cv system Flashcards
CV SYSTEM
What are the 3 functions
PROTECTION: against infection Wbc
TRANSPORT: hormone, co2 o2 fuel
MAINTENANCE: body temp
CV SYSTEM
what are the 3 components of the circulatory system
BLOOD
BLOOD VESSELS
THE HEART
CV SYSTEM
describe the location of the heart
(4)
thoracic cavity
anterior of chest
posterior to sternum
between lungs
CV SYSTEM
what system does the
1) right atrium
2) left atrium
receive blood from?
1) systemic circuit
2) pulmonary circuit
CV SYSTEM
what system does the
1) left ventricle
2) right ventricle
pump blood into?
1) pulmonary circuit
2) systemic circuit
CV SYSTEM
what are the 3 layers of the heart wall (outside to inside
) ?
1) pericardium
2) myocardium
3) endocardium
CV SYSTEM
pericardium
fibrous tissue
stabilise heart
lubricate , pericardial fluid
CV SYSTEM
myocardium
thick muscle
Y shape, branched
large central nucleus
lots of mitochondria
myogenic, involuntary
intercalated discs
CV SYSTEM
intercalated discs
what are they
2 components
junctions between cells
GAP JUNCTIONS - depolarisation pass between cells
DESMOSOMES - bind adjacent myocytes
CV SYSTEM
endocardium
what does it cover
what is it made from
cover internal surfaces
- chambers, valves
epithelial tissue
CV SYSTEM
pathway of deoxygenated blood
vena cava
right atrium
tricuspid valve
right ventricle
pulmonary valve
pulmonary artery
CV SYSTEM
pathway of oxygenated blood
pulmonary vein
left atrium
bicuspid valve
left ventricle
aortic valve
aorta
CV SYSTEM
name 2 differences between the LV and RV
LV = thick , cylindrical
RV = thin, pouch shape
CV SYSTEM
what are the 2 types of cardiac muscle cells
CONTRACTILE : produce contraction
CARDIAC PACEMAKER CELLS : nodal / conducting
CV SYSTEM
electrical journey of heart
(4)
- SA NODE (pacemaker)
- AV NODE
- AV BUNDLE (bundle of his)
- PURKINJE FIBRES
CV SYSTEM
factors that change HR (4)
- autonomic nervous system
- catecholamines
- change in o2 / co2 levels
- change in BP
CV SYSTEM
what does
1) sympathetic nervous system
2) parasympathetic nervous system
do to hr
1) increase HR
2) slow HR
CV SYSTEM - catecholamines
ADRENALINE (epinephrine)
released by adrenal medulla
increase hr
by binding to adrenergic receptors
CV SYSTEM - catecholamines
NORADRENALINE ( Noraphinephrine)
initially increase hr , long term decrease
bind to heart adrenergic receptors
CV SYSTEM
Summarise the 6 stages of the cardiac cycle
1) ATRIAL SYSTOLE begin
blood into ventricle
2) ATRIAL SYSTOLE END, ATRIAL DIASTOLE BEGIN
3) VENTRICULAR SYSTOLE 1
pressure close AV valves
4) VENTRICULAR SYSTOLE 2
semilunar valve open , blood out
5) VENTIRCULAR DIASTOLE early
blood into atria
6) VENTRICULAR DIASTOLE late
chambers close and fill
CV SYSTEM
list the 3 categories of circulatory vessels
arterial system
venous system
capillaries
CV SYSTEM
arterial system
2 components
what does this system do?
arteries
arterioles
blood away from heart
CV SYSTEM
what is the arteriovenous anastomosis
low resistance pathway
bypass capillary bed
used for rapid control of blood e.g: reduce body temp quickly
CV SYSTEM
blood flow pathway through circulation
heart
artery
capillary
venule
vein
heart
CV SYSTEM
what system is there lower pressure in
systemic venous
CV SYSTEM
what are the 3 layers in a blood vessel?
tunica intima
tunica media
tunica externa
CV SYSTEM
tunica intima (inside layer)
- endothelial lining
- connective tissue lining
- internal elastic membrane
CV SYSTEM
endothelium
release vasoactive substance
effect vascular tone, bp, blood flow
maintain vascular homeostasis
CV SYSTEM
tunica media (middle)
concentric sheet of smooth muscle in loose connective tissue
around endothelium
bind to inner and outer layers
CV SYSTEM
what separates tunica media and tunica external
external elastic membrane (arteries)
CV SYSTEM
tunica externa (outer layer)
anchor vessel to adjacent tissue
contains:
- collagen fibres
- elastic fibres
- smooth muscle cell (in veins)
CV SYSTEM
what is the term for ‘vessels of vessels’
vaso vasorum
small arteries/veins in large arteries/veins
CV SYSTEM
artery wall
intima
media
externa
round thick wall
I: rippled , internal elastic membrane
M: thick, smooth muscle, elastic fibre
external elastic mem
E: collagen + elastic fibres
CV SYSTEM
vein wall
flattened, collapsed, thin
I: smooth, NO internal elastic mem
M: thin, smooth muscle, collagen fibres, NO external mem
E: collagen , elastic fibres
CV SYSTEM
what are the 3 types of artery?
elastic artery
muscular artery
arterioles
CV SYSTEM
ELASTIC ARTERY
2 examples
AORTA - high elastic in tunica media
CONDUCTING ARTERY - secondary pump
CV SYSTEM
MUSCULAR ARTERY
what does tunica media consist of
what does lower limbs have more of
tunica media = smooth muscle
smooth muscle, less elastin, greater vasoconstriction/dilation
CV SYSTEM
ARTERIOLE
smooth muscle
CV SYSTEM
CAPILLARIES
endothelial tube in thin basement membrane
no tunica media
no tunica externa
CV SYSTEM
what are the 3 types of capillary
continuous, fenestrated sinusoid
CV SYSTEM
CONTINUOUS CAPILLARY
where?
structure?
all tissues except epithelia + cartilage
complete endothelial lining
diffuse h20, small solute, lipid sol materials
CV SYSTEM
example of specialised continuous capillary
blood brain barrier in CNS
CV SYSTEM
FENESTRATED CAPILLARY
structure?
function?
where?
pore in endothelial lining
rapid exchange of h20 + large solutes
chloride plexus
endocrine organs
kidneys
intestinal tract
CV SYSTEM
SINUSOID
gap between adjacent endothelial cells
exchange h20 + large plasma proteins
in: liver, spleen , bone marrow, endocrine organs
CV SYSTEM
what cells monitor blood at sinusoids?
phagocytic cells
CV SYSTEM
capillary beds
aka _________ _____
capillary plexus
connect one arteriole + one venue
CV SYSTEM
pre capillary sphincter
guard entrance to capillary
open + closes , blood in pulses
CV SYSTEM
thoroughfare channels (capillary)
direct capillary connection from arteriole to venue
CV SYSTEM
3 types of vein
venule (small)
medium sized vein
large vein
CV SYSTEM
venue
tunica externa
endothelium
CV SYSTEM
medium sized veins
??????
CV SYSTEM
large veins
??????
CV SYSTEM
venous valves
folds in tunica intima
prevent back flow
CV SYSTEM
what structure helps veins get blood back to heart
skeletal muscle pump
CV SYSTEM
VEINS
blood from capillaries back to heart
large diameter, thin walls, lower bp
smooth muscle = autonomic , control blood flow + pressure
CV SYSTEM
blood flow
cardiac output
CV SYSTEM
pressure
pressure gradient
P = generated by heart to overcome resistance
pressure gradient = difference in P from one end of vessel to other
CV SYSTEM
flow (F) calculation
pressure gradient / resistance
CV SYSTEM
circulatory pressure must overcome _______ ____________ _______
what is this effected by (3)
total peripheral resistance
1.vascular resistance
2. blood viscosity
3. turbulence (swirling in chambers)
CV SYSTEM
what is vascular resistance
what is it effected by
friction between blood + vessel walls
vessel length / diameter
CV SYSTEM
as vessel diameter decreases what happens to R?
increases
CV SYSTEM
1) hypertension
2) hypotension
1) abnormally HIGH BP
2) abnormally LOW bp
CV SYSTEM
cardiovascular response to exercise (4)
increase HR
Increase Q
increase systolic BP
redistribution of blood flow
CV SYSTEM - regulate HR
1) parasympathetic nervous system …
2) sympathetic nervous system…
1) slow HR, vagus nerve, inhibit SA/AV node
2) increase HR, stimulate SA/AV node, cardiac accelerator nerves
CV SYSTEM
why does HR initially increase at start of exercise
later increase because …
parasympathetic withdrawal
increased SNS stimulation
CV SYSTEM
2 ways stroke volume changes
1) increase sympathetic nervous system
- circulate adrenaline/noradrenaline
2) increased end diastolic vol, increase stretch of sarcomeres, increase force of contraction
CV SYSTEM
what is : EDV
The Frank Starling Mechanism
“force of contraction is proportional to fibre length”
CV SYSTEM
cardiac output increases due to:
- increase hr
- increase sv
