From Protocells to Species: Understanding Chemical and Biological Evolution

Biomolecules Were Created

(Simple organic molecules) - Biomolecules were synthesized when the components of Earth's primitive atmosphere reacted on contact with each other.

More and More Complex Biomolecules Were Created

From the simple molecules in the "primordial soup."

Protocells Were Formed

When the biomolecules became organized in spherical membranes, with proteins and nucleic acids inside them.

Primitive Cells

(Similar to prokaryotic cells) were formed when some protocells managed to exchange matter and energy with their surroundings and produce replicas of themselves.

Different Types of Prokaryotic Cells

Were created from primitive cells: heterotrophic, photosynthetic, and aerobic cells.

The First Eukaryotic Cells Appeared

As a result of endosymbiosis. The endosymbiotic theory suggests a prokaryotic cell folded its membrane to increase the surface area, this folding created the nucleus.

Fixist theories uphold the idea that the species that currently exist on Earth were created by God and they have not changed in any way.

Cuvier's Catastrophism

Cuvier proposed the theory of catastrophism - Earth has experienced many catastrophes in its history and this had led to the disappearance of many species. They were never believed to be pre-existing forms of current species.

Actualism

Events of the Earth's distant past were caused by the action of forces that are identical to those that are in operation today, and that changes in nature take place slowly, gradually, and continually.

Evolutionism

Maintains that species undergo a process of transformation which results in the appearance of new species.

Natural selection is a process that favors the individuals in populations that are best adapted to the environment and which, over time, will lead to the appearance of new species.