The Mitochondria!

Review of Membranes…

A

BC

D

E

F

G

AB C

F

E

D

G

Outer membrane with porins

Outer compartment (cytosol)

Inner membrane with Cristae

MatrixEnzymes! Hexokinase (adds P to ADP) and Dehydrogenases (catalyze redox reactions)

Which of the following can get into the outer membrane?

MITOCHONDRIA

Mitochondria • Double membrane

– outer membrane– inner membrane

• highly folded cristae• enzymes & transport

proteins– intermembrane space

• fluid-filled space between membranes

intermembranespace inner

membrane

outermembrane

matrixcristae

Mitochondria — Structure• Double membrane energy harvesting organelle

– smooth outer membrane– highly folded inner membrane

• cristae– intermembrane space

• fluid-filled space between membranes– matrix

• inner fluid-filled space– DNA, ribosomes– enzymes

• free in matrix & membrane-bound

mitochondrialDNA

What cells would have a lot of mitochondria?

Mitochondria – Function

What does this tell us about the evolution of eukaryotes?

Endosymbiosis!

Dividing mitochondriaWho else divides like that?

Advantage of highly folded inner membrane?More surface area for membrane-bound enzymes & permeases

Membrane-bound proteinsEnzymes & permeases

bacteria!

The Real Deal

The Real Deal

Enzymes on the Outside

• Hexokinases- adds P onto ADP

• Dehydrogenases- catalyze REDOX– Transfers electrons (H) to an acceptor NAD or FAD

• FAD and NAD are electron carriers