Why is water essential for life?
Water is essential for life because
(i) all life processes that take place in the cells require water medium.
(ii) water is needed for transportation of substances from one part of the body to the other in a dissolved form.
(iii) All the reactions in the body or within the cells occur between substances that are dissolved in water.
Why is the atmosphere essential for life?
How are living organisms dependent on the soil? Are organisms that live in water totally independent of soil as a resource?
You have seen weather reports on television and in newspapers. How do you think we are able to predict the weather?
What are the two forms of oxygen found in the atmosphere?
