Combustion and flame — Science STD 8 — Question

Around which age menopause occurs in woman?

Explain why, water comes out more slowly from an upstairs tap than from a similar tap downstairs.

Name the microbe which causes malaria disease.

Large scale deforestation leads to the decrease in the amount of gas A in the atmosphere whereas the amount of gas B increases. The increased amount of gas B in the atmosphere causes an effect C which leads to excessive heating of the earth and its atmosphere producing an undesirable phenomenon D. What is A, B, C and D?

To which kind of synthetic fibres does terylene belong?

For what purpose is a hoe used?

Name the man-made fibre prepared from natural materials.

Name any two human diseases caused by protozoa.

Name the form of polyester which is replacing materials like glass and used for making bottles and jars.

Name two animals which reproduce sexually.