Cellular Respiration

1
Cellular Respiration
The Overview
2
Review

• Two ways that organisms obtain food
• Autotrophs
• Self-feeders
• Plants and other organisms that make their own
  food by the process of photosynthesis.
• Heterotrophs
• Other-feeders
• Humans and other animals that cannot make their
  own food. Require food that is already made.

3
Review

• The sun is the main source of energy for the
  planet.
• Plants and photosynthetic organisms are the only
  ones that can actually use this energy.
• Photosynthetic organisms convert the energy from
  the sun (light energy) into chemical energy (they
  form ATP)
• Photosynthetic organisms make this energy
  available to the rest of the organisms (and for
  themselves) by making glucose (the fuel for life)

4
Remember the Carbon Cycle?
5
Basically

• Carbon dioxide removed from the atmosphere by
  photosynthesis
• 6CO2 6H2O C6H12O6 6O2
• Carbon dioxide is returned to the atmosphere by
  cellular respiration, decomposition and
  combustion (burning)
• C6H12O6 6O2 6CO2 6H2O

6
(No Transcript)
7
What is cellular respiration?

• The chemical process by which food
• (i.e. glucose) is broken down by the body's
  cells to harvest energy, in the form of ATP.

8
What is cellular respiration? (2)

• Both plants and animals perform cellular
  respiration
• Produces CO2 and H2O as waste products

9
There are three main stages of cellular
respiration

• Stage 1 Glycolysis
• Stage 2 Krebs Cycle
• Stage 3 the Electron Transport Chain
  (ETC).

10
Where does Cellular Respiration occur?

• There are two locations for Cellular respiration.
• Stage 1 (Glycolysis) occurs in the cytoplasm of
  cell
• Stage 2 and 3 (Krebs Cycle and ETC) occur in the
  mitochondria

11
Anaerobic (without oxygen) Respiration

• Glycolysis
• Occurs in the cytoplasm of animal cells and yeast
• Produces energy in the form of ATP
• Only makes 2 ATP each time (not very efficient)

12
In Yeast (Alcoholic Fermentation)

• Glucose ? 2 pyruvic acid 2ATP.
• pyruvic acid ? alcohol
• Yeast does not have the enzymes to break down
  alcohol further
• So the release of energy stops.

13
In Animal Muscle tissue (Lactic Acid
Fermentation)

• Glucose ? 2 pyruvic acid 2ATP
• Pyruvic acid ? lactic acid and in the absence of
  oxygen(anaerobic) cannot be broken down.
• Lactic acid can build up in your muscles and you
  feel pain and muscle cramps (your body is
  telling you that you need oxygen!)

14
Aerobic (with oxygen) Respiration (Krebs Cycle
and Electron Transport Chain)

• Occurs in the mitochondria
• Requires oxygen
• Glucose is completely broken down to CO2 and H2O
• Produces 34 more molecules of ATP for a total of
  36 (thats a lot of energy!)

15
The Overall Equation for Cellular Respiration

• A common fuel molecule for cellular respiration
  is glucose

Glucose
Oxygen
Carbon dioxide
Water
and Energy
16
Cellular Respiration Requires Oxygen!!

• Cellular respiration is aerobic
• Aerobic reactions that need oxygen to happen or
  happen when oxygen is present

17
The Relationship Between Cellular Respiration and
Breathing

• Cellular respiration and breathing are closely
  related

• Cellular respiration requires a cell to exchange
  gases with its surroundings (O2 in and CO2 out)
• Breathing exchanges these gases between the blood
  and outside air in the lungs

18
(No Transcript)
19
Remember!

• Without oxygen, the pyruvic acid in your muscles
  will be converted to lactic acid.
• A cool down is needed to replenish your muscles
  with oxygen so aerobic respiration can take
  place.

20
Apply what you have learned

• Use your notes to fill in the graphic organizer
  for Cellular Respiration (wordbank on back)
• Answer the questions on cellular respiration
  (also on the back)
• Do the assignment comparing photosynthesis and
  cellular respiration.