Photosynthesis and Cellular Respiration The building and breaking down of glucose

Photosynthesis The process in which plants obtain energy from sunlight and transform it into chemical energy Autotrophs –are able to undergo PSN- plants, algae, and some bacteria The ultimate source of energy is sunlight

PSN continued Goal of the process: GLUCOSE (for energy) Plants need CO 2, H 2 0, and Light End Result – O 2 and C 6 H 12 O 6 (Glucose)

PSN Equation 6H 2 O + 6CO 2 + Light  C 6 H 12 O 6 + 6O 2 Takes place in the chloroplast Chlorophyll (green pigment) and other pigments are the chemicals that allow absorb light to form energy

PSN Equation… 6H 2 O + 6CO 2 + Light  C 6 H 12 O 6 + 6O 2 Reactants Water Carbon Dioxide Light energy Products Glucose Waste product – Oxygen The waste oxygen ultimately comes from the water molecule

Parts of PSN Light Absorption The pigments absorb the light in the cholorophyll Electron Transport Chain The light “excites” electrons. The electrons are passed on and on giving off energy every time they switch hands, eventually forming a chemical called NADPH. Calvin Cycle NADPH enters the Calvin Cycle. After a series of reactions the NADPH is converted to Glucose

Light White light from the sun is a combination of colors – visible spectrum Result Substances can reflect, absorb, or transmit the different colors The color of an object is the result of that object reflecting a certain color. i.e. chlorophyll absorbs reds and blues and reflects green.

Cellular Respiration The process of breaking down glucose to obtain energy in the form of ATP Has two parts: Glycolysis Fermentation / Aerobic Respiration 6O 2 + C 6 H 12 O 6  6CO 2 + 6H 2 O+ Energy (ATP) OPPOSITE OF PHOTOSYNTHESIS

Glycolysis The first stage of Cell Respiration A glucose molecule is broken down into two pieces called pyruvate Doesn’t need oxygen Occurs in the cytoplasm End Result 2 ATP molecules

If Oxygen is Present Aerobic Respiration – oxygen present Pyruvate enters into the Krebs Cycle Series of reactions yields other chemicals (NADPH) that will be used later and ATP Electron Transport Chain – The chemicals produced in the Krebs Cycle are used to pass electrons down a long series of acceptors End result  34 ATP molecules

If Oxygen is Absent Pyruvate enters into Fermentation Fermentation converts pyruvate into other chemical compounds that do not yield ATP but other chemicals that the body can use. Example: Lactic Acid  when not enough Oxygen present the body converts pyruvate into Lactic Acid= sore muscles

Glucose Glycolysis Oxygen PresentOxygen Absent Fermentation (anerobic) Aerobic Respiration 34ATP 2 ATP