P6 Science Revision-Man and His Environment

Q1. When does deforestation occur n what is a recommended remedy to this problem? (3m)
Ans: Deforestation occurs when forests are cleared and trees are cut down to clear land for the construction of buildings and to retrieve raw materials for construction, furniture making and paper production. 
A recommended remedy is reforestation.

Q2. Explain a positive n a negative impact of science and technology on our lives. (4m)
Ans: Science and technology has helped to produce fermented food and canned food. As such, a greater variety of food is produced and these foods have a longer shelf life. Thus, the positive impact is that food is more readily available.
Science and technology has also introduced more forms of vehicles which inevitably produce harmful substances that pollute the air. Hence, the negative impact is air pollution. 

Q3. How is Genetic Modification (GM) useful?
List 3 different ways. (3m)

Ans: GM enables farmers to produce crops that are pest-resistant or drought-resistant, thus leading to a greater yield for the farmers. 
With pest-resistant crops, less pesticides is needed and this results in cost savings for the farmers and less pollution to the environment.
The quality of food is improved by changing flavour and having higher vitamin content.