Cellular Respiration
Mr. Graham
Harvesting Energy from Food!

Cellular respiration
is a chemical
reaction that uses
oxygen to convert
the chemical
energy stored in
organic molecules
into ATP.
ATP



Adenosine
triphosphate – it is the
source of energy used
for most cellular work.
When we take in food,
ADP is converted to
ATP in the process of
cellular respiration.
When our cells use
this energy, ATP is
converted to ADP.
What can ATP be used for?
 ATP
can be used for:
– Moving a Muscle Protein
– Building Large Molecules
– Active Transport
Synthesis and Active Transport
Aerobic Cellular Respiration
Aerobic = with oxygen
 Occurs in the mitochondria
 The use of oxygen releases more energy per
glucose molecule than anaerobic = without
oxygen
 Uses oxygen but releases carbon dioxide and
water
SUMMARY EQUATION:

Cellular Respiration
 Cellular
Respiration is an aerobic
process, meaning that it requires
oxygen.
Both plant and animal cells carry out the final
stages of cellular respiration in the
mitochondria.
Intermembrane
Mitochondrion
space
Outer membrane
Animal Cells
Plant Cells
Inner
membrane
Matrix
Cellular Respiration
 There
are three parts of cellular
respiration. They are glycolysis,
krebs cycle, and electron tranport
system.
STAGES OF CELLULAR
RESPIRATION

Respiration occurs in three main stages
High-energy electrons
carried by NADH
GLYCOLYSIS
Cytoplasmic
fluid
KREBS
CYCLE
ELECTRON
TRANSPORT CHAIN
Mitochondrion
Cellular Respiration
Glycolysis
2ATP
Produced
Cytoplasm
Krebs Cycle
2ATP
Produced
Mitochondria
Electron
Transport
System
34 ATP
Mitochondria
Fermentation is an anaerobic
alternative to aerobic respiration
Process operates by means of chemical
reactions catalyzed by enzymes in
cytoplasm of cell
 Primary mode of energy production for
some bacteria and fungi (yeast)
 use glycolysis alone to produce small
amounts of ATP
 Important in production of foods such as
cheese, buttermilk, yogurt, alcohol,
(wine/beer) and bread
 2 types: 1. alcohol & 2. lactic acid

Fermentation



Some organisms can
ferment glucose to
make energy. This is
a form of anaerobic
respiration.
The products of
fermentation depend
upon the type of
organism. Some
yeast ferment sugar
and make alcohol as a
by product.
What is a problem
with fermentation?
Lactic Acid Fermentation
 When
oxygen levels decrease, your
muscles make energy using lactic
acid fermentation. The by product of
this fermentation is 2ATP and lactic
acid.
How do microbes help us?
 Bacteria
and fungi are used to
tranform milk into yogurt and
cheese. The sharpness or sour flavor
of yogurt is due to lactic acid.
Photosynthesis
Energy and Life



Plants and some other
types of organism are
able to use light
energy from the sun
to produce food.
Autotrophs –
organisms that are
able to synthesize
their own food.
Heterotrophs – obtain
energy by consuming
other organisms.
Photosynthesis
 Plants
use the energy of sunlight to
convert water and carbon dioxide
into oxygen and high energy
carbohydrates.
Structure of a Leaf




Xylem – carries water
from the roots to
leaves.
Phloem – carries food
(glucose) from leaves
to the roots.
Stomata – tiny holes
in bottom of the leaf
that function in gas
exchange.
Guard cells – control
the opening and
closing of guard cells.
Light and Pigments
 In
addition to water and carbon
dioxide, photosynthesis requires light
and chlorophyll, a molecule found in
chloroplasts.
 Plants gather the suns energy with
light absorbing molecules called
pigments (chlorophyll).
Why are leafs green?

There are two
types of
chlorophyll,
chlorophyll a and
chlorophyll b.
These pigments
absorb red and
blue light, and
reflect green.
Other Pigments




Carotenoids, which produce yellow, orange, and brown
colors in such things as corn, carrots, and daffodils.
Anthocyanins, which give color to such familiar things as
cranberries, red apples, concord grapes, blueberries,
cherries, strawberries, and plums.
Why do leaves change colors in the autumn?
During the growing season, chlorophyll is continually being
produced and broken down and leaves appear green. As
night length increases in the autumn, chlorophyll
production slows down and then stops and eventually all
the chlorophyll is destroyed. The carotenoids and
anthocyanins that are present in the leaf are then
unmasked and show their colors.
Paper Chromotography

Paper
chromatography
is a technique for
separating and
identifying
mixtures that are
or can be colored,
especially pigments
found in plants.
Rate of Photosynthesis
 Amount
of Water available
 Temperature
 Light Intensity
 Amount of CO2 present.
Comparing photosynthesis and
Cellular Respiration