Question

Assignment: Topic: This week we covered the details of Cellular Respiration. Your assignment this week is in two parts. Using Excel (or some other Table creating program) create a table that describes the four sub-steps of cellular respiration. Insert the table into a Word document and provide a discussion of how each sub part contributes to overall process of cellular respiration. Assignment Expectations: . Minimum of 1000-1250 words, not including the title or References pages (typed, 12 point font, double spaced). • Required Table must be included in the essay. • The Table must contain these headings: Sub-step reactants, Sub-step products, ATP contribution by sub-step, Cellular location of sub-step. • Support your content with at least (3) citations. Make sure to reference the citations using APA writing style for the presentation

Answer 1

Cellular respiration involves biological oxidation of organic molecules and results in the release of energy in the form of ATP. Four sub-steps of cellular respiration includes Glycolysis, Link reaction, Krebs cycle and Electron transport system (ETS).

Sub-stages	Reactants	Products	ATP contribution	Location
Glycolysis	Glucose(1 molecule)	Pyruvic acid (2 molecules)	Net gain of 2 ATP molecules via substrate level phosphorylation.	Cytoplasm of cells
Link reaction (pyruvic acid to acetyl-CoA)	Pyruvic acid(2 molecule)	Acetyl-CoA(2 molecules)	No direct ATP is formed	Mitochondrial matrix
Krebs cycle	Acetyl-CoA+oxaloacetic acid(OAA)	Different intermediate carboxylic acid compounds like succinic acid, malic acid,etc.	2 ATP formed via substrate level phosphorylation	Mitochondrial matrix
Electron transport system (ETS)	NADH+H+, FADH 2	metabolic water along with ATP via oxidative phosphorylation	Total of 34 ATP formed (6 ATP from glycolysis, 6 ATP from link reaction and 22 ATP from Krebs cycle)	Inner mitochondrial membrane.

So, a total of (2+2+34)=38 ATP is formed in the entire process.

In glycolysis, glucose is broken down to pyruvic acid in absence of oxygen; there is a net gain of 2 ATP in this process and 2 molecules of NADH+H+ formed undergoes ETS to yeild 6 ATP. The pyruvic acid in presence of oxygen is converted to acetyl-CoA via link reaction yeilding 2 NADH+H+ molecules. The acetyl-CoA condenses with oxaloacetic acid to give different intermediate compounds and give 6 NADH2, 2 FADH2 and 2 direct ATP which in ETS yeild 34 ATP. The main purpose of this is to generate ATP from the breakdown of organic molecules via oxidation for the purpose of its utilisation in human body.