Download Cellular Respiration

Cellular
Respiration
Objective 18: Analyze photosynthesis and cellular respiration in terms
of how energy is stored, released, and transferred within and between
these systems
Cellular Respiration
•
Occurs within ALL living cells
•
Chemical bonds are broken in glucose releasing energy (ATP) to be used
by cells.
•
Aerobic Respiration:
 C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + energy
 oxygen needed
 Yields 36 ATP
 Starts in cytoplasm and ends in mitochondria
Photosynthesis to Cell Resp.
The products of
photosynthesis
are the
reactants of
cellular
respiration!
Mitochondria
Types of Cellular Respiration
•
Aerobic
 “With oxygen”
 Uses oxygen to produce ATP
 Produces more ATP than anaerobic respiration
•
Anaerobic
“Without oxygen”
Produces ATP in the absence of oxygen
Not as efficient as aerobic respiration
Alcoholic fermentation  yeast converts glucose into CO2
and ethanol
 Lactic acid fermentation occurs in muscle cells when
oxygen is not available and produced CO2 and lactic acid




Aerobic Respiration Flowchart
Cellular Respiration
Glucose
(C6H1206)
+
Oxygen
(02)
Glycolysis
Krebs
Cycle
Electron
Transport
Chain
Carbon
Dioxide
(CO2)
+
Water
(H2O)
+
ATP
Aerobic Respiration
Step 1: Glycolysis
Occurs in the cytoplasm
Glucose (C6H12O6) is split into two
molecules of pyruvic acid
Yields 2 ATP molecules and 2 NADH
(another energy molecule)
Aerobic Respiration
Step 2: Krebs Cycle
Occurs in matrix of the mitochondria; pyruvic acid is converted to CO 2
2 NADH (energy molecules), 2ATP, and
2 FADH2 (energy molecules) are also
formed
Aerobic Respiration
•
Step 3: Electron Transport Phosphorylation:
•
Occurs in mitochondria; uses the high energy electrons captured in the Krebs
Cycle (in NADH and FADH2) to form ATP and water.
Every time 2 high-energy electrons go down
the electron transport chain, their energy is
used to transport H+ ions across the inner
membrane of a mitochondrian
Step 3: Electron Transport Phosphorylation:
(continued)
 H+ ions build up in the inner membrane space
setting up a concentration and an electrical
gradient. As H+ ions rush back through the
membrane, enough energy is created to cause
ADP to combine with P to form ATP
 This step produces 32 ATP for a net yield of 36
 Water is also produced as a product
Aerobic Respiration Flowchart
Cellular Respiration
Glucose
(C6H1206)
+
Oxygen
(02)
Glycolysis
Krebs
Cycle
Electron
Transport
Chain
Carbon
Dioxide
(CO2)
+
Water
(H2O)
+
ATP
Aerobic Respiration Summary
Anaerobic Respiration
Occurs in the absence of oxygen
Yields only 2 ATP
Happens in cytoplasm
The first step is glycolysis. The pyruvate is
converted to ethanol or lactic acid.
Alcoholic Fermentation
•
Occurs in yeast
•
Step 1: Glycolysis
 Glucose is converted to pyruvate
 Net 2 ATP
•
Step 2: Ethanol Formation
 Pyruvate is converted to ethanol
Lactic Acid Fermentation
• Occurs
in
bacteria and
animals
•
C6H12O6
2
Step 1: Glycolysis
 Glucose is converted to
pyruvate
 Net 2 ATP
•
glycolysis
Step 2: Lactate formation
 Pyruvate is converted to
lactic acid
ATP
energy input
2 NAD+
2 ADP
2
4
NADH
ATP
energy output
2 pyruvate
2 ATP net
lactate
formation
electrons, hydrogen
from NADH
2 lactate