Lecture 19

Question 1

Define Photosynthesis

Answer 1

The biochemical process of building Carbohydrates from sunlight, carbon dioxide, and water

Question 2

Describe the structure of chloroplasts and their role in Photosynthesis

Answer 2

Structure:
-Double membrane
-Thylakoid membrane = highly folded membrane inside the outer & inner membranes
-Grana = flattened sacs that are grouped into stacks; formed by thylakoid membranes
-Lumen = space inside grana
-Stroma = area outside grana
Role:
-Site of photosynthesis

Question 3

Know the main type of electron carrier in Photosynthesis

Answer 3

NADPH (reduced form)

Question 4

Know the two phases of Photosynthesis and describe what happens during each phase

Answer 4

Light Reactions (photo part):
Occur in the thylakoid membrane
H2O is split
O2 is released
NADP+ is reduced to NADPH
ATP is generated from ADP by photophosphorylation
Calvin Cycle (synthesis part):
Occurs in stroma
Formation of sugar from CO2 using ATP and NADPH

Question 5

Know the relationship between the light reactions and the Calvin Cycle

Answer 5

Light reactions produce ATP and NADPH (energy) that is used to synthesize carbohydrates from CO2 in the Calvin cycle

Question 6

*Know and describe the three phases of the Calvin Cycle, including the intermediates that we cover in class

Answer 6

Phase 1 → Carbon fixation
Phase 2 → Reduction
Phase 3 → RuBP Regeneration