Photosynthesis Overview

Overview of 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.
• Importance: Photosynthesis is the basis of life on Earth, providing energy and organic compounds for the food chain.

Light-Dependent Reactions

• Occur in thylakoid membranes of chloroplasts
• Light energy excites electrons, which are transferred to electron acceptors
• Generates ATP and NADPH
• Two stages:
  1. Light-harvesting complexes absorb light energy
  2. Electron transport chain produces ATP and NADPH

Light-Independent Reactions (Calvin Cycle)

• Occur in stroma of chloroplasts
• Carbon fixation: CO2 is fixed into organic compounds using ATP and NADPH from light-dependent reactions
• Regeneration of RuBP, the acceptor molecule for CO2
• Produces glucose (C6H12O6) and oxygen

Factors Affecting Photosynthesis

• Light intensity: Increased light intensity increases photosynthesis rate
• Temperature: Optimal temperature range for photosynthesis is between 20-30°C
• Water availability: Water is necessary for photosynthesis, but excessive water can limit CO2 uptake
• CO2 concentration: Increased CO2 concentration increases photosynthesis rate

Types of Photosynthesis

• Oxygenic photosynthesis: Produces oxygen as a byproduct, characteristic of plants, algae, and cyanobacteria
• Anoxygenic photosynthesis: Does not produce oxygen, characteristic of some bacteria

Importance of Photosynthesis

• Provides energy and organic compounds for the food chain
• Supports aquatic life by producing oxygen and organic compounds
• Regulates Earth's atmosphere by removing CO2 and releasing O2

Photosynthesis Overview

• Photosynthesis is the process by which plants, algae, and some bacteria convert light energy into chemical energy, producing organic compounds like glucose.

Light-Dependent Reactions

• Take place in thylakoid membranes of chloroplasts
• Light energy excites electrons, which are transferred to electron acceptors
• Produce ATP and NADPH through two stages:
  • Light-harvesting complexes absorb light energy
  • Electron transport chain produces ATP and NADPH

Light-Independent Reactions (Calvin Cycle)

• Occur in stroma of chloroplasts
• Fix CO2 into organic compounds using ATP and NADPH from light-dependent reactions
• Regenerate RuBP, the acceptor molecule for CO2
• Produce glucose (C6H12O6) and oxygen

Factors Affecting Photosynthesis

• Light intensity: Increased light intensity increases photosynthesis rate
• Temperature: Optimal temperature range for photosynthesis is between 20-30°C
• Water availability: Water is necessary, but excessive water can limit CO2 uptake
• CO2 concentration: Increased CO2 concentration increases photosynthesis rate

Types of Photosynthesis

• Oxygenic photosynthesis: Produces oxygen as a byproduct, characteristic of plants, algae, and cyanobacteria
• Anoxygenic photosynthesis: Does not produce oxygen, characteristic of some bacteria

Importance of Photosynthesis

• Provides energy and organic compounds for the food chain
• Supports aquatic life by producing oxygen and organic compounds
• Regulates Earth's atmosphere by removing CO2 and releasing O2

Learn about photosynthesis, the process by which plants and some bacteria convert light energy into chemical energy, and its importance in the food chain.