Download Cellular Respiration Food to Energy Food to Energy Calorie Questions

1/9/2017
Food to Energy
Cellular Respiration
Chapter 9
Food to Energy
• BIG PIECES of food are
digested into tiny
nutrients
• Nutrients are absorbed
into the bloodstream in
the small intestine
Calorie
• Calorie = Measure of energy present in food
• Glucose is the basic fuel of
the body
• One calorie = amount of heat energy needed
to raise the temperature of 1 g of water 1oC
• Absorbed through villi into
the blood stream, where it
goes as “food” to ALL body
cells
Calorie
•
Calorie (with a capital
C) is actually a
kilocalorie (kcal)
•
1 Calorie = 1000
calories
•
Food calories are kcal;
they measure the heat
energy in food.
Questions
1. If you are eating 1,200 Calories a day, how
many calories are you eating?
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What is cellular respiration?
Cellular respiration is the process that releases
energy by breaking down glucose and other food
molecules in the presence of oxygen. The equation
for cellular respiration is:
Where is the energy generated?
The cells of all organisms, except bacteria
(prokaryotes), generate energy in
mitochondria.
6O2 + C6H12O6  6CO2 + 6H2O + Energy
Oxygen + glucose  carbon dioxide + water + energy
There are 2 types of cellular respiration:
1. Aerobic: needs O2; produces 36 ATP’s for
each glucose molecule.
1. Anaerobic: does NOT need O2, produces 2
ATP’s for each glucose molecule.
OVERALL EQUATION for
Aerobic Respiration:
C6H12O6 + 6O2  6CO2 + 6H2O + ATP
Sugar + Oxygen
 Carbon + Water + Energy
Dioxide
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Overview
Questions
1. Where does cellular respiration take place?
2. What is the main difference between aerobic
and anaerobic respiration?
3. In aerobic respiration, what do you begin
with? From where do these come?
Aerobic Respiration has 3 stages. One occurs in the
cytoplasm and two occur in the matrix of the
Mitochrondria.
1. Glycolysis
2. Kreb’s Cycle
3. Electron Transport Chain
Step 1: Glycolysis
• Occurs in the cytoplasm
• Breaks one molecule of glucose in half
• Produces 2 molecules of pyruvic acid
(pyruvate)
• Requires 2 ATP to get started. During the
process, 4 ATP are made. Overall, you GAIN 2
ATP.
Glycolysis
Glycolysis
Energy yield is small
Happens fast
Does not require oxygen
Produces 2 ATP (overall), 2 NADH, and 2
pyruvic acid
• Limited by NAD+ (If all of the NAD+ is NADH,
•
•
•
•
glycolysis stops, ATP production stops)
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Questions
1. Where does glycolysis take place?
2. How much energy is yielded during
glycolysis?
3. Glycolysis breaks glucose into TWO
________.
Step 2: Kreb’s Cycle
• If oxygen is present (aerobic), Kreb’s Cycle is
next
• Also known as Citric Acid Cycle
• Occurs in the mitochondria
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Kreb’s Cycle
• During the cycle:
– Pyruvic acid is broken down into CO2
– Electrons are transferred to energy carriers
– Produces: CO2, 3 NADH, 1 FADH2, and 1 ATP (x2
because 2 pyruvic acids)
Questions
1. Where does Kreb’s cycle take place?
2. What do you begin the Kreb’s cycle with?
3. What are the products of the Kreb’s cycle?
Step 3: Electron Transport Chain
• High energy electrons from NADH and FADH2
go through electron transport chain.
• Energy is used to transport H+ ions into the
mitochondria space
• H+ ions go through ATP synthase, so ADP is
converted into ATP
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Electron Transport Chain
Electron Transport Chain
• Produces:
– Water is made (H+ and e- combine with
oxygen). [Oxygen is the final electron
acceptor—that’s why we need oxygen!]
– 32 ATP
Aerobic Respiration Totals
•
•
•
•
Glycolysis = 2 ATP
Kreb’s Cycle = 2 ATP
Electron Transport Chain = 34 ATP (32-34)
Total = 38 ATP (36-38)
Questions
1. Write the equation for respiration. Label
where each piece comes from.
Video: ATP + Respiration - Crash Course
Anaerobic Respiration
• Occurs if oxygen is NOT present.
• Glycolysis still occurs first
• Followed by fermentation
Two types of fermentation:
a. Alcoholic Fermentation
b. Lactic Acid Fermentation
(Both free up NAD+, but both leave most of the
energy in the final product)
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Alcoholic Fermentation
Alcoholic Fermentation
• Yeast and other microorganisms go through
this
• Produces CO2, alcohol, and NAD+
• Used to make bread and alcoholic beverages
Lactic Acid Fermentation
Lactic Acid Fermentation
• Produces lactic acid and NAD+
• Lactic acid is produced by muscles during
rapid exercise when the body cannot supply
enough O2
• Build up of lactic acid causes painful, burning
sensation.
Questions
• What are the two types of fermentation?
• When does fermentation occur?
• Compare the energy produced from
respiration with the energy produced from
fermentation.
The Race
• 1st – Your body uses the stored ATP (only good
for a few seconds of energy)
• 2nd – Your body produces ATP through lactic
acid fermentation (lasts up to 90 seconds)
• 3rd –Your body must go through cellular
respiration for anything longer than 90
seconds.
Video: Bozeman Cellular Respiration
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Photosynthesis & Respiration Compared
Questions
• Compare the reactants, products, and
equations of photosynthesis and respiration.
Function
Photosynthesis
Respiration
Energy storage
Energy release
Location
Reactants
Products
Equation
Photosynthesis & Respiration Compared
Photosynthesis & Respiration Compared
Photosynthesis
Respiration
Photosynthesis
Respiration
Function
Energy storage
Energy release
Function
Energy storage
Energy release
Location
Chloroplasts
Mitochondria
Location
Chloroplasts
Mitochondria
Reactants
Reactants
CO2 and H2O
C6H12O6 and O2
Products
Products
Equation
Equation
Photosynthesis & Respiration Compared
Photosynthesis & Respiration Compared
Photosynthesis
Respiration
Photosynthesis
Respiration
Function
Energy storage
Energy release
Function
Energy storage
Energy release
Location
Chloroplasts
Mitochondria
Location
Chloroplasts
Mitochondria
Reactants
CO2 and H2O
C6H12O6 and O2
Reactants
CO2 and H2O
C6H12O6 and O2
Products
C6H12O6 and O2
CO2 and H2O
Products
C6H12O6 and O2
CO2 and H2O
Equation
6 CO2 + 6 H2O 
C6H12O6 + 6 O2
C6H12O6 + 6 O2
6 CO2 + 6 H2O
Equation
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