1. Unit 2 Notes: Endosymbiotic Theory

2. (1) Endosymbiotic Theory
Modern eukaryotic cells evolved from free-living prokaryotic cells living symbiotically with larger unicellular organisms.
Symbiotically??
The cells lived and worked together because they benefited from the relationship.

3. (2) Summarizing the Theory
Chloroplasts + Mitochondria were once free-living bacterial cells (prokaryotes).
The chloroplasts + mitochondria benefited from living with larger prokaryotes.
The larger prokaryotes took the chloroplasts + mitochondria inside their cell.
TA-DA!  The Modern Day Eukaryotic Cell

6. (3) Evidence for the Theory
Chloroplasts, Mitochondria, ….
Have their own fully developed cell membranes.
Have their own copy of DNA.
Can replicate themselves, all on their own.
They have their own ribosomes.
They produce their own proteins.
They can exist/survive on their own w/o a larger cell.

7. (4) Other Examples Like This…
Bobtailed Squid + Glowing Bacteria
Aphids + Digestive Bacteria
Spotted Salamander + Algae