Bio Exam Review

Question 1

Secondary endosymbiosis

Answer 1

• green algae or red algae are endosymbionts
• green algae yields euglenoids
• red algae yields brown algae
• 3 membranes on chloroplasts

Question 2

Tertiary endosymbiosis

Answer 2

• brown algae endosymbiont

- dinoflagellates

Question 3

Transition to land challenges

Answer 3

1. Avoid drought and desiccation (cuticle)
2. Endure exposure to high light (pigments can selectively absorb or dissipate heat, chloroplasts can move to avoid direct sunlight)
3. Take in oxygen and carbon dioxide
4. Protect and disperse gametes and progeny
5. Obtain and transport water and nutrients (mycorrhizae)
6. Have structural support

Question 4

Primary endosymbiosis

Answer 4

• free living, photosynthetic cyanobacterium engulfed by a larger cell.
• Cyanobacteria continues to photosynthesize within cell
• green algae and red algae result
• chloroplast has 2 membranes