Origin of earth dates back to
$10,000-15,000$ million years ago
$4000-4600$ million years ago
$500-1000$ million years ago
$2000-3000$ million years ago
$A$ : During evolution the early time period was without ozone layer.
$R$ : Ozone layer absorbs $U.V.$ rays to some extent.
After about how many years of formation of earth, life appeared on this planet?
State the theory of abiogenesis. How does Miller’s experiment support this theory ?
Describe various theories of origin of life.