Photosynthesis

Question 1

Photosynthesis definition

Answer 1

The process by which organisms transform light into chemical energy.

Question 2

What are the two reactions of photosynthesis?

Answer 2

The light-dependent reaction, and the light-independent reaction

Question 3

What is the light independent reaction also known as?

Answer 3

The Calvin Cycle

Question 4

What is the light-dependent reaction?

Answer 4

In the thylakoids of a chloroplast, light is absorbed and two electrons are excited in the PSII. The electrons move through the electron transport chain and they begin to lose energy. An electrochemical gradient is established. The electrons then are passed to PSI, and absorbed light re-energizes them. The re-energized electrons are passed to an electron acceptor where they come together with a hydrogen ion and form NADPH. Lost electrons are replaced in the PSII by the splitting of water molecules. The water is split into 2 hydrogen ions, 2 electrons, and 1 oxygen atom. This oxygen is considered waste and is released by the plant. Hydrogen ions diffuse from high to low concentration out of the thylakoid, and into the stroma.

Question 5

What does PSII stand for?

Answer 5

Photo system 2

Question 6

What does PSI stand for?

Answer 6

Photo system 1

Question 7

What is the Calvin Cycle?

Answer 7

Depends on the production of ATP and NADPH from the light dependent cycle. ATP and NADPH are used to convert carbon dioxide into glucose.

Question 8

Where does the light-dependent reaction take place?

Answer 8

The thylakoids

Question 9

Where does the Calvin Cycle take place?

Answer 9

The stroma.

Question 10

Photosynthesis Equation

Answer 10

Carbon Dioxide + Water = Glucose + Oxygen

CO2 + H2O = C6H12O6 + O2