Photosynthesis Flashcards

Questions and Answers

What is the overall reaction for photosynthesis?

6 CO2 + 6 H2O + Light → C6H12O6 + 6O2

How does photosynthesis compare to the overall reaction for cellular respiration?

They are opposites. Reactants for photosynthesis are products for cellular respiration, and reactants for cellular respiration are products for photosynthesis.

Where does the energy for photosynthesis come from?

The sun or solar energy.

What plant pigments are involved in photosynthesis?

Chlorophyll pigments Signup and view all the answers

Explain why chlorophyll appears green to us.

Plants absorb the colors orange, red, violet, blue, and some yellows, but they reflect the color green. Signup and view all the answers

How does the amount of energy in light change as the wavelength increases?

As the wavelength increases, energy reduces; as the wavelength decreases, energy increases. Signup and view all the answers

In what organelle of plant cells does photosynthesis take place?

In the chloroplasts. Signup and view all the answers

What are the two stages of photosynthesis?

<ol> <li>Light reactions/light dependent reactions 2. The Calvin cycle/light independent reactions/dark reaction.</li> </ol> Signup and view all the answers

In which part of the chloroplast does each stage of photosynthesis occur?

Light reactions happen in the thylakoid membrane, and the Calvin cycle happens in the stroma. Signup and view all the answers

What happens to water molecules in the light reactions?

It's broken apart and the electrons go to photosystem II. Signup and view all the answers

What photosynthesis waste product is formed in the light reactions?

Oxygen is the waste product in light reactions. Signup and view all the answers

What two products of the light reactions are used up in the Calvin cycle?

NADPH and ATP (or ADP). Signup and view all the answers

What happens to carbon dioxide molecules in the Calvin cycle reactions?

CO2 is converted to sugar. Signup and view all the answers

How can cells store the sugar that is produced in photosynthesis?

They are stored in starch. Signup and view all the answers

What does light reactions produce?

ATP, NADPH, and oxygen as a byproduct. Signup and view all the answers

What is stomata?

Pores in a plant's cuticle through which water and gases are exchanged. Signup and view all the answers

What are mesophyll cells?

A cell that contains a cell wall, nucleus, central vacuole, and chloroplast. Signup and view all the answers

What is a chloroplast?

An organelle where photosynthesis takes place. Signup and view all the answers

What is a thylakoid?

The thylakoid membrane is where photosynthesis is happening. Signup and view all the answers

During the fall, what causes the leaves to change colors?

The green chlorophyll pigments are greatly reduced, revealing other pigments. Signup and view all the answers

What is the Light Independent Reaction?

It occurs in the stroma and involves the conversion of CO2 to glucose using ATP and NADPH. Signup and view all the answers

What is the Light Dependent Reaction?

It happens in thylakoids, where light energy is converted to chemical energy. Signup and view all the answers

Study Notes

Photosynthesis Overview

Photosynthesis overall reaction: 6 CO2 + 6 H2O + Light → C6H12O6 + 6O2
Photosynthesis and cellular respiration are opposite reactions, with reactants and products switching places.

Energy Source

Solar energy is the primary source of energy for photosynthesis.

Plant Pigments

Chlorophyll pigments are essential for capturing light energy during photosynthesis.
Chlorophyll appears green because it reflects green light while absorbing other colors like red, blue, and violet.

Light Energy and Wavelength

Energy inversely relates to wavelength: longer wavelengths have less energy, while shorter wavelengths have more energy.

Cellular Structure

Photosynthesis occurs in chloroplasts, specifically within thylakoid membranes and the stroma.
Light reactions occur in the thylakoid membrane; the Calvin cycle takes place in the stroma.

Light Reactions

Water molecules are split during light reactions, providing electrons to photosystem II.
Oxygen is produced as a waste product in light reactions.
NADPH (electron carrier) and ATP (energy molecule) are produced and utilized in the Calvin cycle.

Calvin Cycle

Carbon dioxide is converted into sugar during the Calvin cycle.
Fixed sugar can be stored as starch.

Stomata and Gas Exchange

Stomata are pores on a plant's surface that facilitate the exchange of gases and water with the atmosphere.

Mesophyll Cells

Mesophyll cells contain chloroplasts and support photosynthesis within the leaf structure.

Chloroplast Structure

Chloroplasts contain an inner and outer membrane, stroma, thylakoids, and granum for photosynthesis.
Thylakoids stack to form granum, increasing surface area for photosynthesis.

Seasonal Changes

In fall, reduced chlorophyll reveals other pigments like carotenoids, causing leaves to change color.

Light Independent Reactions (Calvin Cycle)

Requires products from light-dependent reactions to function.
Enzymatically fixes carbon dioxide into an organic form (glucose) using ATP for energy and NADPH for electron supply.
Converts fixed carbon dioxide, ATP, and NADPH into sugar while reverting ATP to ADP and NADPH to NADP+.

Light Dependent Reactions

Located in the thylakoids where chlorophyll captures solar energy and performs electron transport.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on photosynthesis with these flashcards. The quiz covers the overall reaction, comparison with cellular respiration, and the source of energy for the process. Perfect for students looking to reinforce their understanding of this essential biological process.