Cellular Respiration

Respiration
• Respiration – the
biochemical process that
makes ATP from
glucose
• Occurs in both
autotrophs and
heterotrophs.
AND

Respiration
• There are two types of respiration,
AEROBIC and ANAEROBIC.
• Aerobic respiration requires OXYGEN to
release energy.
• The chemical equation for aerobic
respiration is:
C6H1206 + 6O2
Glucose
Oxygen
 6H2O + 6CO2 + 36 ATP
Water
Carbon Dioxide
Energy

Respiration
• Anaerobic respiration DOES NOT
REQUIRE OXYGEN. (Also called
FERMENTATION)
• Both aerobic and anaerobic respiration
begin with the same process, glycolysis.

Glycolysis
• Occurs in CYTOPLASM
• Means “split the sugar,”
• The chemical equation for glycolysis is:
C6H12O6 + 2 ATP  2 Pyruvic acid + 4 ATP

Glycolysis
1. Glucose molecules are broken down
into 2 pyruvic acid (pyruvate)
molecules
2. Two ATP molecules are used and four
ATP molecules are created resulting in a
net gain of two ATP.
3. Following glycolysis, the pyruvic acid
molecules can follow two paths: aerobic
respiration or anaerobic respiration.

Glycolysis
2
Glucose
Glycolysis

Aerobic Respiration
• Occurs in the MITOCHONDRIA
1. Pyruvic acid molecules are converted
to Acetyl-CoA molecules.
2. Acetyl-CoA broken down into H+, CO2,
and ATP
•
Krebs Cycle
3. The H+ ions bond to carrier molecules,
NAD+ and FAD to make NADH and
FADH2.

Aerobic Respiration
4. NADH and FADH2 go through a series of step
reactions – the electron transport chain – to
produce ATP.

Aerobic Respiration
• Each cycle produces 10 NADH
molecules, 2 FADH2 molecules and 2
ATP.
1 NADH = 3 ATP
1 FADH2 = 2 ATP
• The end product of aerobic respiration is
the production of 36 ATP MOLECULES.

Aerobic Respiration
Glucose
Glucose
2
36
Glycolysis
Glycolysis
Krebs
cycle
Electron
transport

Anaerobic Respiration
• Occurs in the CYTOPLASM.
• Occurs in the absence of oxygen

Anaerobic Respiration
• Lactic acid Fermentation- converts pyruvic
acid to lactic acid and CO2
– Lactic acid can build up in muscles when they run out
of oxygen and causes muscle soreness
• Alcoholic fermentation- converts pyruvic acid
to ethanol and CO2
– Process used to make wine, beer, cheese, and bread
• Both processes result in the production of only 2
ATP MOLECULES.

Factors Affecting Respiration:
• ATP concentration - the more ATP
molecules available, the slower the rate of
respiration.

Anaerobic Respiration
2
36
Glucose
Glycolysis
Krebs
cycle
Fermentation
(without oxygen)
Electron
transport
Alcohol or
lactic acid