Friction — Science STD 8 — Question

What is the role of microorganisms in the production of biogas?

Name one compound which is decomposed into hydrogen and oxygen by using the chemical effect of electric current.

State whether human beings reproduce by sexual method of asexual method.

Which cells in the human body can contract (and relax)?

Write True and False against the following statements and also correct the false statement. A physical process in which a substance reacts with oxygen to give off heat is called combustion.

Name two non-metals which are used in fireworks (crackers, etc.)

Name the process in yeast that converts sugars into alcohol.

Fill in the following blanks with suitable words: The process of ______________ ensure continuity of life on earth.

Write two important uses of coke.

Variety of all forms of life found in a region' is known by a specific name, what is it ?