is inside the soil.
The root absorbs water from the soil.
Place the seeds on wet cotton in a bowl. Keep the cotton moist by adding a little water every day. After about five days try and separate the small seedlings from the cotton. Was it easy to do this ? Did the roots become free of cotton ?
- No, it was not easy to separate the small seedlings from the cotton.
- No, the roots do not become free of cotton.