Photosynthesis

formula for photosynthsis

6CO2 + 12H2O + light energy → C6H12O6 + 6O2 + 6H2O

chloroplast structure

stroma — fluid matrix inside a chloroplast, contains enzymes for light-independent stage

granum — stacks on thylakoids. it is where light is absorbed and ATP is synthesised during light dependent stage

light-dependent stage

• first stage of photosynthesis

• occurs in the thylakoids of chloroplasts

• requires light

  1. chlorophyll absorbs light and transfers it to the photosystem

  2. hydrolysis splits the water molecule into hydrogen ions and electrons, as well as oxygen

  3. the protons and electrons are used to produce NADPH and ATP

  4. Chlorophyll regains lost electrons from water molecules in photolysis?

formula: 2H₂O + 2NADP+ + 3ADP + 3Pi → O₂ + 2NADPH + 3ATP

photosynthesis

the process by which some protists and bacteria, and all plants produce glucose required for ATP making, in a process known as cellular respiration

light independent

• 2nd stage of photosynthesis

• happens in the stroma

• doesn’t require sunlight

  1. CO2 enters the leaf via pores called the stomata and diffuses in the stroma

  2. enzymes change inorganic CO2 into a more usable form

  3. The ATP from the light-dependent reaction helps supply energy

  4. The NADPH from the light-dependent reaction supplies reducing power, meaning it supplies high-energy electrons

  5. The fixed CO2, ATP and NADPH create a product that can be converted to glucose. water

formula: 2 NADPH + 18 ATP + 6 CO₂ → C₆H₁₂O₆ + 12 NADP⁺ + 18 ADP + 18 P_i + 6 H₂O

factors that affect rate of photosynthesis

• amount of CO2

• light intensity and wavelength

• temperature (Calvin only)

• water availability

• chlorophyll