ALTERNATE PATHWAYS, CONTROL OF CELLULAR RESPIRATION AND BMR

1. ALTERNATE PATHWAYS, CONTROL OF CELLULAR RESPIRATION AND BMR

2. Alternate Pathways • What are the other fuel sources that can be used in Cellular Metabolism?

3. Fats Carbohydrates Proteins Amino acids Fatty acids Glucose Glycerol Glycolysis Glucose Glyceraldehyde-3- P NH3 Pyruvate Acetyl CoA Citric acid cycle OXPHOS

4. Glycerol can be converted to G3P

5. Beta Oxidation Do not memorize this series of steps. Simply understand that fatty acids get turned into Acetyl-CoA to be used in the Krebs Cycle in a series of steps call Beta Oxidation. Triglycerides are an important fuel source because they yield more than twice as much energy for the same mass as carbohydrates or  proteins.

6. Protein Catabolism • Proteins are digested into individual amino acids • Amino groups are removed in a process call deamination producing ammonia (NH3) a toxin. • Other reactions convert the remaining portion of the amino acid into various components of glycolysis or the Krebs cycle. • The point of entry depends on the identity of the Amino Acid • E.g. leucine  acetyl CoA, alaninepyruvate, and proline  alpha ketoglutarate.

7. PFK - an important allosteric enzyme

8. Basal Metabolic Rate • The BMR accounts for 60 – 70% of the energy a human body uses in a day. • BMR is measured in units of kilojoules per square metre of body surface (BSA) per hour (kJ/m2/h) • BMR = energy used in a day (kJ) ÷ BSA (m2) ÷ time (h) • A nomogram is a graphical method that can be used to determine the value of an unknown quantity when the values of other quantities that it is mathematically related to are know. This method can be used to find the BSA.

9. Nomogram for BSA