1. Anatomy and Physiology Cell Respiration Lecture 5
Marieb’s Human
Anatomy and Physiology
Marieb w Hoehn
Chapter 3
Mitochondria
Cell Respiration Lecture 5
44 slides; 84 min (w/o review)

2. Lecture Overview Mitochondria The Strategy of Cell Metabolism
Intro to Cellular Respiration
Glycolysis
TCA cycle
Electron Transport

3. A Closer Look at Mitochondria
Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001
(Impermeable to charged or polar molecules)
Mitochondria
membranous sacs with inner partitions
contain their own DNA
generate energy
Strategically placed in cell where ATP demand is high
Outer mitochondrial membrane is very porous – ions and other small mol up to about 5 KDa. Inner membrane imperm to ions/small molecules, but contains transporter proteins (carriers) for nucleotides, fuel molecules. FA oxidation and the TCA cycle occur in the matrix.
Concentration of enzymes in the matrix is so high that there is virtually no hydrating water. Enzyme-linked reactions and pathways are so crowded that normal rules of diffusion do not apply!

4. Overview of Cellular Metabolism
Metabolism – All the chemical reactions that occur in an organism
ETS
Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001

5. Overview of Catabolism
Figure from: Martini, Visual Anatomy & Physiology, Pearson, 2011

6. Overview of Glucose Breakdown
NAD+
NADH
NAD+
NADH
NAD+, FAD
NADH
FADH2
Figure from: Hole’s Human A&P, 12th edition, 2010

7. Overview of Cellular Respiration
Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001
Anaerobic
Cellular respiration
(aerobic)
ATP e-
*Most ATP from here e-
ETS (ETC)
+ e- e-
ATP
Structural – Functional Relationship - Inner membrane:
Contains Matrix where TCA cycle takes place
Has enzymes and molecules that allow Electron Transport System to be carried out

8. Source of e- for the Electron Transport Chain
Figure from: Hole’s Human A&P, 12th edition, 2010
Notice the flow of electrons to the Electron Transport Chain

9. Electron Transport Chain
NADH and FADH2 carry electrons to the ETC
ETC series of electron carriers located in cristae of mitochondria
energy from electrons transferred to ATP synthase
ATP synthase catalyzes the oxidative phosphorylation of ADP to ATP
water is formed
*Chemiosmosis
Figure from: Hole’s Human A&P, 12th edition, 2010

10. Oxidative Phosphorylation
Chemiosmosis, Chemiosmotic coupling, or Chemiosmotic phosphorylation
Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001

11. Anaerobic Glycolysis & Lactic Acid
During glycolysis, if O2 is not present in sufficient quantity, lactic acid is generated to keep glycolysis going so it continues to generate ATP (even without mitochondria)
Figure from: Hole’s Human A&P, 12th edition, 2010
NADH cannot enter the mitochondria directly. Its e- are transported via the glycerol phosphate shuttle (handed to FADH2) or the malate-aspartate shuttle (NADH is regenerated). NADH yields 2.5 ATP, while FADH2 yields 1.5 ATP.
NOTE what happens with and without O2 being available…

12. Review Cellular respiration
The metabolic processes by which ATP is produced
Major cellular steps:
Glycolysis
Cytoplasm
Anaerobic
TCA (Krebs, Citric Acid) cycle
Mitochondria
Aerobic
Electron Transport Chain
Most ATP produced here

13. Review Cell Nucleus The goal of metabolism Nuclear envelope (membrane)
provide the cell with energy (via catabolism; breakdown) and
materials for the manufacture of cellular components (via anabolism; synthesis, building up)
Cell Nucleus
Nuclear envelope (membrane)
porous double membrane
separates nucleoplasm from cytoplasm (*eukaryotes only)
Nucleoli – RNA organizing centers
Chromatin – combination of DNA and RNA