Lecture 18

Question 1

Name the group in which photosynthesis evolved

Answer 1

bacterial lineage - cyanobacteria

Question 2

Explain how other groups acquired the ability to photosynthesize

Answer 2

• eukaryotic lineages engulfed cyanobacteria (endosymbiosis)
• not digested but instead transformed into organelle

Question 3

Explain the difference between primary, secondary, and tertiary endosymbiosis,
and for each, provide an example of a group in which it occurred

Answer 3

1. primary endosymbiosis occured in common ancestor to red and green algae
2. secondary emdosymbiosis, a free-living algal cell is transformed into chlorplast
3. some dinoflagellates acquired chloroplasts through tertiary endosymbiosis