Ch 37 Nutrient Use/Storage

Absorptive state

after a meal, when food is in gut and nutrients absorbed

• nutrients used for energy or stored

• occurs in small intestine

postabsorptive state

stomach and small intestine are empty and metabolism run on stored nutrients

• stored nutrients are released and used

2 ways blood glucose concentration increases

• glycogenolysis - breaking down glycogen into glucose

• gluconeogensis - making new glucose from non carbohydrate sources (glycerol)

insulin

releases and stimulates cells to take up glucose when blood glucose rises

• insulin transports - increases glucose transporters (GLUTs)

• lowers concentration of glucose in blood to maintain range

absorptive state, glucose increase

insulin lowers concentration of glucose in the blood to maintain normal range

postabsorptive state, glucose decreases

insulin secretion stops, pancreas release glucagon

• glucagon promotes glycogenolysis & gluconeogenesis                 = glucose ↑