Chapter 14 (Exam 4) Powerpoint Summarized - Molec Cell Bio

Photosynthesis

builds sugars using sunlight

Respiration

breaks down sugars by oxidation

• USES O2

• releases CO2 & H2O

Prokaryotes use photosynthesis in their

plasma membranes

Plants use photosynthesis in their

chloroplasts

Thylakoids contain

chlorophyll and photosynthesis proteins

The stroma

surrounds thylakoids

Chlorophyll and light absorption is embedded in

thylakoid membranes via hydrocarbon tails

The Calvin cycle takes place in

the stroma

Photosystem I takes place in

the outer thylakoid membrane

Photosystem II takes place in

embedded in the thylakoid membrane

In PSII, electrons that are energized

are sent through the ETC to generate ATP

In PSI, energized electrons

go through another ETC to generate NADPH

What is the electron flow in photosynthetic electron transfer (PSII & PSI)?

H2O → PSII → ETC → PSI → NADPH

• products: ATP and NADPH

In the Calvin Cycle, it uses

ATP and NADPH to fix carbon from CO2 into sugars

Calvin cycle steps

1. carbon dixation by rubisco

2. reduction to form 3-carbon sugar (G3P)

3. regeneration of rubisco’s substrate RuBP

G3P can be turned into

• glucose and sucrose

• cellulose

• starch, oils