BIOL 1412 Study Guide - Winter 2018, Comprehensive Midterm Notes - Ficus, Stim, Neuron
12 Oct 2018
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BIOL 1412
MIDTERM EXAM
STUDY GUIDE
Fall 2018
1
TOPIC I: INTRODUCTION TO PHYSIOLOGY:
A) What is physiology?
- study of how the body functions
- hat does this syste do ad ho does it do that? fig. 1.02
- the cell is relieving their waste in the ECF and also feeds from it; look at drawing.
- anatomy is was the body is and physiology is what the body does.
B) Homeostasis all that you are trying to do is trying to maintain homeostasis!
- the ability to maintain relatively stable conditions in the internal environment (despite
changes in the external environment)
there are different ways to maintain it; it doesn't necessarily mean only with physiology but
also behavior (dress more or dress less)
- cells can only survive within a narrow range of conditions
- ∴ body conditions must be maintained within physiological limits if you dot
your cells can start to die)
- conditions controlled include:
1) pH (need to keep this and temp. regulated because it stops your
protein from changing shapes)
2) temperature
3) blood gases (CO2, O2)
4) blood pressure (b.p.)
5) intracellular + extracellular (ICF + ECF) fluid volumes (too much fluid =
too dilute, too little fluid = too concentrated)
6) etc.
- organ systems function together to maintain homeostasis
- if you do not maintain homeostasis you will develop diseases and die
- disease = failure to maintain homeostasis
- nervous and/or endocrine system(s) control all other systems (control centers)
- act to: (edocrie syste = iteral orgas that ill start up the N“
1) maintain homeostasis (by monitoring it)
2) permit departures from homeostasis in a controlled manner e.g. pregnancy
(your body is changing to suit the baby for 9mnths), growth, sudden fright
C) Homeostasis Regulation:
- Change in internal environment must be detected or anticipated
- then NS and/or endocrine system responds, altering system(s) responsible
for that condition
- Types of NS/Endocrine responses: fig. 13.16
1) Anticipatory Responses (know that something that you know is going to
change so you act before it does)
- e.g. the person who was afraid of spiders began to feel fear prior to the spider being seen.
Basically everything
that you do will change
your homeo. Like laying
down or eating.
find more resources at oneclass.com
find more resources at oneclass.com
2
e.g. ↑ respiratory rate at start of exercise → proprioceptors (receptors in
the joints and muscles that indicate body movement) (NS sensory
receptors) signal movement before a change in internal
conditions occur (gases in blood)
- may also be learned or behavioral
e.g. in wpg you know that in the winter it gets really cold, you
don't need to go on the radio or news to know that is will feel cold so you put on coat
2) Feedback Mechanisms (you have to have a change occur to have a response)
- mechanisms that respond to a change in the system
- consist of set points, receptors, control areas and effectors
- Set point = range of values of variable (e.g. body temperature) that does
not bring about a response i.e. oral range
- he youre i that set poit rage you are i hoeo.
- Variable is monitored by receptors → info (input) fed back to control
area (NS, endocrine gland) → output to effector → response
iput output
‘eceptors ‘ → cetral cotrol → Effectors (E)
(stimuli) (nervous or endocrine) (muscle/glands)
- stimulus detected receptors detect a change receptors sends info (input) to Control
Center CC sends signals to activate Effector response by Effector counters the
imbalance to return the variable back to homeo.
- Types:
a) Negative Feedback
b) Positive Feedback
a) Negative Feedback
- brings the body back to its set point!
- most common homeostatic control mechanism
- result of output - variable moves back toward the set
point i.e. in opposite (negative) direction to the
change that triggered the response iput
- if it goes it the feedback will go down, and if it doe down
it will go up
- e.g. 1: body temp. (= variable): set point = 36 - 37.8⁰C. If
↑ temp. (e.g. 40⁰C):
- Hypothalamus thermostat cells (R) detect high
temp. (stimulus)
↓ iput
Brain (NS) (central area)
find more resources at oneclass.com
find more resources at oneclass.com
