NCERT Solutions for Class 7 Science Chapter 9 Soil in English Medium or in Hindi Medium free PDF file download or View online without downloading for academic session 2022-2023 based on latest NCERT Books. All the NCERT Solutions 2022-2023 are also given in Video Format also based on latest NCERT Books 2022-23. NCERT Solutions Offline Apps for new academic session 2020 – 21 are also free to download. Visit to Discussion Forum to Share Your View with your friends.
NCERT Solutions for Class 7 Science Chapter 9
Class 7 Science Chapter 9 Answers
CBSE NCERT Solutions for Class 7 Science Chapter 9 Soil are given below to use online or download in PDF free to use. Solutions are in English Medium as well as Hindi Medium format. Download NCERT Solutions Apps 2022-23 of Class 7 all subjects for Offline use.
Class 7 Science Chapter 9 Solutions and Explanation in Videos
Important Questions on 7th Science Chapter 9 for Practice
1. Soil conservation measures are mainly aimed at protecting which of the following?
(b) Top soil
(c) Sub soil
(d) Soil organisms
2. The microorganisms present in the soil require moisture (water) and nutrients for growth and survival. Choose from the options below the habitat (place) where the soil has plenty of water and nutrients.
(c) Open field
(d) Cricket ground
3. Read the following statements with reference to soil.
(i) Weathering is a very fast process of soil formation.
(ii) Percolation of water is faster in sandy soils.
(iii) Loamy soil contains only sand and clay.
(iv) Top soil contains the maximum amount of humus.
Choose the correct statements from the above.
(a) (ii) and (iv)
(b) (i) and (iii)
(c) (ii) and (iii)
(d) (i) and (ii)
4. Availability of water and minerals in the soil for maximum absorption by roots is in the–
(d) surface of soil
5. Read the following statements and give the appropriate terms for each of them.
(a) The process of breakdown of rocks by the action of wind, water, sunlight.
(b) Removal of top soil during heavy rains or strong winds.
(c) Accumulation of wastes in the soil generated by human activity which alter the features of soil.
(d) The process of movement of water into deeper layers of soil.
6. Which of the following situations – ‘A’ or ‘B’ – is advantageous for absorption of water and minerals? Why?
Situation ‘A’: Growth and branching of roots in the C-horizon.
Situation ‘B’: Growth and branching of roots in A and B horizons.
7. A man digging a pit found that he could dig with ease initially but digging became difficult as he went deeper. He could not dig beyond a depth of 5 feet. Provide a suitable scientific explanation.
Answers of Important Questions
5. (a) Weathering (b) Erosion (c) Soil pollution (d) Percolation
6. Situation ‘B’ is advantageous to plants because A- and B- horizons are rich in water, minerals and humus.
7. The soil surface has loose top soil which is easier to dig. At deeper layers, partially weathered rocks or bedrocks are present, which are hard making digging difficult.
Important NCERT Questions Class 7 Science Chapter 9
How is clayey soil useful for crops?
Clayey soil is rich in humus and are very fertile, so it is suitable for growing cereals like wheat and gram. Such soil is good at retaining water. For paddy, soils rich in clay and organic matter and having a good capacity to retain water are ideal. For lentils (masoor) and other pulses, loamy soils, which drain water easily, are required.
Describe the cross section of soil and its various layers.
A vertical section through different layers of the soil is called the soil profile. Each layer differs in feel (texture), colour, depth and chemical composition. These layers are referred to as horizons. The uppermost horizon is generally dark in colour as it is rich in humus and minerals. The humus makes the soil fertile and provides nutrients to growing plants. This layer is generally soft, porous and can retain more water. It is called the topsoil or the A-horizon. The next layer has a lesser amount of humus but more of minerals. This layer is generally harder and more compact and is called the B-horizon or the middle layer. The third layer is the C-horizon, which is made up of small lumps of rocks with cracks and crevices. Below this layer is the bedrock, which is hard and difficult to dig with a spade.