Download Cell Respiration

Mr. Kalin
Biology 10
Where do heterotrophs get
Energy?
 FOOD: building blocks for growth & life
 Food molecules contain chemical energy stored in their
chemical bonds
 Carbohydrates, Lipids, & Proteins

Energy stored in bonds depends on type of Food
Energy Measurement
 calories = amount of energy needed to raise 1 gram of
H2O 1 degree Celsius
 Calorie = 1,000 calories = 1 kilocalorie
 1 gram of glucose = 3811 calories
 1 gram of triglyceride = 8893 calories
 Carbs & Proteins store approx. 4,000 calories/gram
 Fats store approx. 9,000 calories/gram
Analyzing Data pg. 251
Most protein = Eggs, Most carbohydrate = Chocolate,
Most fat = Chocolate
2. 2 slices of Bacon = 5g(4Cal) + 6g(9Cal) = 74
Calories, 3 slices of turkey = 11g(4Cal) + 3g(4Cal) +
1g(9Cal) = 65 Calories
3. Chocolate = 3g(4Cal) + 23g(4Cal) + 13g(9Cal) = 221
Calories
1.
1.
221/300 = 44.2 minutes
Cell Respiration
 Cell’s role in making “E” for itself
 Cellular “E” = ATP
 Adenosine Tri-Phosphate
 We eat food (carbos, protein, & lipids) & the
mitochondria turn it into ATP
 Heterotrophs – must eat food to get energy (cannot
make their own)
Cell Respiration
 Occurs in the cytoplasm
and in the “Mighty”
Mitochondria
 Cell Respiration can occur
with or without Oxygen
(O2)
 Aerobic (yields more “E”)
 Anaerobic (fermentation =
less “E”)
 C6H12O6 + 6O2  6CO2 +
6H2O + “E” (ATP)
Where does the “E” come from?
 C6H12O6 – the bonds
between the
molecules are where
the energy is stored!
 Cell Respiration is a
step-by-step process
that breaks the bonds
of the glucose and
converts the “E” to
ATP
Structural Formula of Glucose
3 Stages of Cell Respiration
 Glycolysis
 Occurs in cytoplasm
 Splits the glucose in 2
 Yields 2 ATP
 Kreb’s Cycle
 Breaks glucose completely
apart
 Electron Carriers store bond
“E” and take it to E.T.C.
 Yields 2 ATP
 Electron Transport Chain
 Takes bond “E” and makes
MAJOR amount of ATP
 Yields 34 ATP!!!
Glycolysis
 Glyco – sugar
 Lysis – breaking
 2 ATP required to begin




process
4 ATP are produced = net
gain of 2 ATP
Glucose (6C) is broken
into 2 pyruvic acids (3C)
2NAD+ + 2NADH (4 e)
Fast – can produce
thousands of ATP & does
not require O2
Kreb’s Cycle
 Occurs in the matrix (center) of mitochondria
 Pyruvic Acid is broken down through a series of
chemical rx
 Extracts electrons and some energy and releases CO2
 Begins by…
 1 C molecule is removed from Pyruvic Acid (CO2),
coenzyme A is added  Acetyl CoA
 Joins with 4 C molecule  Citric Acid
Kreb’s Cycle Continued
 Citirc Acid is then broken down into a 4 C molecule
 2 CO2 molecules are released
 1 ATP is produced
 8 Electrons are transferred to electron carriers
 Because glycolysis produces 2 pyruvic acid molecules
from each glucose molecule, the Kreb’s Cycle “turns”
twice (double the output above)
Electron Transport Chain
 Occurs in the membrane space of mitochondria
 Products from the Kreb’s and glycolysis feed this cycle
 Only works in the presence of O2
 This chain uses the energy from the “high energy”
electrons to turn ADP  ATP
ETC Continued (Electron Transport)
 NADH & FADH2 dump their electrons off within the
membrane of the mitochondria
 The ETC contains a series of electron carriers that pass
the electrons down to an enzyme that uses their
energy to form ATP
 For every 2 high energy electron that pass down the
chain, H+ ions are transferred to the intermembrane
space, making it more + compared to the matrix
ETC Cont. (ATP Production)
 Chemiosmosis – process by which a cell produces ATP
 The H+ ions use the established concentration
gradient to move through the enzyme, ATP synthase,
an O atom accepts 2 H+ ions and 2 electrons  H2O
 As they move down their gradient, ATP synthase spins,
each spin grabs an ADP and joins it with a P to make
ATP
 Each pair of electrons can generate 3 ATP
Cell Respiration Totals
 All Totals per Glucose (C6H12O6) molecule
 Glycolysis
 2 ATP
 Kreb’s Cycle
 2 ATP
 Electron Transport Chain
 32-34 ATP
What happens when NO O2 is
present?
 In Animals?
 Lactic Acid Fermentation
 Muscle Cramps
 Why does this happen?
 NADH builds up but
there is no where for the
electrons to go!
 NAD+ needs to be
recycled or it will run out
 Lactate removes the
electrons from NADH 
NAD+
Energy & Exercise
 3 sources of muscle
energy
 ATP stored in muscles
 seconds
 ATP made from lactic
acid fermentation

Up to 90 seconds
 ATP made from cellular
respiration

Any activity above 90
seconds
Prokaryotic Energy Production
 In Smaller Organisms
(bacteria)?
 Fermentation
 Milk, Yogurt, Cheese
 Alcoholic Fermentation
 Yeasts and a few other
organisms
 Produces ethanol & CO2
 Makes spirits & bread
Alcoholic Fermentation