University:
Glendale Community College
Course:
BIO160 | Introduction to Human Anatomy and Physiology
Academic year:

2022
Views:

45

Pages:

7
Author:

Jayla Conner

Section 8.2: Gluconeogenesis §Gluconeogenesis - formation of new glucose from precursors in the liver §Precursor molecules - lactate, pyruvate, a-keto acids §Gluconeogenesis Reactions §Reverse of glycolysis §Except three irreversible reactions §Hexokinase, PFK-1, Puyruvate kinase §Stimulated by high concentrations – lactate, glycerol, amino acids Section 8.2: Gluconeogenesis Figure 8.11 Carbohydrate Metabolism: Gluconeogenesis and Glycolysis Section 8.2: Gluconeogenesis Figure 8.11 Carbohydrate Metabolism: Gluconeogenesis and Glycolysis Section 8.2: Gluconeogenesis Figure 8.12 Cori Cycle Gluconeogenesis Substrates 1. Lactate—released by skeletal muscle from the Cori cycle § Transported to liver lactate, converted to pyruvate by lactate dehydrogenase, then to glucose 2. Glycerol—a product of fat metabolism § Transported to liver in blood, converted to G-3-P by glycerol kinase Section 8.2: Gluconeogenesis Figure 8.13 The Glucose Alanine Cycle §Glucose Alanine Cycle §3. Alanine—generated from pyruvate in exercising muscle §Alanine transaminase converts to pyruvate then glucose in the liver Section 8.2: Gluconeogenesis Gluconeogenesis Regulation § Stimulated - high lactate, glycerol, amino acid conc §Allosteric modulators: §pyruvate carboxylase §pyruvate carboxykinase + Figure 8.14 Allosteric Regulation of Glycolysis and Gluconeogenesis Activator (+); inhibitor (-) Section 8.2: Gluconeogenesis Gluconeogenesis Regulation §Allosteric modulators: §glucose-6-phosphatase §fructose-1,6-bisphosphatase §Hormonal regulation §Alter concentrations of allosteric effectors & key enzymes Figure 8.14 Allosteric Regulation of Glycolysis and Gluconeogenesis Activator (+); inhibitor (-)