1. Endosymbiosis & Comparing Cells

2. Biomolecules Came First
Scientists knew that early earth had raw materials such as:
Water,
Hydrogen gas,
Nitrogen,
Ammonia,
Methane,
Carbon dioxide and Carbon monoxide

3. Miller and Urey’s Experiment
They filled a flask with hydrogen, methane, ammonia, and water to simulate the atmosphere, and they took great care to make sure there were no microorganisms that could contaminate the results. Then, they introduced an electric spark to simulate lightning.

4. Endosymbiosis
Symbiosis occurs when two different species benefit from living and working together.
When one organism actually lives inside the other it's called endosymbiosis.
Organism 1
Organism 2

5. Endosymbiotic Theory
The endosymbiotic theory states that eukaryotic cells arose from communities of prokaryotic cells.
Small prokaryotes began to live inside other cells.
Some prokaryotes could use oxygen to generate energy and these became mitochondria
Other prokaryotes were capable of photosynthesis and thus became the chloroplasts

8. Endosymbiosis - GO
Most membrane-enclosed organelles, including the nucleus, ER and Golgi, probably originated from deep folds in the plasma membrane.
Modern animal and plant cells contain many organelles that serve as compartments for different cellular activities
Mitochondria and chloroplasts originated as bacterial cells that came to live inside larger cells.
Young earth supported many types of bacteria.