To determine the correct sequence of steps in the origin of life according to modern theory, we can break down the process as follows:
### Step-by-Step Solution:
1. **Free Atoms (A)**: The origin of life begins with the presence of free atoms, which are the basic building blocks of matter. These atoms include elements like carbon, hydrogen, oxygen, and nitrogen.
2. **Origin of Simple Inorganic Compounds (D)**: The next step involves the formation of simple inorganic compounds. These compounds are formed when free atoms combine in various ways, leading to molecules like water (H2O), carbon dioxide (CO2), and ammonia (NH3).
3. **Origin of Simple Organic Compounds (B)**: Following the formation of simple inorganic compounds, simple organic compounds are formed. This includes basic organic molecules such as amino acids, fatty acids, and simple sugars.
4. **Origin of Complex Organic Compounds (E)**: The next step is the formation of complex organic compounds. These compounds are larger and more complex molecules, including proteins, nucleic acids, and polysaccharides.
5. **Origin of Prebiotic Molecules (C)**: After the formation of complex organic compounds, molecular aggregates or prebiotic molecules are formed. These aggregates are essential for the development of life and include structures like coacervates and proteinoid microspheres.
6. **Prokaryotes (F)**: The final step in this sequence is the emergence of prokaryotic cells, which are the simplest forms of life. These cells represent the first living organisms and mark the transition from non-living chemical systems to living biological systems.
### Correct Sequence:
The correct sequence starting from the oldest to the latest is:
- A (Free Atoms)
- D (Origin of Simple Inorganic Compounds)
- B (Origin of Simple Organic Compounds)
- E (Origin of Complex Organic Compounds)
- C (Origin of Prebiotic Molecules)
- F (Prokaryotes)
### Final Answer:
The correct sequence is: **A, D, B, E, C, F**.
---
