Cellular Respiration
What is Cellular
Respiration?
 The process of converting food energy into
ATP energy
 C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + 36 ATP
Why do plants need both
chloroplasts and
mitochondria?
 Chloroplasts use
energy from the sun
to make glucose
 Mitochondria convert
glucose to ATP—the
energy currency of
the cell
What is ATP?
 Adenosine Triphosphate
 5-Carbon sugar (Ribose)
 Nitrogenous base (Adenine)
 3 Phosphate groups
 Energy currency of the cell
 The chemical bonds that link
the phosphate groups
together are high energy
bonds
 When a phosphate group is
removed to form ADP and P,
small packets of energy are
released
So what?
 Energy is stored in these bonds.
 So?
 The breaking of the chemical bond
releases the energy
ATP + H2O→ ADP + P + ENERGY
How is ATP used?
 As ATP is broken down, it
gives off usable energy to
power chemical work and
gives off some nonusable
energy as heat.
 Synthesizing molecules for
growth and reproduction
 Transport work – active
transport, endocytosis, and
exocytosis
 Mechanical work – muscle
contraction, cilia and flagella
movement, organelle
movement
Cellular Respiration
 The process by which mitochondria
break down glucose to make ATP
 In order for our bodies to use the energy,
the food must be broken down into a
usable form
 What is the usable form of energy?
 What type of process breaks down
molecules?
Cellular Respiration
Cellular Energy
•The Stages of Cellular Respiration Cellular
respiration has two stages.
•Glycolysis The first stage of cellular respiration is
called glycolysis.
•Aerobic and Anaerobic Respiration The second
stage of cellular respiration is either aerobic respiration
(in the presence of oxygen) or anaerobic respiration (in
the absence of oxygen). A large amount of ATP is made
during aerobic respiration. NAD+ is recycled during
the anaerobic process of fermentation.
Cellular Respiration
Stage One: Breakdown of Glucose
•Glycolysis Glucose is
broken down to
pyruvate during
glycolysis, making
some ATP.
Cellular Respiration
Stage Two: Production of ATP
•Krebs Cycle The Krebs
cycle is a series of
reactions that produce
energy-storing molecules
during aerobic respiration.
•Electron Transport
Chain During aerobic
respiration, large amounts
of ATP are made in an
electron transport chain.
Cellular Respiration
Fermentation in the Absence of Oxygen
•Fermentation When oxygen
is not present, fermentation
follows glycolysis,
regenerating NAD+ needed
for glycolysis to continue.
•Lactic Acid Fermentation
In lactic acid fermentation,
pyruvate is converted to
lactate.
Cellular Respiration
 Cellular Respiration is a metabolic
process like burning fuel
 Releases much of the energy in food to
make ATP
 This ATP provides cells with the energy
they need to carry out the activities of life.
 C6H12O6+O2
CO2 + H2O + ATP
Review
 When oxygen is present most the ATP
made in cellular respiration is produced
by:
A. aerobic respiration
B. Glycolysis
C. alcoholic fermentation
D. Lactic acid fermentation.