MODULE 1

Question 1

Physiology

Answer 1

the study of the normal functioning of a living organism and its component parts, including all its chemical and physical processes

Question 2

physiology is an integrative science
Emergent Properties:

Answer 2

properties of a complex system that cannot be explained by a knowledge of a systems individual components
-result from a complex, nonlinear interactions of the systems different components

Question 3

physiology is an integrative science
closely tied to anatomy:

Answer 3

the structure of a cell, tissue or organ must provide a physical base for its function

Question 4

Levels of organization
Smallest to largest

Answer 4

atoms - molecules - cells - tissues -organs - organ systems - organism - populations of species - ecosystem of different species - biosphere

Question 5

cells

Answer 5

smallest unit of structure capable of carrying out life process

Question 6

4 types of major cells

Answer 6

epithelial, connective, neuron and muscle

Question 7

tissue

Answer 7

collection of cells carrying out related functions

Question 8

organ

Answer 8

formation of tissues into a structural and functional unit

Question 9

organ system

Answer 9

integrated groups of organs

Question 10

physiologists often focus on a __________ approach

Answer 10

mechanistic

Question 11

homeostasis

Answer 11

The ability to maintain a relatively stable internal environment in spite of exposure to external variability
Homeostasis and regulation of internal environment are key principles in physiology
ex. blood pressure body temp, ion/molecuel concentration, gas partial pressures ect.

Question 12

Homeostasis and Disease

Answer 12

If for some reason you cannot maintain homeostasis you will likely be in a disease state

Question 13

Homeostasis and Disease
external changes:

Answer 13

toxic chemicals
physical trauma
forge in invaders (bacteria or viruses)

Question 14

Homeostasis and Disease
Internal changes:

Answer 14

normal cell growth
autoimmune disorders
genetic disorders

Question 15

Homeostasis and Disease
what happens with internal and external change

Answer 15

organisms attempt to compensate
if compensation fails = illness or disease
if compensation succeeds = wellness

Question 16

internal environment of the body

Answer 16

extra cellular fluid: surrounding cells is a buffer between cells and the external environment

Question 17

dynamic steady state

Answer 17

We want to keep extracellular fluid constant, because it affect the intracellular fluid
they are in a dynamic steady state

Question 18

homeostasis depends on mass balance
Law of Mass Balance:

Answer 18

the amount of a substance in the body is to remain constant, any gain must be offset by an equal loss
mass balance = existing body load + intake or metabolic production - excretion or metabolic removal

Question 19

homeostasis does not mean equilibrium

Answer 19

No net movement
The body compartments are in a manic steady state but are not in equilibrium but rather stable disequilibrium
-goal is to maintain the dynamic states of body compartments

Question 20

Control systems and homeostasis
To maintain homeostasis the body monitors certain key functions/variables
Control systems can be ______ or _______

Answer 20

local or reflex

Question 21

all control systems have 3 basic components

Answer 21

1. input signal (change is sensed creating an input signal)
2. integrating centre (takes in the change)
3. output signal (creates an output to return to normal)
   response

Question 22

local control

Answer 22

restricted to tissues or cells involved (smaller area of the body)
ex.
active cells - reduced O2 levels
oxygen levels drop in extracellular tissue
active cells send local signal
O2 levels in tissue restored

Question 23

Reflex control uses long-distance signalling

Answer 23

Changes widespread throughout the body (systemic) use more complex control systems to maintain homeostasis (blood pressure)
Reflex control refers to any long distance pathway that uses the nervous, endocrine system or both

Question 24

Reflex control: broken into two parts

Answer 24

1. Response Loop (nervous and/or endocrine system
2. Feedback loop
   -modulates the response loop
   -feeds back to ultimately influence the input
   stimulus, sensor, input signal, integrating center, output signal, target, response

Question 25

Reflex control can be ______

Answer 25

antagonistic
heater and air conditioner (in the body dual control of heart rate)

Question 26

negative feedback loops

Answer 26

A pathway in which response opposes or removes the signal (stimulus) is known as negative feedback
-stabilizes a system
-homeostatic
-can restore the initial state but cannot prevent the initial disturbance

Question 27

Positive feedback loops

Answer 27

-Are not homeostatic
-reinforce a stimulus to drive the system away from a normal value rather than decreasing or removing it
-requires intervention or event outside the loop to cease the response
no used to maintain homeostasis

Question 28

Feedforward control

Answer 28

Anticipatory reflex
-a few reflex have evolved that allow the body to predict a change is about to occur
ex. salivating when thinking about food, the body has learned this adaptation

Question 29

biological rhythms and changes in set point

Answer 29

variables are regulated within a normal range around a set point but set points vary form person to person or may vary within an individual over time
-can be due to genetics, or constant exposure to a new condition

Question 30

biorhythms

Answer 30

variables that change predicability and create repeating patterns or cycles of changes

Question 31

Example of Biorhytms

Answer 31

circadian rhythm (24hr)
Set point changes throughout the day ex. Temperature - lowest point in the morning 6am rises in the evening
Morning people lowest temp is earlier in the morning temp goes up earlier in the morning
Night people their temp is still dropping