Metabolic Nutrition Study Guide

NTFS 4536 Metabolic Nutrition
Study Guide for Exam 3

Chapter 7: Integration & Regulation of Metabolism: Fed versus Fasted State

1. What can be used to make fat?

 Carbs can be converted to fat, however lipogenesis from glucose is less effective o Weight gain from CHO thought to be caused by sparing lipolysis rather than direct CHO lipogenesis o PDH Complex main link of glucose metabolism to FA synthesis (pyruvate  acetyl CoA)
 Most AAs can serve as precursors for fat synthesis

2. What can Acetyl CoA be used for?

 Acetyl CoA must be used for energy, lipgenesis, cholesterogenesis, or ketogenesis o Not Glucogenic

3. What do amino acids and fatty acids produce during gluconeogenesis?

 Amino acids and fatty acids are oxidized to generate NADH & ATP needed for gluconeogenesis (b/c when liver is producing glucose, it cannot synthesize lipids and proteins at the same time)

4. What is produced during hepatic lipogenesis?

 Glucose must be used to produce NADPH and ATP necessary for the conversion of acetyl CoA to fatty acids

5. What are the two intermediates that the TCA cycle provides that cross-link CHO, proteins, and lipids?

 Oxaloacetate (OAA) and a-ketoglutarate

6. What is the purpose of citrate?

 Citrate moves from mitochondria to cytoplasm, where it is broken down to OAA and acetyl CoA (initiator of FA synthesis)

7. What is the purpose of malate?

 Malate may provide a portion of the NADPH required for reductive stages of FA synthesis

8. Know what is happening to the body/organs during a fed state. What pathways are being used? What hormones are secreted? What products are being produced? What enzymes are involved in covalent modification?

 Fed state lasts 3 hours after a meal
 RBC & Central Nervous System o RBC have no mitochondria and can only burn glucose anaerobically (glycolysis & gluconeogenesis) and CNS has no metabolic mechanism to convert energy stores
 Glucose available