CBSE NCERT Solutions for Class 7 Science Chapter 1

NCERT class 7 science solutions science help in instant doubt clearance and provide a strong basic foundation for the students. The topics are well explained. If the student is unable to comprehend the lessons,they can seek help from his or her peers or teachers.

CBSE NCERT Solutions for Class 7 Science Chapter 1:

Question-1:

How would you test the presence of starch in leaves?

Solution:

Steps to test the presence of starch in leaves:
Step 1: A fresh leaf is taken.
Step 2: The leaf is boiled in alcohol for few minutes to remove chlorophyll.
Step 3: Now, dip this leaf in iodine solution.
Step 4: The color of the leaf will changes into blue black color when iodine is
added to it which shows the presence of starch in it.

Question-2:

Give a brief description of the process of synthesis of food in green plants.

Solution:

Photosynthesis is the process of synthesis of food in the plants with the help of
chlorophyll and carbon dioxide in the presence of sunlight.
Water and minerals present in the soil are absorbed by the roots and transported to the leaves through xylem.
Carbon dioxide from air is taken through stomata present in leaves.
Leaves are the food factories of the plants which capture the energy of the sunlight with the help of chlorophyll. This energy is used to synthesize food from carbon dioxide and water.
Sunlight
Carbon dioxide + Water --------------------> Carbohydrate + Oxygen
Chlorophyll

Question-3:

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.

Solution:

(i) Cuscuta (Amarbel) (ii) Pitcher plant (iii) Stomata

Question-4:

Tick the correct Solution: Amarbel is an example of:
Option A: autotroph
Option B: parasite
Option C: saprotroph
Option D: host

Solution:

Correct Option: B- Amarbel is a parasite.