Chapter 10 [Photosynthesis Light Reactions]

In photosynthesis, _____ is reduced while _____ is oxidized.

CO2, H2O

Q//Which types of organisms use photosynthesis? Which types of organisms use cellular respiration?

-Photosynthesis: Plants

-Celluar Respiration: Plants + Animals

Q//What is one use for glucose besides making ATP?

Glucose is not only used to produce ATP for energy but also serves as a vital building block for the cell. It can be stored as starch in plants or glycogen in animals for later energy use. Glucose is also essential for making structural molecules, such as cellulose in plant cell walls, which provides strength and support. Additionally, cells can convert glucose into amino acids, fatty acids, and nucleotides, which are needed to build proteins, lipids, and DNA or RNA. In this way, glucose supports both energy storage and the growth and maintenance of cellular structures.

Where do light-independent reactions of photosynthesis take place in a chloroplast?

Stroma

What products of the light-dependent reactions are used in the Calvin-Benson cycle (light-independent reactions)?

-ATP

-NADPH

-CO2

Which of the following types of electromagnetic radiation has the most energy?

UV

Chlorophyll appears green because...

It reflects green light and absorbs blue and red

Q//What would happen to electrons in chlorophyll if you exposed them to green light?

The energy from green light isn't transferred to the electrons, so they remain in their ground state and don't jump to a higher energy level.

Which of the following describes the transfer of energy from an excited electron to a nearby molecule?

Resonance Transfer

Which consequence of electron excitation do you think would be the LEAST likely to happen in a chloroplast? Why?

The least likely consequence of electron excitation in a chloroplast is the release of energy as fluorescence or heat. This is because chloroplasts are highly efficient at using excited electrons for photosynthesis. Most of the energy from light absorbed by chlorophyll is transferred through resonance to the reaction center and then passed along the electron transport chain to drive redox reactions that produce ATP and NADPH. Releasing energy as light or heat is essentially wasted energy, so chloroplasts have evolved mechanisms to minimize this loss, making it the least likely outcome under normal conditions.

Which of the following is true about Photosystem II (PSII)?

-Electrons from PQ are transferred through an electron transport chain to generate ATP

-Electrons are passed from PSII to PQ

How is ATP made in the chloroplast?

Higher concentrations of H+ in the thylakoid lumen

Where do electrons come from to regenerate the electrons at the reaction center of PS II?

H2O

In linear flow, where do excited electrons from PS II go?

Reaction center of PS I

In linear flow, where do the excited electrons from PS I go?

NADPH

What is produced from linear flow of photosynthesis?

-O2

-ATP

-NADPH

In cyclic flow, where do the excited electrons from the reaction center of PS I go?

Back to the reaction center after being passed to PC