1. Cellular Respiration

2. Mitochondria are the
“power houses” of the
cell.
They produce
energy through
metabolic activities
called cellular
respiration.
This energy comes
from ATP.
(Adenosine
Triphosphate)

3. Light energy from the sun
Living plant and animal matter

4. Cellular respiration must be controlled by enzymes, rather
than fire, to release energy in small steps, so the body won’t be damaged.

5. This is the basic concept
of cellular respiration:
Sunlight
Photosynthesis
Plant gets eaten
Respiration
Energy!
Sweat!

6. There are 2 kinds of cellular respiration:
Aerobic Respiration: this is respiration, which requires
oxygen. Humans and other animals carry on this type of
respiration. Some texts also refer to this as metabolism.
Fermentation: This is anaerobic respiration, meaning it
does not require Oxygen. Yeast and some bacteria carry
on anaerobic respiration, also called fermentation.
Yeast cells

7. There are several reactions or pathways involved in cellular
respiration: Glycolysis, The Kreb’s Cycle, and The Electron
Transport system, for example. The mitochondria are
required to bring about cellular Respiration. Let’s look at the
mitochondria’s structure:

8. Here is a more simplified version of the inside structure of
the mitochondria:

9. First, we will learn about Aerobic Respiration.
As mentioned before, this requires oxygen.
The pathways involved in Aerobic Respiration
are:
(Reaction – where it takes place.)
Glycolysis – takes place outside the mitochondria.
The Transition Reaction – inside the mitochondria.
The Kreb’s Cycle – inside the mitochondria.
The Electron Transport System – in the cristae
of the mitochondria.

10. Glycolysis – this is the breakdown of glucose into
two molecules of pyruvate.*
*Pyruvate is an important metabolite** in cellular respiration.
**A metabolite is an intermediate chemical in a reaction.

11. The Transition Reaction – Pyruvate is oxidized to an
acetyl group, and CO2 is removed.

12. The Kreb’s Cycle – Takes place in the matrix of the mitochondria
The Kreb’s Cycle – Takes place in the matrix of the mitochondria. It is a series of oxidation reactions that release CO2 and produce ATP. The Kreb’s Cycle immediately accounts for 2 ATPs produced per glucose molecule.

13. The Electron Transport System - a series of carriers that
accept the electrons removed from glucose and pass them from one
carrier to the next until they are finally accepted by oxygen. As the
electrons move from a higher to a lower energy state, energy is released
and stored in ATP.

14. *What is ATP? Why is it so important?
ATP is a chemical called Adenosine Triphosphate.
It is important because…
It stores a lot of bond energy in the bond between the 2nd
and 3rd phosphates!

15. Total
Energy
Yield:

16. Overview of Cellular Respiration:

17. Fermentation is cellular respiration without oxygen.
It consists of glycolysis followed by the reduction of pyruvate
By NADH to either lactate or alcohol and CO2. The pathway
operates anaerobically, because after NADH transfers its
electrons to pyruvate, it is free to return and pick up more
electrons during the earlier reactions of glycolysis.
Who needs oxygen?

18. This is a simplified version of alcohol fermentation:

19. Here is a simplified version of lactic acid fermentation:

20. Fermentation is not as efficient as Aerobic Cellular Respiration.
It only produces two ATPs per glucose molecule. Lactic acid is
also toxic. When it builds up in the body, it changes the pH of
blood, causing muscle fatigue and soreness.
However, fermentation creates quick energy release for times
when we do strenuous exercise. Fermentation provides a way
for our bodies to produce ATP even though oxygen is at short
supply.

21. Industrially, fermentation is important for production of
alcoholic beverages, as well as bread making. The
fermentation ability of yeast plays an important role in both
of these processes.

22. The many reactions of Cellular Respiration are all brought to you by:
THE MIGHTY MITOCHONDRIA!
THE END