The Stanley Miller and Harold C. Urey performed an experiment by recreating in the laboratory, the probable atmosphere of the primitive earth

1.The Stanley Miller and Harold C. Urey performed an experiment by recreating in the laboratory, the probable atmosphere of the primitive earth.
(i) What was the purpose of the experiment?
(ii) In which form was the energy supplied for the chemical reactions to occur?
(ii) For how long was the experiment run continuously?
(iv)Which gases were used during the experiment to simulate the primitive atmosphere?

Ans: (i) The purpose of the Urey and Miller's experiment was to prove that life has originated spontaneously from non living matter i.e. to provide experimental evidence for the theory of abiogonesis or chemical evolution.
(ii) Energy was supplied in the form of electrical discharges from electrodes at 800°C.
(iii) The experiment was run continuously for a week.
(iv) The gases used during experiment to simulate the primitive atmosphere were methane, ammonia, hydrogen and water vapour.

2. Write the full form of SCID and mention the cause of this congenital disorder. Mention any one difference between SCID and AIDS

Ans: SCID is Severe Combined Immuno deficiency. It is a congenital disease caused due to absence of T and B-lymphocytes, two types of white cells necessary for fighting infections, since birth.
It differs from AlDS in the respect that in AIDS, T-helper cells which stimulate antibody production by B-cells are reduced, due to viral attack while in SCID, both T and B-cells are absent ie.,individuals are born without these cells