Question

Chemoorganotrophic heterotrophs oxidize carbohydrates as their primary source of energy. Glucose is the most common energy source for such organisms and energy may be extracted from glucose via respiration or fermentation.

a.   Explain the difference between aerobic respiration, anaerobic respiration, and fermentation.

b.   Identify and briefly define the metabolic pathways involved in aerobic respiration. For each metabolic pathway your response should address the forms of carbon that enter and exit, the amount of ATP produced, and the number and types of electron carriers generated.

c.   Briefly describe the process of anaerobic respiration and indicate how much ATP is produced. (HINT: a good approach would be to compare and contrast anaerobic respiration with aerobic respiration.)

d.   Briefly describe fermentation and compare and contrast it with aerobic respiration and anaerobic respiration. Also, explain why fermentation reactions are useful to so many microbes and why microbes use fermentation rather than, or in addition to, respiration.

                                                            

Answer 1

a.

Aerobic respiration	Anaerobic respiration	Fermentation
Needs oxygen for the conversion of energy into ATP.	Conversion without oxygen	without oxygen
Final product is CO2 and water	lactic acid	final product is lactic acid
newer process	older	older
Location is cytoplasm and mitochondria	in cytoplasm	occurs in cytoplasm
complete oxidation		incomplete oxidation
38 ATP produced	2 ATP	2 ATP

b.Aerobic respiration is the production of cellular energy with help of oxygen.The steps involves

• Glycolysis-Here glucose is the first product and end product is pyruvic acid.Here 2 ATP and 2 NADH molecules are produced
• citric acid cycle-Here the Process starting with oxidation of acetyl coA and finally into adenosine triphosphate and CO2.Here 2 ATP ,10 NADH,2 FADH2 are formed
• electron transport chain-Here protons from NADH and FADH2 to molecular oxygen formed.Here 34 ATP formed

c.In anaerobic respiration and glycolysis takes place,the product pyruvic acid in absence of oxygen converted to lactic acid in animals and ethanol in yeast.here .It makes a total of 2 ATP.It is less effective compared to aerobic respiration

.

Aerobic Respiaution. [ՆՆ ԱՆ»)՝ -6 17 Gluose ADP -2A1P Glucose 6-Po4 CATP Election tounspust Cheun & Fructose 6-04 Glyceraldehyde 3-Pch , 7 2 NADA! ZNADH 1.3. diphosphoqly clock NADH ATP 13 Phosphoglycerate 7202 LAD / Ketiglitati napt NADH citoute Krebs Sulchyteco Net Cycle FAD CFADH₂ Fumarah pl. 2 phosphoend pyourate 2A (2ADb & CRAIP youvate] COA NADT oxaloacetate NADH

d.Fermentation converts a sugar into alcohol. It takes place in the absence of Oxygen.Here the reduced NADH produced converted back to NAD+..Net energy is 2 ATP,no net NADH production.In the case of microbes fermentation is a primary method for producing ATP by the degradation of organic nutrients in tha absence of oxygen