Class 7 Science Chapter 16 MCQ

Here, all the statements are correct. Hence your answer will be option [D].

Most of the water present on earth is not fit for consumption by us. Sea and oceans contain salty water which cannot be drunk. Even most of the fresh water is frozen as ice in glaciers and polar regions. Hence, we are left with limited amount of water from lake, river and under the ground.

Here, all the statements are correct. Hence your answer will be option [D].

Snow and ice are frozen while water vapor is in gaseous state. Water from lake and river are in liquid state.

Here, all the statements are correct. Hence your answer will be option [D].

Here, all the statements are correct. Hence your answer will be option [D].

Among the given options, drip irrigation is a way to use water economically because the installation of drip irrigation techniques requires less amount of water.

Here, all the statements are correct for the causes for the shortage of water are.

Here, all the statements are correct. Hence your answer will be option [D].

Here, all the statements are correct. Hence your answer will be option [D].

Here, all the statements are correct. Hence your answer will be option [D].

Water cycle does not involve rainwater harvesting. Rainwater harvesting involves recharging the groundwater.

The process of seeping of water into the ground is called “infiltration”.

Rain is the source of water on earth. And about 71% of the earth’s surface is covered with water. Though, heavy rainfall is the source of water, not for water shortage.

Snow is also solid form of water. Water is present in liquid form in ocean, river, lakes, ponds and under the ground. Water is present in gas form as water vapor in the air or atmosphere around us. Water is present in solid form on snow covered mountains, glaciers and as ice caps on the poles of the earth.

The main source of groundwater is the rain. The impermeable rock does not allow water to pass through it. So, water starts collecting above the impermeable rock and fills the soil and permeable rocks completely with water up to the level known as water table. The underground layer of soil and permeable rocks in which water collects under the ground is called an aquifer.

Plants need water to obtain nutrients from the soil, and to make food by the process of photosynthesis. The scarcity of water will affect the nutrient uptake by the plants and the process of food making photosynthesis in plants. The plants will not be able to make sufficient food for themselves and for animals. Remember, plants help in bringing rain by releasing a lot of water vapor into the atmosphere through transpiration. Scarcity of water for plants will reduce transpiration also.

Rain is the ultimate source of fresh water. In very cold regions, water drops in the sky freeze to forms snow leading to snowfall. Snow is the solid form of water. The water which falls from clouds as rain or snow is called precipitation.

If there are less number of trees and plants in the forest, less rain water will seep into the ground. Lesser number of trees and plants in the forest will bring less rainfall. Deforestation leads to less rainfall as well as laser seepage of rainwater into the ground. This depletes the water table.

In 1989, the village people of Bhujpur of Gujrat state along with a Non-Governmental Organization decided to harvest rainwater as there were shortage of water. For this purpose, 18 check dams were built on Rukmavati river and its many tributaries flowing through the area. The rainwater held by check dams seeped into the ground and recharge the groundwater in aquifers.

All the options are the responsible for water depletion, except snowfall. Snowfall, (rainfall etc.) is the form of water. And about 71% of the earth’s surface is covered with water. Though, increasing snowfall is the source of water, not for water shortage or depletion.

In ancient times, “Bawris” were mainly set up in cities and big towns for collecting water during drought periods, not “Big boros”.

Here, all the statements are correct. Hence your answer will be option [D].

Here, all the statements are correct. Hence your answer will be option [D].

The scarcity of water will affect the nutrient uptake by the plants and the process of food making (photosynthesis) in plants. So, due to scarcity of water, the plants will not be able to make sufficient food for themselves and for animals (including human beings). This will lead to severe shortage of food leading to famine.