Metabolism-Honors Biology

Photosynthesis : Chemical reaction in which light energy is converted to chemical energy.

Chloroplasts are the organelles where photosynthesis occur in plants and make them green.

EQUATION FOR PHOTOSYNTHESIS!! 6CO2+6H2O=C6H12O6+6O2

Word equation: Carbon dioxide + water =(light, chlorophyll)= Glucose(sugar)+oxygen

Thylakoid- a single flatten green coin

Granum- the whole stack of the flatten green coin

The light reaction- occurs in thylakoid membrane (happens inside)

The Calvin cycle- occurs in the stroma

ATP and ADPThe light dependent reaction

  • Thylakoid has Photosystem, photosystem has chlorophyll (the green dots)

The light-dependent reaction process:

  1. The sunlight hits photosystem II (PSII) chlorophyll pigment and excites the electrons that move through the Electron Transport Chain (ETC). They carry energy that passes to photosystem I (PSI).

  2. The lost electrons come from H2O, which splits into 2 hydrogen ions, 2 electrons and 1 oxygen atom, there, oxygen is released into the air.

  3. The electrons lose energy moving along the ETC, the energy is used to pump hydrogen ions from the Stroma into the Thylakoid.

  4. The Thylakoid lake becomes high concentration hydrogen ions that contain energy. The hydrogen will move from high to low concentration by diffusion. They move out into the stroma using the enzyme ATP synthase. As they pass through, it causes ADP to get phosphorylated to become ATP, releasing energy in the process, and will be used in the Calvin cycle.

  5. Sunlight hits PSI that re-energize the electrons, passing onto an electron shuttle molecule called NADP+. The energized electrons and the Hydrogen molecule are used to reduce NADP+ into NADPH and carry them to the Calvin cycle.