Photosynthesis

 

• Photosynthesis is the process by which plants make food. 
• Algae are the group of unicellular or multicellular organisms. Algae and the blue green algae which are prokaryotes obtain nutrients through photosynthesis.
• Photosynthesis has two phases. - Light phase, Dark phase

Light phase

• Takes place in grana.
• Takes place in the presence of light.
• Water splits into hydrogen and oxygen.
• Expels oxygen.
• Hydrogen reaches stroma.
• ATP, the energy molecule is formed.

Dark phase

• Takes place in stroma.
• Light is not used.
• Hydrogen and energy (ATP) required for this phase is obtained from light phase.
• Glucose is formed by combining. hydrogen and carbon dioxide.

Melvin Calvin

• He was awarded Nobel Prize in Chemistry in 1961 for explaining the reactions in the dark phase