Kreb's Cycle / Electron Transport System

Kreb’s Cycle

a 7-reaction cycle occurring in the mitochondria

How many cycles are ran per 1 molecule of glucose?

2 cycles/1 molecule of glucose

(1) Kreb’s Cycle

Acetyl CoA → Oxaloacetate = Citrate

Last product in the Citric Acid Cycle

Oxaloacetate

(2) Kreb’s Cycle

Citrate → Isocitrate

(2) Enzyme

Isomerase

(3) Kreb’s Cycle

* Isocitrate (6 C) → alpha-ketoglutarate (5 C)
* NAD → NADH
* CO2 eliminated

(3) Enzyme

* Isocitrate deHase

(4) Kreb’s Cycle

* alpha-ketoglutarate (5 C) → Succinate (4 C)
* NAD → NADH
* CO2 eliminated

(4) Enzyme

alpha-ketoglutarate deHase

(5) Kreb’s Cycle

* Succinate (4 C) → Fumarate (4 C)
* FAD → FADH2

(5) Enzyme

Succinate deHase

(6) Kreb’s Cycle

* Fumarate (4 C) → Malate (4 C)

(6) Enzyme

Isomerase

(7) Kreb’s Cycle

* Malate (4 C) → Oxaloacetate (4 C)
* NAD → NADH

(7) Enzyme

Malate deHase

Electron Transport System

taking the reduced forms of co-enzymes (FAD and NAD) and putting them through series of reactions occurring in the mitochondria in an effort to make ATP

How many ATP’s does one NADH make normally?

3 ATP

How many ATP’s does one FADH2 make normally?

2 ATP

Why does FADH2 only create 2 ATP?

it comes into the series of reactions later in the chain, hence less ATP is created

How much net ATP does anaerobic glycolysis produce?

2

How much net ATP does aerobic glycolysis produce with MAT transport?

2 + 6 = 8 total

How much net ATP does aerobic glycolysis produce with GPT transport?

2 + 4 = 6 total

Major function of oxygen

to create energy within the cells because, without it, there is minimal energy produced