Photosynthesis & Cellular Respiration

Chapter 9

The Need for Energy (9.1)

• All organisms need ENERGY

• Plants (autotrophs) obtain energy from the sun

• Other organisms (heterotrophs) eat plants to get the plant’s stored energy

ATP• Adenosine Triphosphate =

1 adenosine molecule, 1 ribose molecule, + 3 phosphate groups

• Energy is stored in the bonds between the phosphates

• When the bond breaks, energy is released

• Phosphate can be reattached to ‘recharge’ the ATP molecule

Photosynthesis (9.2)

• Photosynthesis = plants use sunlight energy, carbon dioxide, and water to make simple sugars (glucose)

Sunlight + 6CO2 + 6H2O C6H12O6 + 6O2

• Oxygen also gets produced which we take advantage of!!!

Inputs/Reactants Outputs/Products

Chloroplasts & Pigments• Chloroplasts: where photosynthesis takes place

(contains chlorophyll)

• This means only plants goes through photosynthesis

• Pigments = compounds that absorb light• Visible Light made up of a range of colors– ROY G BIV

• Colors that don’t get absorbed, are reflected, and are what you see

• Chlorophyll give plants their green color, helps the plant absorb energy from sunlight!!!

• Carotenoids pigments in plants that become visible when plants stop producing chlorophyll

You need to know how to fill in this diagram!!! HONOR’S students need to be able to compare and contrast (at least 3 similarities and 3 differences) the “Light Reactions” and the “Calvin Cycle/Light Independent Reactions.”

Cellular Respiration (9.3)

• Cellular Respiration = mitochondria break down food molecules (glucose) and use oxygen to produce ATP

C6H12O6 + 6O2 6CO2 + 6H2O + 36 ATP

– CO2 also get produced as a waste product

– Plants use the CO2 to make glucose

• Glycolysis = breaking down glucose to use its pieces to make energy, occurs in the cytoplasm

Inputs/Reactants Outputs/Products

• Respiration begins in the cytoplasm and ends inside the mitochondria where the ATP is produced

• Respiration occurs in both plant cells and animal cells

• Aerobic = requires oxygen– Aerobic respiration produces the most ATP (36

total ATP per molecule of glucose)

• Anaerobic = no oxygen required– Fermentation = anaerobic respiration, not as

efficient1. Lactic Acid Fermentation produces 2 ATP & Lactic Acid2. Alcoholic Fermentation produces 2 ATP & CO2