3rd Class Science Parts of Plants Plants Leaves

     Plant's Leaves

Part of plant where food is manufactured is called leaf of the plant. It is green in colour, because of the presence of a green pigment, called chlorophyll. Chlorophyll absorbs sunlight, and with the help of carbon dioxide and water makes food for the plant.

Carbon dioxide+\[Water\frac{Cholorphyll}{Sunlight}\] Glucose + Oxygen

This process is called photosynthesis.

Plants also carry out respiration process in which food formed in leaf is oxidized in the presence of oxygen to give energy. Carbon dioxide and water is also released in this process.

Glucose + oxygen ---> Energy + Carbon dioxide + water

Release and intake of oxygen and carbon dioxide occurs through small opening in the leaves called stomata.

Look at the following:

Water loss from the plants also occurs through the stomata present on leaves, called transpiration. In some desert plants, like cactus, photosynthesis process is performed by stem as leaves in these plants are reduced to spines. Veins present on the leaves carry water and minerals from the soil to the leaf and also the food prepared in the leaves is carried to different parts of the plant. Venus fly trap, Bladderwort, pitcher plant etc. are carnivorous that trap insects and other animals.

Look at the following picture of bladderwort (A carnivorous plant):

There are some non green plants also called fungi, like mushrooms and moulds. They don't have chlorophyll and hence can't prepare food. They obtain their food from dead and decayed plants.     Look at the following picture of mushroom plant:

      Consider the following statements:

Statement 1: All plants are green.

Statement 2: All green plants prepare its own food.

Which one of the following is correct about the above statements?

(a) Statement 1 is true and 2 is false

(b) Statement 2 is true and 1 is false

(c) Both statements 1 and 2 are false  

(d) Both statements 1 and 2 are true

(e) None of these

Answer: (b)

Explanation

There are non-green plants also like mushroom that doesn't undergo the process of photosynthesis and depends on dead decayed parts of plants for its food. All green plants prepare their food. Therefore, option (b) is correct and rest of the options is incorrect.