Photosynthesis: Light Dependent and Independent Stages

Flashcards covering the stages of photosynthesis, the differences between C3, C4, and CAM plants, and the role of Rubisco.

In which specific part of the chloroplast does the light-dependent stage occur?

The Thylakoid (which has chlorophyll).

What is the primary function of a photon in the light-dependent stage?

To change chemical batteries from $ADP$ to $ATP$ and $NADP^+$ to $NADPH$.

Where does the light-independent stage, also known as the Calvin cycle or carbon fixation, take place?

The Stroma (which has no chlorophyll).

What are the two forms of the ultimate product of photosynthesis mentioned in the text?

Glucose ($6$ carbon) and G3P ($3$ carbon).

What is the main characteristic identifying a C3 plant during the Calvin cycle?

A $3$ Carbon-Molecule enters the Calvin cycle.

What is the main characteristic identifying a C4 plant during the Calvin cycle?

A $4$ Carbon-Molecule enters the Calvin cycle.

How do C4 plants handle carbon prior to use in the Calvin cycle?

They store carbon as an acid.

What is the specialized behavior of CAM plants (like cacti) regarding their stomata?

They close their stomata during the day and gas exchange only happens at night.

What is the full name of the enzyme Rubisco?

Ribulose [1,5] bisphosphate Carboxylase Oxygenase.

In the Calvin cycle, what is the ratio of G3P outputs to G3P molecules that go back into the cycle?

$1$ G3P as an output for every $5$ G3P's that go back into the cycle.

What is the result of Rubisco acting as an Oxygenase?

Photorespiration, which uses up energy.

Rubisco acts as a Carboxylase to work on which molecule?

$CO_2$ during the Calvin cycle (photosynthesis).

According to the transcript, what is technically the output of photosynthesis?

Glucose.

What is the overall, fully balanced equation for photosynthesis as provided in the lecture notes?

$$6CO_2 + 12H_{2}O \rightarrow C_{6}H_{12}O_{6} + 6O_2 + 6H_{2}O$$

What are the three specific inputs required for the light-dependent stage?

$H_{2}O$, $ADP + Pi$, and $NADP^+$.

What are the three outputs of the light-dependent stage?

$ATP$, $NADPH$, and $O_2$ (byproduct).

What are the inputs required for the light-independent stage (Calvin cycle)?

$CO_2$, $ATP$, and $NADPH$. instrument.

What are the outputs of the light-independent stage?

$C_{6}H_{12}O_{6}$ (via G3P), $ADP + Pi$, and $NADP^+$.

What occurs during photorespiration, which is considered a main factor for Rubisco's inefficiencies?

Rubisco attaches to $O_2$ instead of $CO_2$, which uses up energy.

What two activities occur in CAM plants during the day while their stomata are closed?

They run the Calvin cycle and light-dependent stage.