NCERT Solutions for Class 7th Science
Chapter 1 - NUTRITION IN PLANTS
(Complete Downloadable Chapter Solution PDF file is at the bottom of the page)
Q.1 Why do organisms need to take food?
Ans Organisms need food:
1) to survive.
2) to get energy for doing various activities like walking, studying etc.
3) for growth and maintenance of the body.
Q.2 Distinguish between a parasite and a saprotroph.
Q.3 How would you test the presence of starch in leaves?
Ans The presence of starch can be determined by iodine test. Take two potted plants of the same kind. Keep one in the dark (or in a black box) for 72 hours and the other in the sunlight. Now, take one leaf from each potted plant and put a few drops of iodine solution on them. The leaf of the plant which was kept in sunlight will show blue black colour indicating the presence of starch. The leaf of the plant which was kept in dark will not show blue black colour indicating the absence of starch.
Q.4 Give a brief description of the process of synthesis of food in green plants.
Q.5 Show with the help of a sketch that the plants are the ultimate source of food.
Q.6 Fill in the blanks:
(a) Green plants are called _________________ since they synthesise their own food.
(b) The food synthesised by the plants is stored as _________________.
(c) In photosynthesis solar energy is captured by the pigment called ___________.
(d) During photosynthesis plants take in ___________ and release ____________.
Q.7 Name the following:
(i) A parasitic plant with yellow, slender and tubular stem.
(ii) A plant that has both autotrophic and heterotrophic mode of nutrition.
(iii) The pores through which leaves exchange gases.
Q.8 Tick the correct answer:
(a) Amarbel is an example of:
(i) autotroph (ii) parasite (iii) saprotroph (iv) host
Q.9 Match the items given in Column I with those in Column II:
Column I Column II
Chlorophyll Bacteria
Nitrogen Heterotrophs
Amarbel Pitcher plant
Animals Leaf
Insects Parasite
Q.10 Mark ‘T’ if the statement is true and ‘F’ if it is false:
(i) Carbon dioxide is released during photosynthesis. (T/F)
(ii) Plants which synthesise their food themselves are called saprotrophs. (T/F)
(iii) The product of photosynthesis is not a protein. (T/F)
(iv) Solar energy is converted into chemical energy during photosynthesis. (T/F)
Ans (i) Carbon dioxide is released during photosynthesis. (F)
(ii) Plants which synthesise their food themselves are called saprotrophs. (F)
Q.11 Choose the correct option from the following:
Which part of the plant takes in carbon dioxide from the air for photosynthesis?
(i) Root hair (ii) Stomata (iii) Leaf veins (iv) Sepals
Q.12 Choose the correct option from the following:
Plants take carbon dioxide from the atmosphere mainly through their:
(i) roots (ii) stem (iii) flowers (iv) leaves