Question

Explain Oparin's theory related to the origin of life.

Hint:

Oparin's theory of chemical evolution influenced later experiments, such as the Miller-Urey experiment, which simulated early Earth conditions.

Answer 1

Step 1: Introduction to Oparin's Theory.
Oparin's theory of the origin of life, also known as the Chemical Evolution Theory, was proposed by Alexander Oparin in 1924. According to Oparin, life originated from simple organic molecules through chemical reactions in the early Earth environment.
Step 2: Stages of Life's Origin According to Oparin.
1. Prebiotic Chemistry: Oparin proposed that in the primitive atmosphere, there were no free oxygen molecules, and the atmosphere consisted mainly of methane (CH₄), ammonia (NH₃), hydrogen (H₂), and water vapor (H₂O). In such an environment, simple molecules like methane and ammonia could react under the influence of energy sources (like lightning or UV radiation) to form organic molecules. 2. Formation of Colloidal Systems: Oparin suggested that, over time, these organic molecules formed more complex substances, such as amino acids and proteins. These complex molecules formed colloidal systems, which were precursors to cells. 3. Coacervates: He proposed that these molecules aggregated into "coacervates," or droplets, which were the first primitive forms of life. Coacervates could maintain internal conditions separate from their environment, much like cells do today. 4. Evolution to Protoplasm: Over time, these coacervates could have developed the ability to replicate and metabolize, leading to the formation of simple life forms.
Step 3: Conclusion.
Oparin's theory laid the foundation for understanding how life might have arisen from non-living matter through gradual chemical processes.
Final Answer: \[ \boxed{\text{Oparin's theory suggests that life originated from simple organic molecules through chemical reactions.}} \]