Evolution Question 100

100. Which was absent in the atmosphere at the time of origin of life?

(a) $NH_3$

(c) $O_2$

(b) $H_2$

(d) $CH_4$

Show Answer

Answer : c

Hints & Solution

(c) Oxygen gas was not present due to reducing atmosphere, it only came to existence after the evolution of photosynthesis process.