Photosynthesis 4

Photosynthesis 4

By R. Marsh Ph.D.

Photosynthesis is a REDOX REACTION

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It reverses the direction of electron flow in cellular respiration

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H₂O is OXIDIZED (loses an electron)

CO₂ is REDUCED (gains electrons) to make SUGAR

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The process requires energy (provided by light)

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REDOX Reaction

In the reaction, we can see:

Carbon dioxide (CO₂) is reduced to carbohydrates

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Water (H₂0) gets oxidized to oxygen

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The energy is provided by the sunlight for this reaction.

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REDOX Reaction

Multiple Choice

2.The function accomplished by the light-dependent reactions is ______________.

• Energy and electron storage

• Sugar production

• Carbon fixation

• Conversion of sugar

Multiple Choice

Where does light dependent specifically occur?

• thylakoid membrane of the grana

• Stroma of the chloroplast

• mitochondria

• nuclear membrane

Multiple Choice

•An enzyme that fixes carbon from atmosphere to convert it to complex macromolecule glucose.

• RuBP (Ribulose bisphosphate)

• RuBisCo (Ribulose Bisphosphate Carboxylase)

• PGA (3-Phosphoglycerate)

• G3P (Glyceraldeyhyde 3-Phosphate)

Multiple Choice

•Plants and plant-like organisms make their own food or energy (glucose) from sunlight.

• Chemotrophs

• Heterotrophs

• Autotrophs

• Saprophytes

Multiple Choice

•The organelle responsible for photosynthesis:

• Vacuole

• Chloroplast

• nuclear membrane

• mitochondria

• Cytoplasm

Multiple Choice

Main products of the Calvin Cycle

• Oxygen, NADP+, ADP

• Glucose, CO2, ADP

• ADP, NADP+, Glucose

• ATP, NADPH, Oxygen