Consider a glucose molecule that was taken up by aerobic eukaryote, anaerobic prokaryote and facultative anaerobe prokaryote cell- what will be the fate of this molecule? How will each of these cells metabolize it and how much energy will each get? Emphasize on what are the most important charcteristics of glycolysis, Kreb's cycle and ETC- what is starting substrate, what is product and where does it take place.

There can be 3 fates of glucose molecule based on different types of organisms.

1.

For aerobic organisms glucose undergoes three different pathways;

Glycolysis

Kreb cycle

Electron transport chain

In glycolysis the end product is 2* (pyruvic acid) and 2*NADH and 2* ATP. Starts from 1 molecule of Glucose. Occurs without oxygen.

In TCA cycle ,end product is 2 ATP , 6 NADH and 2 FADH2. Starting material is Acetyl CoA.

In electron transport system, the end product is net of 32 ATPs. Comprise of 5 Complexes of enzymes which convert high energy substrate to ATPs.

2.

For facultative anaerobes they have slightly different pathways which ultimately leads to 2*(Lactate) and 2 ATP from 1 glucose molecule. The end product of glycolysis, pyruvic acid is converted to lactic acid

3.

For anarobes prokaryote they form ethanol and Carbon dioxide from the pyruvate.

The end product of glycolysis (pyruvate) is used to synthesize ethanol and CO2.The process occurs in the cytosol and is referred to as fermentation