Photosynthesis Process Quiz

Photosynthesis

Definition

• Process by which plants, algae, and some bacteria convert light energy from the sun into chemical energy in the form of organic compounds, such as glucose.

Overall Equation

• 6 CO2 + 6 H2O + light energy → C6H12O6 (glucose) + 6 O2

Steps of Photosynthesis

• Light-Dependent Reactions
  • Occur in the thylakoid membranes of the chloroplast
  • Light energy excites electrons, which are used to generate ATP and NADPH
  • Water is split into oxygen and hydrogen ions
• Light-Independent Reactions (Calvin Cycle)
  • Occur in the stroma of the chloroplast
  • ATP and NADPH are used to convert CO2 into glucose
  • Regeneration of RuBP (ribulose-1,5-bisphosphate) for continued CO2 fixation

Important Molecules

• Chlorophyll
  • Green pigment that absorbs light energy
  • Found in the thylakoid membranes of the chloroplast
• RuBP (Ribulose-1,5-bisphosphate)
  • Five-carbon sugar that plays a key role in the Calvin Cycle
  • Binds to CO2, forming a six-carbon intermediate
• ATP and NADPH
  • Energy-rich molecules produced in the light-dependent reactions
  • Used to fuel the light-independent reactions

Factors Affecting Photosynthesis

• Light Intensity
  • Increased light intensity can increase photosynthesis rates
  • However, high intensities can lead to photoinhibition
• Temperature
  • Optimal temperature range for photosynthesis varies between species
  • Higher temperatures can lead to water loss and decreased photosynthesis
• Water Availability
  • Drought can limit photosynthesis by reducing water availability
  • Plants have adapted mechanisms to conserve water and maintain photosynthesis

Photosynthesis

Definition

• Process that converts light energy into chemical energy in the form of organic compounds, such as glucose.

Overall Equation

• 6 CO2 + 6 H2O + light energy → C6H12O6 (glucose) + 6 O2

Steps of Photosynthesis

Light-Dependent Reactions

• Occur in thylakoid membranes of chloroplast
• Light energy excites electrons, generating ATP and NADPH
• Water is split into oxygen and hydrogen ions

Light-Independent Reactions (Calvin Cycle)

• Occur in stroma of chloroplast
• ATP and NADPH convert CO2 into glucose
• RuBP regeneration for continued CO2 fixation

Important Molecules

Chlorophyll

• Green pigment that absorbs light energy
• Found in thylakoid membranes of chloroplast

RuBP (Ribulose-1,5-bisphosphate)

• Five-carbon sugar that plays a key role in Calvin Cycle
• Binds to CO2, forming a six-carbon intermediate

ATP and NADPH

• Energy-rich molecules produced in light-dependent reactions
• Fuel light-independent reactions

Factors Affecting Photosynthesis

Light Intensity

• Increased light intensity can increase photosynthesis rates
• High intensities can lead to photoinhibition

Temperature

• Optimal temperature range for photosynthesis varies between species
• Higher temperatures can lead to water loss and decreased photosynthesis

Water Availability

• Drought can limit photosynthesis by reducing water availability
• Plants have adapted mechanisms to conserve water and maintain photosynthesis

Test your knowledge of photosynthesis, the process by which plants and some organisms convert light energy into chemical energy, including the light-dependent reactions and overall equation.