NCERT Class 7 Science First Chapter Nutrition in Plants Exercise Solution

Exercise question and answer

(1) Why do organisms take food?

Ans:- All living organisms require food. Plants can make food for themselves but animals including humans cannot. They get it from plants or animals that eat plants.

(2) Distinguish between a parasite and saprotroph?

(3) How would you test the presence of starch in leaves?

Ans:- By the help of iodine test we can the presence  of starch in leaves.

(4) Give a brief description of the process of synthesis of food in green Plants?

Ans:- During photosynthesis, chlorophyll  containing cells of leaves in the presence of sunlight use carbon dioxide and  water to synthesise carbohydrate. The process can be represented in an equation.

Carbon dioxide + water sunlight carbohydrate oxygen.

(5) Show with the help of a spetch that plants are the ultimate source of food?

Ans:- Solar Energy – Tree – Herbivores

(6) Fill in the blanks:

(a) Green plants are called autotrophs since they synthesise their own food.

(b) The food synthesised by plants is stored as starch.

(c) In photosynthesis solar energy is absorbed by the pigment called chlorophyll.

(d) During photosynthesis plants take in carbon dioxide and release oxygen gas.

(7) Name the following:

(i) A parasitic plant with yellow, slender and branched stem.

Ans: Cuscuta

(ii) A plant that is partially autotrophic.

Ans: Insectivorous plant

(iii) The pores through which leaves exchange gases.

Ans: Stomata

(8) Tick the correct answer:

(a) Cuscuta is an example of:

Ans: Parasite

(b) The plant which traps and feeds on insects is:

Ans:Pitcher plant

(9) Match the items given in Column I with those in Column II:

Chlorophyll – Rhizobium.

Nitrogen – Heterotrophs.

Cascuta – Parasite.

Animals – Heterotrophs.

Insects – Pitcher plant.

(10) Mark ‘T’ if the statement is true and ‘F’ if it is false:

(i) Carbon dioxide is released during photosynthesis. = False

(ii) Plants which synthesise their food are called saprotrophs. = False

(iii) The product of photosynthesis is not a protein. = True

(iv) Solar energy is converted into chemical energy during photosynthesis. = True

(11) Choose the correct option from the following:

Which part of the plant takes in carbon dioxide from the air for photosynthesis?

Ans: Stomata

(12) Choose the correct option from the following:

Plants take carbon dioxide from the atmosphere mainly through their:

Ans: Leaves

(13) Why do farmers grow many fruits and vegetable crops inside large green houses? What are the advantages to the farmers?

Ans: As green house protects the plants to inside it from the climatic conditions outside and gives it suitable temperature for growth that’s why farmers do so.

Farmers get many advantages, they have bountiful crops and their crops are also protected from birds and animals.

Nutrition in Plants Inside Questions

(1) What is nutrient?

Ans:- Carbohydrates, Proteins, Fats, Vitamins and minerals are components of food. These components of food are called nutrients.

(2) What is called autotrophic?

Ans:- The mode of nutrition in which organisms make food themselves from simple substances is called autotrophic.

(3) What is called Heterotrophs?

Ans:- Animals and most other organisms take in food Prepared by plants they are called hetertrophs.

(4) What is cells?

Ans:- The bodies of living organisms are made of tiny units called cells.

(5) What is cell membrane?

Ans: – Cells can be seen only under the microscope. Some organisms made of only one cells. The cell is enclosed by a thin outer boundary called the cell membrane.

(6) Define cytoplasm?

Ans:- The nucleus is surrounded by a jell y like substance called cytoplasm.

(7) What is called stomata?

Ans:- Carbon dioxide from air is taken in through the tiny pores present on the surface of leanes. These Pores are surrounded by guard cells. Such Pores are called stomata.

(8) Define chlorophyll ?

Ans:- The leanes have a green Pigment called chlorophyll.

(9) What is Photosynthesis?

Ans:- Chlorophyll helps leanes to capture the energy of the sunlight. This energy is used to synthesis of food occurs in the Presence of sunlight. It is called Photosynthesis.

(10) What is called algae?

Ans:- Slimy, green Patches in Ponds or stagnant mater bodies. These are generally formed by the growth of organisms called algae.

(1) Name one example of plant which do not have Chlorophyll?

 Ans:- Cuscuta

(2) What is called insectivorous Plants? Give example?

 Ans:- Insect eating plants are called insectivorous plants.

 Example:– Pitcher Plant.

(3) What is called saprotrophie nutrition?

 Ans:- The mode of nutrition in which organisms take in nutrients from dead and decaging matter is called saprotrophic nutrition.

(4) What is called saprotrophs                          ?

 Ans:- Organisms with Saprotrophic mode of nutrition are called saprotrophic.

(5) What is called Symbiosis?

 Ans:- Some organisms line together and share both shelter and nutrients. This relationship is called symbiosis.