Module 2: Cardiovascular system and blood Flashcards
1
Q
endothelial cells are
A
epithelial cells within the cardiovascular system
2
Q
blood vascular system is
A
a closed supply and drainage system (continuous)
3
Q
lymphatic vascular system is
A
an open entry drainage system (one way)
4
Q
red blood is
A
oxygenated
5
Q
blue blood is
A
deoxygenated
6
Q
purple represents
A
gas exchange
7
Q
green represents
A
lymphatics
8
Q
arteries carry blood
A
away from the heart
9
Q
veins carry blood
A
towards the heart
10
Q
pulmonary circuit involves
A
the heart and lungs
11
Q
systemic circuit involves
A
the body (excluding the lungs) and the heart
12
Q
why are major arteries situated deep (next to bone)
A
as protection to avoid being damaged
13
Q
how many arteries feed important structures
A
2
14
Q
role of capillaries
A
exchange network
15
Q
three types of capillaries
A
continuous, fenestrated, sinusoidal
16
Q
what is the leakiness like in continuous capillaries
A
controlled/ tight
17
Q
what is the leakiness like in fenestrated capillaries
A
leaky
18
Q
what is the leakiness like in fenestrated capillaries
A
very leaky
19
Q
deep veins run antiparallel to what structure
A
arteries
20
Q
superficial veins are
A
large veins as they are low pressure and low velocity so easy to clot
21
Q
the cross sectional area of veins is how much greater than arteries
A
twice
22
Q
veins are ___ pressure, ___ volume structures
A
low; high
23
Q
arteries are ___ pressure ___ volume structures
A
high; low
24
Q
blood in=
A
blood out
25
shape of the heart
blunt, cone-shaped
26
apex of the heart
pointed end, situated on approx 5th rib (midclavical)
27
base of heart
broad end, tilted towards neck
28
the heart is the size of
a closed fist
29
how much of the heart sits to the left
2/3
30
what valve separates the right atrium and right ventricle
tricuspid AV valve
31
what valve separates the left atrium and left ventricle
bicuspid AV valve
32
what valve separates the pulmonary artery and right ventricle
pulmonary semilunar valve
33
what valve separates the aorta and left ventricle
aortic semilunar valve
34
what separates the two ventricles
interventricular septum
35
blood flows from ___ to ___ in the heart
atrium; ventricle
36
function of valves
to prevent backflow of blood from the direction it came from
37
endocardium is
the innermost layer of the heart
38
myocardium is
the middle layer of the heart differing in thickness
39
epicardium is
outer layer of the heart
40
endothelium of the endocardium
squamous
41
endocardium contains
loose irregular fibrous connective tissue, blood vessels and Purkinje (electrical conduction) fibres
42
what side of myocardium is the thickest
right is 3x thicker than due to higher pressure
43
epicardium contains
visceral pericardium, blood vessels, loose irregular adipose
44
pericardium contains three layers outermost to innermost
parietal pericardium, pericardial fluid, visceral pericardium
45
function of AV valve
prevent blood returning to atria during ventricular contraction
46
loading the chambers up with blood is
diastole
47
in diastole the AV valves are ___ and the semilunar valves are ___
open; closed
48
pressure is going up the chamber is
systole
49
in systole the AV valves are ___ and the semilunar valves are___
closed; closed
50
function of semilunar valves
prevent blood returning to ventricles during diastole
51
chordae tendineae
act as parachute chords acting so the valve leaflet doesn't slam shut and flick through to the other side
52
papillary muscle
attach to the chordae tendeae stopping valve slamming
53
position of the right coronary artery
runs the epicardial groove between right atrium and right ventricle, over surface layer of heart wall
54
function of right coronary artery
supplying ventricular wall of right ventricle
55
position of left coronary artery
runs behind pulmonary artery forms a short left coronary artery and then branches to form the anterior interventricular artery.
56
position of interventricular artery
runs over the anterior surface of the heart over the interventricular septum
57
function of left coronary artery/ interventricular artery
supplying left ventricle
58
more muscle on the left side of the heart means the right need a ___ blood supply
lesser
59
great cardiac veins are on what side of the heart
left
60
function of small and great cardiac veins
draining into coronary sinus
61
small cardiac veins are on what side of the heart
right
62
the coronary sinus drains into
the right atrium
63
what type of blood does the right atrium contain
deoxygenated
64
myocardium is another name for
cardiac muscle
65
lots of capillaries around cardiac muscle suggest
it needs a oxygen rich blood supply
66
the myocardium contains
all 3 types of muscle
67
function of myocardium
allows the heart to beat continuously
68
intercalated discs are found in what muscle type
cardiac
69
the presence and position of nuclei in cardiac muscle are
centred and around 1-2 nuclei per cell
70
the sarcomeres in cardiac muscle are
irregular and branched
71
adhesion belts
link actin to actin- vertical
72
desmosomes
link cytokeratin with cytokeratin
73
gap junctions
electrochemical communicator- horizontal
74
function of adhesion belts
propagate contractions between cells keeping them in sync
75
function of desmosomes
keep cells together due to the force of tugging
76
function of gap junctions
help with the synchronisation of contractions
77
function of autonomic nerves
alter the rate of conduction impulse generation
78
function of conduction system of the heart
coordination of heart contractions and of AV valve action
79
SA node
little cluster of cells which generate APs which can be increased by sympathetic nerves or decreased by parasympathetic nerves.
80
SA node is also known as the
rate/ pace maker
81
Internodal pathways
electrical signal passes through these around the chambers when we leave the atrial chambers and get towards the ventricles these unit to a single point
82
AV node
single point where internodal pathways lead this the gate keeper from the atrium to the ventricles
83
Av node goes into
AV bundle
84
AV bundle goes into
right and left bundle branches in the ventricles
85
Purkinje fibres
little branches but these are modified cardiac muscle NOT nervous tissue
86
Ascending means
going up
87
Descending means
going down
88
longest vein in the body is
great saphenous vein
89
three layered wall of blood vessels from outermost to innermost
tunica adventitia (externa), tunica media, tunica (layer) intima
90
3 layers of tunica intima
endothelium, sub-endothelium, internal elastic lamina
91
endothelium of tunica intima
a simple squamous epithelium which lines the lumen of all vessels
92
sub-endothelium is
a sparse pad of loose FCT cushioning the endothelium
93
Internal elastic lamina
a condensed sheet of elastic tissue.
94
which layer of blood vessels is thickest in arteries compared to veins
media
95
which layer of the tunica intima is the thickest in arteries compared to veins
internal elastic lamina
96
tunica media is
smooth muscle
97
the thickness of tunica media is proportional to
both vessel diameter and blood pressure
98
tunica adventitia is
loose FCT with a high content of collagen and variable amount of elastin
99
what is contained within the tunica adventitia in larger vessels
vasa vasorum
100
vasa vasorum is
blood vessels to provide the organ system
101
function of arteriole
the resistance vessels of the circulation determine blood pressure
102
function of capillaries
site of exchange between blood and tissues
103
function of venules
start of the collecting (drainage system)
104
what is a specialised feature of veins
they have spare capacity so can hold extra blood which pools in legs due to gravity
105
what layer of the vein is the thickest
adventitia
106
varicose veins are
when the valves stop working properly and blood can drop all the way back down to your feet.
107
the river to lake analogy refers to
arterioles to capillary
108
the diameter of a capillary is the same size as
a red blood cell
109
the almost identical diameter sizes in RBCs and capillaries allows for
the shortest gas exchange optimising this
110
the terminal arteriole is
the last arteriole before hitting a capillary bed
111
the post capillary venule
drains the capillary bed
112
pre capillary sphincters can
constrict and stop flow into capillary bed but go straight through the post capillary bed this is called shunting
113
the structure of capillaries
varies according to the rate of exchange needed, and how controlled the exchange must be
114
the most common type of capillary is
continuous
115
epithelial of continuous capillaries
form a complete barrier
116
small molecules can move through
fenestrated capillaries
117
all molecules smaller than RBCs can pass through gaps in
sinusoidal capillaries
118
layers of capillary outermost to innermost
basement membrane, endothelial layer (tunica intima), intercellular cleft
119
continuous capillaries are found
in skeletal and cardiac muscle
120
fenestrated capillaries are found
in glomerulus in kidney and small intestine
121
sinusoidal capillaries are found in
the liver
122
sinusoidal capillaries have an incomplete
basement membrane and interceullar gaps in intercellular cleft
123
functions of the lymphatic system
drains excess tissue fluid and plasma proteins from tissues and returns them to the blood. it also filters foreign material.
124
structure of lymphatics
commence as large, blind ending capillaries
125
function of lacteals
drain fat-laden lymph into a collecting vessel called the cisterna chyli
126
left hand side of the body and the lower body lymph fluid is drained
into the thoracic duct and then into the left subclavian vein
127
right hand side of the body is drained into
the right lymphatic duct and drains into the right subclavian vein
128
both the left and right subclavian veins join into which structure
vena cava
129
only on directional flow along the pathway
afferent to efferent
130
blood flow in the body is
deoxygenated into right atrium into right ventricle through lungs to oxygenate it back through the left atrium into the left ventricle through to all other organs
131
actin
thin filament
132
myosin
thick filament
133
with an increased force of cardiac contraction
an increase of cytosolic Ca2+ results in an increase of cross bridges formed and therefore an increase in force
134
diastole is
the relaxation, falling pressure
135
systole is
the contraction, rising pressure
136
first stage of the cardiac cycle
heart has been relaxed and is full of blood. atrial systole occurs, left and right atria contract, AV valves open.
137
second stage of cardiac cycle
atrial diastole (relaxation of atria). AV valves have closed. ventricles are contracting in isovolumetric ventricle contraction phase. both Av and semilunar valves are closed.
138
third stage of cardiac cycle
ejection phase, ventricles are squeezing so semilunar valves open, not all the blood leaves (ejection fraction).
139
ejection fraction is
the percentage of the blood being ejected from the heart during each beat
140
fourth stage in the cardiac cycle
semilunar valves shut as pressure in ventricles is low. AV valves are still shut. Ventricles relax (isovolumetric ventricular relaxation phase).
141
fifth stage of cardiac cycle
passive filling phase is where the veins fill the atria and ventricles with blood again
142
blood pressure is taken from the ___ circuit
systemic
143
blood pressure=
systole/ diastole pressure
144
mean pressure is
the average pressure across both cycles
145
hypotension
low blood pressure
146
hypertension
high blood pressure
147
haemodynamics
how blood flows in a single vessel
148
flow=
pressure difference/ resistance
149
Q=
change in P/ R
150
Description of electrical cells
pale, striated appearance- no striations. low actin and myosin
151
description of contractile cells
striated appearance, high actin and myosin
152
Depolarisation occurs at which node
Sinoatrial node
153
intercalated discs
connect most cells of the heart
154
function of intercalated discs and their gap junctions
the pores have low resistance to ionic current and allow current flow between adjacent cells
155
function of gap junctions
increase speed of the impulse through the heart, allow all the cells to behave as one
156
functional syncytium
millions of individuals cells working as one unit
157
is the brain needed to tell the heart to beat
no
158
function of AV node
pauses electrical signal so ventricle only contracts when atria has relaxed
159
depolarization
electrical signal arriving at some part of the heart telling the heart to contract
160
repolarization
electrical signal leaving the part of the heart telling it to relax
161
what is the lead in an ECG
virtual line between to surface electrodes
162
function of a single lead
detects a difference between electrodes (depolarisation and repolarisation)
163
P wave
depolarisation of the atria
164
QRS complex
atria repolarizing and AV node sending a signal to the ventricles to depolarize
165
T wave
depolarization of ventricles
166
the 'lubb' sound of the heart refers to what shutting
AV valves
167
the 'dubb' sound of the heart refers to what shutting
semilunar valves
168
in MAP the highest peak is
systolic pressure
169
in MAP the lowest valley is
diastolic pressure
170
arterial blood volume and pressure are determined by
balance between blood flow in and out
171
Mean arterial blood pressure=
cardiac output x total peripheral resistance
172
MAP=
CO x TPR
173
Cardiac output=
stroke volume x heart rate
174
CO=
SV x HR
175
stroke volume is
contraction strength
176
heart rate is
contraction speed
177
VO2 max is
peak performance
178
afferent input
to brain from body
179
efferent output
from brain to body
180
baroreceptors
blood pressure sensors and sense stretch within the aortic arch and carotid artery
181
parasympathetic pathway is
brake- rest and digest so great output is low
182
sympathetic pathway is
accelerator- fight or flight so need for great output is high
183
during exercise an increase of blood flow goes to
muscles, heart and skin
184
during exercise a decrease of blood flow goes to
GI tract and kidneys
185
during exercise a constant blood flow goes to
the brain
186
increased flow=
decreased resistance
187
decreased flow=
increased resistance
188
the rule of 16
cut a vessel diameter in half then resistance increased 16 times
189
R=
1/r4
190
vasoconstriction
the narrowing of the lumen to allow for less blood flow
191
vasodilation
the widening of lumen to allow for a greater blood flow
192
compliance
the extent to which a vessel allows deformation in response to an applied force
193
compliance=
change in volume/ change in pressure
194
what vessel is more compliant
veins
195
what counteracts venous pooling
surrounding muscle tone stiffens veins and valves prevent backflow of blood
196
starling's law of the heart
the more stretched muscle fibres are before a contraction the stronger the contraction will be
197
functions of the blood
transport, immune response and coagulation
198
what does blood transport
o2, water, nutrients, co2, waste products, ions , hormones and immune cells
199
coagulation factors include
platelets and factors in plasma
200
function of coagulation
preventing bleeding
201
haematopoiesis
the formation of blood cells
202
hemocytoblasts
progenitors for all blood cells
203
haematopoiesis occurs
in the red bone marrow
204
erythropoietin
make hemocytoblasts differentiate into red blood cells
205
function of the biconcave disc
large surface area to volume ration and allows for efficient diffusion of gases
206
Haemocrit or packed cell volume
the fraction of blood occupied by the red cells
