CHAPTER 9

CELLULAR RESPRIRATION:

HARVESTING CHEMICAL ENERGY

http://www.johnkyrk.com/mitochondrion.html

Energy flow and chemical recycling in ecosystems

NADH2

orNADH- + H+

Almost 40% of the energy in glucose is converted to ATP

Each glucose uses 2 ATP then produces 4 ATP for a net of 2 ATP it also reduces 2 NAD+’s to form 2 NADH2; 2-3C pyruvates are also formed

Substrate-level phosphorylation –the phosphate group is at a higher energy level on the phosphoenolpyruvate than it is on ATP so it can be directly transferred

FormingAcetyl-CoA

Occurs inside the matrix

For the 2 pyruvates from a glucose, it produces 2 NADH2, releases 2 CO2 and 2 acetyl groups each attached to a Coenzyme A

From each Acetyl-CoA 3 NADH2 X2 1 FADH2 for the 1 ATP 2 acetyl 2 CO2 groups

6 NADH2

2 FADH2

2 ATP 4 CO2

ADP

phosphate

active site

Lower potential energy

Higherelectronegativity

Electrons from 1 NADH2 cause transport of 6H+’s that produce 3 ATP

1 FADH2 only 4H+’sonly 2 ATP

H+ + OH- =H2O

2e- + 2H+’s + O H2O

Inner membrane-cristae

Cytochrome/proton pump/transport protein

OH- OH- 2H+ OH-

OH-

OH- OH- OH- OH-

ATP syntaseATP synthase

Matrix

Intermembrane

space cytochrome

Path of electrons

NADH22e-

2H+NAD

H+ H+

H+ H+

H+ H+

FADH2 2e-

FAD

H+ H+ H+ H+

2e-

Chemiosmosis

Proton Motive Force

cytochromes

ADP P

ATPIn the matrix there is alwaysa surplus of free

OH- so any free H+ will immediately combine with them and form water

Each glucose uses 2 ATP then produces 4 ATP for a net of 2 ATP it also reduces 2 NAD+’s to form 2 NADH2; 2-3C pyruvates are also formed

Lower potential energy

Higherelectronegativity

Electrons from 1 NADH2 cause transport of 6H+’s that produce 3 ATP

1 FADH2 only 4H+’sonly 2 ATP

H+ + OH- =H2O

2e- + 2H+’s + O H2O

Inner membrane-cristae

Cytochrome/proton pump/transport protein

OH- OH- 2H+ OH-

OH-

OH- OH- OH- OH-

ATP syntaseATP synthase

Matrix

Intermembrane

space cytochrome

Path of electrons

NADH22e-

2H+NAD

H+ H+

H+ H+

H+ H+

FADH2 2e-

FAD

H+ H+ H+ H+

2e-

Chemiosmosis

Proton Motive Force

cytochromes

ADP P

ATP

• http://www.johnkyrk.com/mitochondrion.swf