Definitions [2]
Definition: Abiogenesis
Abiogenesis is the concept that living organisms can arise naturally from non-living substances.
Definition: Autogenesis
Autogenesis is another term for spontaneous generation, meaning self-origin of life from non-living matter.
Key Points
Key Points: Origin of Life on Earth
- The Big Bang Theory states that the universe originated about 13.8 billion years ago.
- Earth was formed about 4.5 billion years ago from a hot, molten mass.
- Early Earth had no atmosphere and was covered with gases like water vapour, CH₄, CO₂, and NH₃.
- As Earth cooled, water vapour condensed to form oceans.
- The ozone layer formed later, helping to protect life on Earth.
