This has been the 1469th visit to this site since Oct. 10, 1996.

Word roots:

auto (G) = self, as in autotroph, automobile
hetero (G) = other, different, as in heterotroph, heterosexual
tropho (G) = eat, food

AUTOTROPHIC AND HETEROTROPHIC NUTRITION (pp. 182-183 & 505-506)

AUTOTROPHS = CO2 as C source

2 types
1) Photoautotrophs = light as energy source (plants, photosynthetic bacteria and algae)
2) Chemoautotrophs = oxidation of inorganic molecules as energy source (certain bacteria)

1) Photoheterotrophs = too weird to talk about (only certain bacteria can do this)
2) Chemoheterotrophs = e.g. animals (us), fungi, many bacteria and archaebacteria.

PHOTOSYNTHESIS (Chapter 10)

Transforms light energy into chemical bond energy (e.g. in glucose)
(See FIG. 9.1 as review)
Synthesizes energy rich molecules from energy poor CO2 and H2O
= How plants make food Overall reaction:

Takes place in chloroplasts or photosynthetic bacteria.
CHLOROPHYLL is the green pigment that drives photosynthesis its located in the thylakoid membranes (site of "light reactions) of the Chloroplast. (Fig. 10.2)
Most chloroplasts are in the mesophyll of the leaf (FIG. 10.2)
Prokaryotes don't have chloroplasts; chlorophyll is in plasma membrane and/or internal membranes.

The 2 stages of Photosynthesis:

1) Light reaction (in thylakoid membrane)
2) Calvin cycle (= Dark reaction) (occurs in the stroma)

OVERVIEW OF PHOTOSYNTHESIS = (FIG. 10.4)

ATP and reducing power from Light Reaction used to reduce CO2 during Calvin Cycle.

LIGHT REACTION = Converts light energy into energy stored in NADPH and ATP

Occurs in thylakoid membranes
Gives off O2 from splitting of water
ATP formed via PHOTOPHOSPHORYLATION

CALVIN CYCLE = Assimilation (fixation) and reduction of CO2 to sugars

Occurs in the Stroma
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