Physiology Flashcards

1
Q

What is feedforward?

A

a change made in anticipation of a change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is feedback?

A

a change after a change has been made

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the three functions of the lipid bilayer?

A

structure
hydrophobic interior is a barrier
fluidity of the membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the two types of proteins in the lipid bilayer?

A

peripheral aren’t embedded

integral either span, half span or are lined to an embedded protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the functions of integral proteins?

A
ligand-binding receptors 
adhesion molecules
pores or channels
carriers
pumps
enzymes
intracellular signalling
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What do docking-markers do?

A

on inner membrane surface and interact with secretory vesicles leading to exocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the glycocalyx?

A

sugar coating of glycoproteins and glycolipids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the roles of carbohydrates in cell membranes?

A

different markers for embryonic development

tissue growth so tissues don’t overgrow territory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is pulse pressure?

A

difference between systolic and diastolic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How is MAP calculated?

A

((2xdiastolic) + systolic)/3)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the minimum MAP needed and why is it needed?

A

60mmHg and must be high enough to perfuse brain, heart and kidneys but not too high that vessels burst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where are the baroreceptors?

A

aortic arch and in the carotid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What happens to the firing rate of the baroreceptors when MAP increases?

A

increased rate of firing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What happens to the firing rate of the baroreceptors when MAP decreases?

A

decreased rate of firing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What happens to CNS afferent impulses that reach the cardiovascular control centre?

A

info sent to brain areas
generates vagal outflow to the heart
regulates spinal sympathetic neurones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does MAP equal and what does CO equal?

A

MAP=COxSVR

CO=SVxHR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does noradrenaline act on to change HR and what does it cause?

A

beta 1 receptors to cause tachycardia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does acetylcholine act on to change HR and what does it cause?

A

muscarinic receptors to cause bradycardia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Does parasympathetic or sympathetic affect ventricular contraction?

A

only sympathetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What does vasoconstriction do?

A

increases SVR and MAP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does vasodilation do?

A

decreases SVR and MAP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What does noradrenaline act on to change vasoconstriction/vasodilation?

A

alpha receptors to produce parasympathetic vasomotor tone at rest

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Which one does not innervate the arterial smooth muscle- sympathetic or parasympathetic?

A

parasympathetic does not innervate the arterial smooth muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What does increased sympathetic discharge do to SVR?

A

increases it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What does decreased sympathetic discharge do to SVR?
decreases it
26
What is the process of events after there is a decreased ABP?
decreased baroreceptor discharge CV centre in medulla causes - decreased vagal so increased HR so increased CO so increased ABP - increase sympathetic so increased SV and HR so increased CO so increased ABP - increased sympathetic constrictor tone so increased venoconstriction (increased SV) and increased vasoconstriction (increased SVR)
27
What is the process of events after there is a increased ABP?
increased baroreceptor discharge CV centre in medulla causes - increased vagal so decreased HR so decreased CO so decreased ABP - decrease sympathetic so decreased SV and HR so decreased CO so decreased ABP - decreased sympathetic constrictor tone so decreased venoconstriction (decreased SV) and decreased vasoconstriction (decreased SVR)
28
Why do baroreceptors only provide short-term control of ABP?
they re-set at a higher steady state
29
What is normal body temperature?
37.8
30
What is normothermia?
the optimum temperature for cellular metabolism and function
31
What is normal tympanic temperature?
(ear drum) | 35.5-37.5
32
What does the body gain heat from?
metabolism radiation convection conduction
33
What does the body lose heat from?
conduction, convection, radiation and evaporation
34
What is basal metabolic rate?
minimum amount of energy required to sustain the body
35
What is the basal metabolic rate increased by?
hormones (adrenaline, noradrenaline and thyroxine)
36
What does conduction depend on?
temperature gradient and thermal conductivity
37
Where are the central thermoreceptors?
hypothalamus and abdominal organs
38
Where are the peripheral thermoreceptors?
skin
39
What are the temperature effectors?
skeletal muscles skin arterioles sweat glands
40
What is the posterior hypothalamic centre activated by?
cold
41
What is the anterior hypothalamic centre activated by?
hot/warmth
42
What happens in the cold response?
vasoconstriction increased muscle tone shivering increased voluntary muscle movement
43
What happens in the hot response?
vasodilation sweating decreased muscle tone decrease voluntary movement
44
How is the temperature reset in fever?
chemicals from macrophages act as endogenous pyrogens stimulate the release of prostaglandins in hypothalamus reset thermostat to higher temperature initiate cold response to heat body to new set point fever
45
What stops fever?
stopping pyrogen release
46
What temperature is fever?
38-40 degrees
47
What temperature is hyperthermia?
above 40 degrees
48
What temperature is hypothermia?
below 35 degrees
49
What are the factors affecting Fick's law of diffusion?
``` concentration gradient magnitude of surface area lipid solubility molecular weight of substance diffusion distance ```
50
What is electrochemical gradient?
net effect of simultaneous electrical and concentration gradients on the ion
51
What is osmolarity?
the concentration of osmotically active particles in a solution
52
What is tonicity?
the effect a solution has on cell volume (iso-hypo-hypertonic)
53
What are the types of selective transport?
carrier-mediated | vesicular
54
What is carrier-mediated transport determined by?
specificity saturation competition
55
What is Tm?
the levelling off when all carriers are full
56
What are the types of carrier-mediated transport?
facilitated diffusion | active transport
57
What is primary active transport?
energy required directly to move substances against their concentration gradient
58
What is secondary active transport?
energy require but not used directly, carrier moves molecule uphill by secondhand energy store in the form of an ion concentration gradient
59
What are the roles of the sodium-potassium pump?
established these ions' gradients regulates cell volume energy driving the pump serves as energy source for secondary active transport
60
What are the types of secondary active transport?
symport (same direction) | antiport (opposite directions)
61
How is Em created?
differences in concentration and permeability of key ions
62
What are the permeabilities of K+ and Na+ across the membrane?
the membrane is much more permeable to K+ than Na+ (100x)
63
What ions can't move across the membrane?
large negatively charged anions
64
What are the two forces moving K+ ions?
concentration gradient which moves them out | electrical gradient which moves them in
65
What is the normal membrane potential of Ek?
-90mV
66
What is the Nernst equation used to calculate?
the equilibrium potential for any ion
67
What are the forces acting on Na+?
concentration gradient moves them in | electrical gradient moves them out
68
What is normal Ena?
+61mV
69
What is resting potential for a cell and why?
-70Mv as K+ permeability is higher so the membrane favours the equilibrium of K+ over that of Na+
70
What does the Na+/K+ pump do?
maintains the K+ and Na+ gradient and has a slight hyper polarising current
71
What is the most important factor in setting the Em?
K+ gradient