| 1. | They could separate combinations of molecules from the surroundings |
| 2. | They were able to reproduce |
| 3. | They were partially isolated from the surroundings |
| 4. | They could maintain an internal environment |
The concept of chemical evolution is based on:
| 1. | crystallization of chemicals |
| 2. | interaction of water, air, and clay under intense heat |
| 3. | effect of solar radiation on chemicals |
| 4. | possible origin of life by a combination of chemicals under suitable environmental conditions |