DD. Digestive System Anatomy and Physiology and Metabolism

a HAPS objectives
-hormonal & neural regulation of metabolism
-energy balance, metabolic rate, & thermoregulation

QCP does not model each part of the digestive system.  But it models the overall digestion, absorption and assimilation of  food;
& the regulation of metabolism, including some hormones' actions, the effects of alterations in caloric intake, & body temperature regulation.  We begin by following the processing of a normal meal, using a revision of instructions supplied with QCP, and then repeating the experiment after making Mr. Norm diabetic.

Start QCP, add all items under VIEW.  Record 12.00 values in the table below. 
Find meal masses > GI tract (yellow tube), plasma values > red blood cells logo > chemistry!,
insulin & glucagon > hormones  = green/red fit; & nutrient utilizations under metabolism (flame),
& get yellow liver values. 
Then go to daily planner (clock) control & SWITCH ON > Mr. Norm now gets 3 meals a day. 
Breakfast is at 7 am, so advance to that time to record fasting values,
and then advance in 10 minute intervals, completing a column at each time. 
Restart & reset daily planner to ON.  Select the pancreas (feather), beta cells (insulin). 
Set synthesis basic rate & secretion basic fraction to 0. 
Collect data during another breakfast, & then GO for 1 dy, wk & month.

                                      NORMAL                                             DIABETIC                            CHRONIC
Time                              12.00  7am  7.10  7.20  7.30  8.00  9.00  7.10  7.20  7.30  8.00  9.00      1dy  1wk  1m
Carb mass GI lumen________________________________________________________________
Fat mass, GI lumen ________________________________________________________________
Protein mass GI lumen ______________________________________________________________
Plasma [glucose] __________________________________________________________________
Plasma [fatty acids] ________________________________________________________________
Plasma [triglycerides] ______________________________________________________________
Plasma [ketoacids] _____________________________________________________________
Plasma [insulin] ____________________________________________________________
Plasma [glucagon] ________________________________________________________________
Tissue glucose use _______________________________________________________________
Tissue FFA use _______________________________________________________________
Fat Triglyceride uptake  _______________________________________________________________
Liver glycogen mass _______________________________________________________________
 
Work with one row at a time, decide if the normal response to a meal looks ok, then look for differences in the diabetic,
and explain them.

Starvation

An initially well fed human can survive on water only for about ........ days? 
During starvation homeostasis is maintained as well as is possible by living off oneself. 
Most carbohydrate reserves are used up first, then stored fat, then protein. The last is not a reserve but tissue like muscle. 
An untreated insulin dependent diabetic has some similarities to a starving person why?

..............................................................................................................................................
Starving people usually suffer from edema, they are even skinnier than they look. 
The edema results from a fall in plasma proteins, as there are insufficient amino acids for plasma protein manufacture.
With less plasma colloid osmotic pressure, water seeps out of capillaries into tissues.

We test starvation on Mr. Norm by putting the three basic nutrients to 0 (fork).  Monitor the following:
Will blood pressure be maintained? ..............................................................................
Cardiac output?........................................................................................... .
Nitrogen excretion (yellow test tube)?...........................................................................................
Metabolic acidosis may result why (red test tube)?..................................................................................... ...
Will metabolic rate rise or fall (flame)?.............................................................................. .. ......
Plasma protein (red test tube)?................................................................................................... ..
Blood volume (H2O)?................................................................................................. ...........
Body weight (main chart)? .................................................................................................. ............

Take data each week and run for 60 days.  Where Mr. Norm disagrees with your predictions what do you think is the reason?
Is there edema at 60D?  How is Mr. Norm feeling at the end?  Is this what you expected?

#44. Cold Exposure, revision
Heat Stress, Cold Exposure and Heat Stroke can all be tested on Mr. Norm

How does QCP handle a January day in Indiana?  His day begins warm, but it gets colder, as a lot of Arctic air is coming in. QCP is lightly clothed, so this will be stressful.  Every six hours or so drop the ambient temperature by about 10 dergrees F

Follow body temperature, metabolic rate, skin blood flow, evidence of shivering (muscle blood flow)? and sympathetic nerve activity, any hormones?

Define each variable in your own words, and then explain the cause and/or value to QCP of each variable change with falling ambient temperature. What is the body control system that is making these Variable changes?

Where in the body is this control system's integrating center?

How does the body decide that it must make the changes?

How are the changes made? (trace the pathway(s) from the control center to the effector(s)).

Describe the redistribution of blood flow to the different body regions (see circulation logo).

Find a parameter to change (not ambient temperature or sympathetic nerve activity) to help Mr. Norm to handle the cold, and show that it works.

How realistic do you think this model is in his response to exposure to cold?