Homeostasis Flashcards
(69 cards)
1
Q
what percentage of our body is water
A
60%
2
Q
ICF is what percent of total body water
A
2/3
3
Q
ECF is what percent of total body water
A
1/3
4
Q
what is ICF
A
anything inside cell
5
Q
what is ECF
A
anything outside cell
6
Q
what two compartments are in ECF?
A
plasma, interstitial fluid
7
Q
plasma
A
blood cells, plasma proteins
8
Q
interstitial fluid is what
A
ultrafiltrate of plasma
9
Q
difference b/w females and males in total body water
A
60% for males
55% females
10
Q
what percentage is interstitial fluid and plasma
A
80% interstital fluid
20% plasma
11
Q
4 important constitutents of ECF
A
Na+
K+
Ca++
Cl-
12
Q
Na+ in ECF amount
A
142 mEq/L
13
Q
K+ ECF
A
4 mEq/L
14
Q
Ca++ ECF
A
2.4 mEq/L
15
Q
Cl- ECF
A
103 mEq/L
16
Q
Na+ ICF
A
10 mEq/L
17
Q
K+ ICF
A
140 mEq/L
18
Q
Ca++ ICF
A
.0001 mEq/L
19
Q
Cl- ICF
A
4 mEq/L
20
Q
phosphates ICF
A
75 mEq/L
21
Q
sodium potasium ATPase does what
A
3 sodiums out for every two potassiums in
22
Q
if sodium is 142 on inside of cell
A
you will die
23
Q
as many potassium ions go out (postiive charge goes out) what happens to keep homeostasis
A
as many leave, that many go back in cell
24
Q
what is the unit to describve ion quantitites
A
miliequivalent per liter
25
what is a concentration gradient
different concentrations for sodium to go into cell
26
when an ion is going to move, how does it move
toward the lower concentration gradient
27
if only concentration gradient is there, where will ion go
"downhill" so Na+ would go from 142 to 10, so it would go inside cell
28
the bigger the concentration gradient
the faster the ion will move
29
what is major anion and cation inside cell
cation: potassium
anion: phosphates
30
what is major anion and cation outside cell
cation: sodium
anion: chlorine
31
Draw graph of major anions and cations inside extracellular and intracelluar
slide 6 homeostasis
32
osmolality is:
whatever is in the compartment, like beaker of water. add sodium chloride. add 142 mE/L ,all the solutes impart osmotic pressure and would impart it on a cell if the cell goes inside beaker, they would put pressure on cell membrane. it is the number of solute molecules at concentration x number of solute molecules that can be disassociated
33
osmolality vs osmolarity
osmolarity is expressed as mOsm/L
osmolality is mOsm/kg
osmolarity is volume, osmolality is weighing it. they are very similar to each other
34
what is ECF and ICF osmolality
290 mOsm/kg
35
osmotic pressure
difference in solute concentration
36
osmotic pressure does what to water
causes it move if there is osmotic gradient
37
what is normal osmolarity
285 mOsM
38
what is the osmolarity in ECF and ICF
285 mOsM for both
39
what are the five components of homeostatic control system
1. stimulus
2. change detected by receptor
3. input
4. output
5. response
40
variable example for homeostatic control
blood pressure
41
as soon as variable deviates enough from set point what happens
sensor notices and sends information to control sensor
42
describe negative feedback control system
some variable is off balance, like it being 80 degrees in apartment, it brings it back down to normal range, like air condition turning on and cooling off apartment to 75
43
a person eats, causes raise in blood glucose level, this does what to sensors
stimulates
44
what cells are stimulated as results of increased blood glucose lvels
beta cells of pancreas - they release insulin into blood
45
what is the result of negative feedback mechanism after eating
blood glucose levels go back down
46
if diabetic person is not eating, person is drinking too much, hepatitis or kideny disorders, they would all result in
lowered blood glucose levels
47
deviation from normal blood glucose - lower blood glucose, stimulates what sensors
alpha cells in pancreas
48
alpha cells in pancreas release what
glucagon
49
what is restult of negative feedback of low blood glucose
blood levels go back to normal
50
if blood pressure is increased, ex: 140/90, it stimluates what sensors
baroreceptors in carotid sinuses and aortic arch
51
what do baroreceptors respond to
stretch due to increase bp
52
how does brain interrpret barorecptors
electircal activity - increase firing rate of AP going to brain
53
centers in brain integrate info in brain, and do what in responde to high BP
decrease sympathetic impulses to heart → decrease HR
Decrease contractility and decrease CO (cardiac output)
increase parasympathetic
54
acetylcholine binds to receptors in heart and does what
decreases heart rate
55
when norepinephrine is realeased from sympathetic nervous system it goes to what receptors
alpha *echo*
56
list steps of negative feedback to decrease BP
pg 14
57
decrease in BP, acts on baroreceptors and electrical activity does what
decrease impulse/frequency to brain
58
if low BP, what happens to baroreceptors
less stretch/pressure
59
list steps for negative feedback of low BP
pg 15
60
go through thermoregulation - increase in temp. negative feedback steps
pg 17
61
go through thermoregulation - decrease in body temp. negative feedback steps
pg 18
62
negative feedback purpose:
stabilize system
63
positive feedback purpose:
destabilize system
64
what happens in positive feedback
initial deviation, initial parameter (ex: increase) is amplified, and is continued to be amplified. for positive feedback you want to reach a certain endpoint
65
Ex: of positive feedback
giving birth
66
go through steps of positive feedback of childbirth
pg 20
67
voltage-gated sodium current is an example of what feedback
positive
68
go through positive feedback of voltage-gated sodium channels
pg 21
69
ECF osmolality is roughly
300 mOsm/kg H2O
