Photosynthesis

What is photosynthesis?

The process where plants, algae, and some bacteria use sunlight to make organic compounds (glucose).

What type of energy conversion occurs in photosynthesis?

Light energy is converted into chemical energy stored in glucose.

What is the word equation for photosynthesis?

Carbon dioxide + water → glucose + oxygen

What is the balanced chemical equation for photosynthesis?

6CO_2​+6H₂​O→C₆​H₁₂​O₆​+6O₂​

Where does carbon dioxide for photosynthesis come from?

The atmosphere (air).

Where does water for photosynthesis come from?

The soil.

What provides the energy for photosynthesis?

Sunlight.

What is glucose?

A sugar that stores chemical energy for the plant.

What happens to the oxygen produced in photosynthesis?

It is released into the atmosphere.

Why are light and chlorophyll written above the equation arrow?

They facilitate the reaction but are not reactants or products.

Where does photosynthesis occur?

In the chloroplasts.

What is chlorophyll?

A green pigment that absorbs light energy.

Where is chlorophyll found?

In the thylakoid membranes/discs of chloroplasts.

Which organisms carry out photosynthesis?

Plants, algae, and some bacteria.

What is carbon fixation?

The conversion of carbon from carbon dioxide into glucose.

What are the two stages of photosynthesis?

Light-dependent reactions and light-independent reactions

Where do light-dependent reactions occur?

In the thylakoid membranes.

What happens during the light-dependent reactions?

Light energy is absorbed, water is split, oxygen is released, and ATP is produced.

What gas is released when water is split during photosynthesis?

Oxygen

What happens to the hydrogen produced from splitting water?

It moves into the stroma to help make glucose.

What is ATP’s role in photosynthesis?

ATP provides energy for the light-independent reactions.

Where do light-independent reactions occur?

In the stroma of the chloroplast.

What happens during the light-independent reactions?

Carbon dioxide combines with hydrogen using ATP energy to form glucose.

Do light-independent reactions require sunlight directly?

No, but they rely on ATP made during the light-dependent reactions.

What is the stroma?

The fluid-filled space inside chloroplasts surrounding the thylakoids.

What is a limiting factor?

A factor that slows the rate of photosynthesis when it is in short supply.

How does light intensity affect photosynthesis?

Increasing light intensity increases the rate until the optimum rate is reached.

Why does photosynthesis depend on light?

Light energy is needed to split water and produce ATP.

How does carbon dioxide concentration affect photosynthesis?

Increasing carbon dioxide increases the rate until another factor becomes limiting.

Why is carbon dioxide important in photosynthesis?

It provides the carbon used to make glucose.

How does temperature affect photosynthesis?

Temperature affects the enzymes that control photosynthesis.

What happens to photosynthesis at very low temperatures?

Enzymes work slowly, so photosynthesis slows down.

What happens to photosynthesis at very high temperatures?

Enzymes can denature, causing the rate to decrease.

What is the optimum temperature?

The temperature at which photosynthesis occurs at the fastest rate.

During the day, what is often the limiting factor for photosynthesis?

Carbon dioxide concentration.

Why are chloroplasts important?

They are the organelles where photosynthesis occurs.

Why is photosynthesis important for ecosystems?

It provides food and oxygen for most living organisms.

Why is photosynthesis important for the carbon cycle?

It removes carbon dioxide from the atmosphere and stores carbon in glucose.

What is the main purpose of photosynthesis?

Make glucose

Which organelle carries out photosynthesis?

Chloroplast

Which pigment absorbs light energy?

Chlorophyll

What are the reactants of photosynthesis?

Carbon dioxide and water

Which product of photosynthesis is released into the atmosphere?

Oxygen

Where do the light-dependent reactions occur?

Thylakoids

What is produced during the light-dependent reactions?

Oxygen and ATP

Where do light-independent reactions occur?

Stroma

Which molecule stores chemical energy made in photosynthesis?

Glucose

Which factor can limit the rate of photosynthesis?

Light intensity

Why does temperature affect photosynthesis?

It affects enzymes

What happens if carbon dioxide concentration increases?

Photosynthesis rate may increase

Which organisms can photosynthesise?

Plants, algae, and some bacteria

What is carbon fixation?

Converting carbon dioxide into glucose carbon

Which statement about light-independent reactions is correct?

They occur in the stroma

Photosynthesis converts light energy into chemical energy. - T/F

TRUE

Glucose is produced during photosynthesis. - T/F

TRUE

Oxygen is a reactant in photosynthesis. - T/F

FALSE

Chlorophyll absorbs light energy. - T/F

TRUE

Photosynthesis occurs in chloroplasts. - T/F

TRUE

Thylakoids contain chlorophyll. - T/F

TRUE

Plants are the only organisms that photosynthesise. - T/F

FALSE

Carbon dioxide comes from the atmosphere. - T/F

TRUE

Water used in photosynthesis usually comes from the soil. - T/F

TRUE

ATP is produced during the light-dependent reactions. - T/F

TRUE

Light-independent reactions occur in the stroma. - T/F

TRUE

Light-independent reactions directly require sunlight. - T/F

FALSE

Carbon fixation converts carbon dioxide into glucose carbon. - T/F

TRUE

Increasing light intensity can increase photosynthesis rate. - T/F

TRUE

Extremely high temperatures can reduce photosynthesis. - T/F

TRUE

Photosynthesis depends on enzymes. - T/F

TRUE

Carbon dioxide can be a limiting factor for photosynthesis. - T/F

TRUE

Oxygen is produced when water molecules are split. - T/F

TRUE

Chloroplasts are found in animal cells. - T/F

FALSE

Photosynthesis is important in the carbon cycle. - T/F

TRUE