1. Homeostasis of Plasma Glucose Concentration
Normal physiological range: mg/dl
Set point?
Plasma glucose concentration = glucose entering the plasma – glucose leaving the plasma
What are the mechanisms that regulate plasma glucose concentration?
What are the components of the negative feedback loop:
Glucose receptors?
Afferent pathway?
Integrator?
Efferent pathway(s)?
Effector organ(s)?
Phases: *absorptive, *post-absorptive, and fasting

3. Fig
Absorptive Phase
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4. Fig
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Post-absorptive phase

5. Major Points Absorptive phase lasts ~ ___ hours
During absorptive phase, energy needs provided by recently digested food
During absorptive phase, excess is converted to stored fuel
During post-absorptive phase, energy need met by release of stored fuels
Fasting defined as greater than __ hours after previous meal (some say __ hrs)
Fasting for several days has ____effect on plasma glucose levels

6. The Issues How do cells “know” which fuel to “burn?”
How do cells “know” when to synthesize glycogen or lipids and when to break down glycogen or lipid?
What is responsible for the transitions from the absorptive and post-absorptive states?

7. Islets of Langerhans

8. Activates some enzymes, inactivates others

9. Fig
Absorptive Phase
16.01.jpg

11. Fig
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12. Fig
Id sensors, afferent pathway, integrator, efferent pathway, effectors
16.07.jpg