the ability of the body to maintain an internal environment that isoptimal for life
blood pressureblood gases, O2, CO2
blood glucose levels (70-100 mg/dl)osmolarityions-Cl- Ca2+, Na+, K+, body temperature
-homeostasis-integration of the body systems-cell to cell communication-movement of substances and information across cell membranes-compartmentalization-energy flow-mass balance and mass flow
Physiology questions1) How does the body regulate blood glucose levels?
2) After significant blood loss, how does the cardiovascularsystem maintain blood pressure?
3) Why are people with uncontrolled insulin-dependent diabetes mellitus at risk of coma?
4) How does the respiratory system manage to deliver oxygen to the tissues under low oxygen conditions (eg. high
altitudes)?
5) How do the kidneys contribute to the maintenance of normal blood pressure?
Learning physiology
1)terminology
2) local function
3) integration-organismic processes
glucose
pancreas glucose transporter
some of the terminology you need to know to understand glucose regulation
local function-release of hormone
local function-signal transduction
Glucose enters cells via mediated diffusion.
local function-glucose enters cell
Negative feedback
“Normal” conditions
Increase from normal conditions
Increase detected
Changes that reverse the increase
+
-
Negative feedback
“Normal” conditions
Decrease from normal conditions
Decrease detected
Changes that reverse the increase
+
-
Negative feedback
“Normal” conditionsBlood glucose70-110 mg/dl
Increase detectedBeta cells of the
pancreas
Changes that reverse the increase
Release of insulin stimulates cell uptake of glucose—
this reduces the blood concentration
+
-
Increase from normal conditionsEating a meal rich in carbohydrates
Positive feedback
“Normal” conditions
Decrease from normal conditions
Decrease detected
Changes that further decrease theparameter from normal-
-
Negative feedback
“Normal” conditions
Decrease from normal conditionsTHE TEMPERATURE IN THE
ROOM DROPS BY 50 F
Decrease detected
-
What changes take place help maintain body temperature?
Negative feedback
“Normal” conditions
Decrease from normal conditionsTHE TEMPERATURE IN THE
ROOM DROPS BY 50 F
Decrease detected
-
What changes take place help maintain body temperature?
changes that generate or conservebody heat: shiver, curl up, divert blood flow to core, clothing
Positive feedback
“Normal” conditions
Decrease from normal conditionsTHE TEMPERATURE IN THE
ROOM DROPS BY 50 F
Decrease detected
-
What changes take place?
Changes that further decrease theparameter from normal
changes that would further reducebody temperature; divert blood flow to periphery, perspiration
Decrease detected
Negative feedback
“Normal” conditions
Decrease from normal conditions
Changes that reverse the increase
+
-Afferent pathway
Efferent pathway
polar (water)
ionized (sodium chloride=Na+ Cl-)
non-polar (CH3 CH2 CH2 CH3)
hydrophilic=lipophobic
hydrophilic=lipophobic
hydrophobic=lipophilic
“likes dissolve likes”
Units of concentration
1. volumes μl, ml
2. concentration as mass per volume 90 mg/l
3. concentration as molarity (=mole/volume) =
glucose = 5.6 mM
Listed below are the pHs of four different solutions. Which has the highest concentration of free protons?a. pH=7b. pH=8c. pH=4d. pH=1
pH=-[log H+]
=0.0000001 moles H+/liter=0.00000001=0.0001=0.1
=10-7 moles H+/liter= 10-8
=10-4
=10-1