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