PHOTOSYNTHESIS

• PHOTOSYNTHESIS - is the process whereby plants, algae, some bacteria, use the energy of the sun to synthesize organic compounds (sugars) from inorganic compounds (CO2 and water).
• WHY IS PHOTOSYNTHESIS SO

  IMPORTANT?

  • PROVIDES THE OXYGEN WE BREATHE

  • CONSUMES MUCH OF THE CO2

  • FOOD

  • ENERGY

  • FIBERS AND MATERIALS
• GENERAL FORMULA FOR

  PHOTOSYNTHESIS

  6 CO2 + 6H2O ---------> C6H12O6 + 6 O2 + 6 H2O
• Oxygen is being used for aerobic cellular respiration.
• Cellular Respiration: extracting energy from compounds

  (sugars). Formula: C6H12O6 + O2 → 6 CO2 + ATP
• Light is a particle, a bundle of

  electromagnetic energy that moves in

  waves.
• Energy from the SUN reaches the earth in

  the form of Electromagnetic Radiation
• Long Wavelength

  Low Frequency

  Low Energy

  Short Wavelength

  High Frequency

  High Energy
• Visible light -contains just the right

  amount of energy for biological

  reactions
• Light is absorbed by the

  PIGMENTS present in plants.
• Chlorophyll is the most important pigment found in plants.
• A pigment is a substance that

  absorbs some colors of light but reflects others
• PHOTOSYNTHETIC

  pigments

  chlorophyll a

  chlorophyll b
• chlorophyll a – primary pigment in

  plants and cyanobacteria

  -absorbs violet-blue and red light
• chlorophyll b – secondary pigment

  absorbing light

  wavelengths that

  chlorophyll a does not absorb
• ACCESSORY PIGMENTS -

  CHLOROPHYLL B AND CAROTENOIDS
• Light Dependent Reaction -It occur in the thylakoid membrane of

  chloroplast
• Most plants use the Calvin Cycle to

  Convert CO2 into sugars.

  These plants are called C-3 plants
• Enzyme RUBISCO (ribulose bisphosphate carboxylase/oxygenase) is the main enzyme that catalyzes the first reactions of the Calvin Cycle.
• RUBISCO: Is the most abundant protein on earth!
• The Calvin cycle occurs in the stroma of the chloroplast
• The process of diffusion which is the same with osmosis is called CHEMIOSMOSIS
• REDOX happens in cytochrome complex and the energy released from electron is used to pump H+ from the stroma into the Thylakoid membrane.
• As the water molecules split, a molecule of Oxygen and Hydrogen ions are released in a process called PHOTOLYSIS
• When a photon of light strikes a molecule of photosystem II, the light

  energy excites or boosts an electron out of place and to a higher energy level. This process is called

  PHOTOACTIVATION
• Fermentation - biochemical process that gets energy from carbohydrates and does not need oxygen
• ATP Synthase - enzyme responsible for synthesizing ATP during cellular respiration
• Two types of fermentation

  1. Alcohol fermentation - ethanol and carbon dioxide
  2. lactic acid fermentation - lactic acid
• Anaerobic respiration -uses electron receptor other than oxygen
• anaerobic fermentation -is very useful in food industry
• Photo -produced by light
• Synthesis - a whole made of parts put together
• Energy from the sun that reaches the Earth in form of ELECTROMAGNETIC RADIATION
• Electromagnetic radiation -formed by different types of waves
• Waves -a disturbance that carries energy
• Black -is bot a color of light, its the absence of light
• Plant pigments:

  1. Photosynthetic pigment 2.protective pigment
• Chlorophyll A -primary pigment in plants
• Chlorophyll B -secondary pigment; sita ang nag aabsorb ng di naabsorb ng chlorophyll A
• accesory pigments -helps transfer some energy to chlorophyll A