 Remember, any late/msg work is due tomorrow from
the months of Nov & Dec.
 Take out the photosynthesis notes you took before
break.
 Review your notes and answer the following in you
notebook:
1.
2.
In which organelle does photosynthesis take place?
What is the equation for the process of
photosynthesis?
 What are the inputs for photosynthesis?
 What are the outputs for photosynthesis?
 Is a product considered an input or output? Explain.
 The reverse of photosynthesis
 Breaks down food (sugars) to make ATP to use for
cellular activities
 Sugar = long-term storage of energy, cannot be used right
away
 ATP = short-term, ready to use energy
 Reminder: takes place in the mitochondria
C6H12O6 + 6 O2 = 6 CO2 + 6 H2O + ATP
 Occurs in 3 Stages
1. Glycolysis- takes place in the cytoplasm of
the cell
2. Citric Acid Cycle (Krebs Cycle)- in the
mitochondria
3. ETC (Electron Transport Chain)- in the inner
membrane of the mitochondria
 Oxygen is not necessary for each stage:
 Glycolysis: anaerobic (no oxygen needed)
 Citric Acid Cycle and ETC: aerobic (need oxygen to go)
 If all 3 stages of cellular respiration occur, the total energy
created for the cell is: 38 ATP
 Occurs in the cytoplasm of the cell
 Consists of a series of chemical
reactions that breaks down glucose
(a 6-C compound - sugar) into 2 pyruvic acid molecules (a 3-C
compound)
 The 3-C pyruvic acid can move into
the mitochondria
 In aerobic conditions, pyruvic acid
Citric Acid Cycle Electron
Transport Chain
 In anaerobic conditions, pyruvic
acid fermentation
Inputs: Glucose
C6H12O6 + 2 ATP
Outputs: 2 pyruvic
acid + 4 ATP
 Occurs in the mitochondria of the
cell
 Cycle turns 2 times for every
molecule of sugar, so once per
pyruvic acid molecule
 Per 1 turn of the cycle:
 Inputs: Pyruvic acid (which has
been transformed to Acetyl CoA) +
oxygen + ADP
 Outputs: 2 CO2, 1 ATP, and
movement of e- to the inner
membrane of the mitochondria
 Occurs in the inner membrane of the
mitochondria
 Similar to the thylakoid membrane in the
cholorplast
 Basically, e- are used to create a charge on
one side of the membrane and then that
charge is used to attach a P to ADP to form
ATP as the e- move down the chain
 The final electron acceptor is oxygen
 If there is no oxygen present, the entire
chain stops!
 Inputs: e- gradient from citric acid cycle,
oxygen
 Outputs: 32 ATP, H2O
 Both the citric acid cycle and ETC need oxygen to occur
 When a cell needs energy but little or no O is available
for proper respiration, the cell will enter fermentation to
prevent cell death
 Doesn’t produce a lot of ATP
 Basically is a holding pattern for the cell
 2 kinds of Fermentation:
 Lactic Acid fermentation Many eukaryotic cells undergo this type of fermentation
 Lactic acid that is built up in muscle cells is transferred to
the liver, where it is converted back to pyruvic acid
 Alcoholic fermentation –
 Mostly done by by yeast and some bacteria
 CO2 is produced  we utalize this process to make beer,
cheese, bread, vinegar, wine and cider
Photosynthesis
Glucose (food) made
Respiration
Glucose broken down
Energy from sunlight makes
ATP  then stored in glucose
CO2 and H2O used
Stored energy in glucose
released as ATP
CO2 and H2O released
O2 released
Occurs in the presence of
chlorophyll- plants only
O2 used
Occurs in all living
organisms
Light needed
Occurs in chloroplasts
No light needed
Occurs in mitochondria