WEEK 2 Flashcards
WHAT Two sounds are associated with closing of heart valves?
First sound (LUB ~ S1) AND Second sound (DUB ~ S2)
when does First sound (LUB ~ S1) occur?
occurs as atrioventricular valves close
what does First sound (LUB ~ S1) signify?
signifies the beginning of systole (ventricles contracting and pumping blood)
auscultation points of First sound (LUB ~ S1)
auscultation points are between the left 5th and 6th ribs (L)
when does Second sound (DUB ~ S2) occur?
occurs when semilunar valves close at the beginning of ventricular diastole (relaxed and filling with blood)
auscultation points of Second sound (DUB ~ S2)
auscultation points are between 2nd and 3rd ribs (L & R)
Arteries functions
carry blood away from the heart
branch and diverge as they form smaller vessels
carry oxygenated blood (except for pulmonary arteries- which carry deoxygenated blood)
blood flow order of arterioles, capillaries and arteries.
arteries —>arterioles —>capillaries
Veins function
carry blood toward the heart
join, merge and converge into larger vessels
have valves
carry deoxygenated blood(except for pulmonary veins (which carry oxygenated blood)
blood flow order for veins, capillaries, venules
capillaries—>venules—>veins
Three main layers found in all arteries
Tunica Intima/Interna (innermost layer), Tunica Media (middle layer), Tunica Externa (outermost layer)
Tunica Intima/Interna (innermost layer) Contacts ….
Contacts the vessel lumen
Tunica Intima/Interna (innermost layer) consists of
consists of endothelium (↓fluid friction)
the basement membrane and the internal elastic lamina
what is Tunica Media (middle layer) innervated by?
Innervated by the sympathetic nervous system – e.g. ↑ stim. = vasoconstriction and ↓ stim. = vasodilation (due to the recoil of the wall)
what does Tunica Media (middle layer) consist of?
consists of a muscular layer and external elastic lamina
what does Tunica Externa (outermost layer) consist of?
connective tissue.
larger arteries contain vasa vasorum (small blood vessels that supply tunica externa) contain nerves which pass to the tunica media
Tunica Externa (outermost layer) provides
provides anchorage and protection
what artery is the closest to the heart?
Elastic artery
functions of Elastic artery:
delivers blood to regions
largest lumen diameter (~ low resistance)
more elastic
act as pressure reservoirs: expand and recoil as blood is ejected from the heart blood flows smoothly rather than in a pulsatile manner.
Elastic artery examples
e.g. Aorta, Pulmonary trunk, etc.
Muscular Artery delivers
delivers blood to organs
Muscular Artery consists of
more smooth muscle in tunica media (which means more active in vasoconstriction and less distensible)
Muscular Artery examples
e.g. brachial arteries, radial arteries, femoral arteries, etc
Arteriole delivers
delivers blood to tissues
Arteriole consists of
very small lumen
what determines Arteriole’s blood flow to capillaries
arteriole diameter determines blood flow to capillaries (constriction causes tissues to be by-passed (shunting) and dilation increase flow to capillary bed)
Arteriole examples
e.g. kidney arterioles, brain arterioles, pulmonary arterioles, etc.
Capillaries are
the smallest blood vessels
capillaries deliver
deliver blood to tissues and cells
lumen is just big enough for a
single erythrocyte to pass along
Capillaries consists of
consists of a single layer of tunica intima (endothelium and basement membrane), which does not contain smooth muscle
most tissues have a rich capillary supply except for…
most tissues have a rich capillary supply (except for tendons, ligaments, cartilage and epithelium)
main function of capillaries
main function is to exchange O2, CO2, nutrients, hormones, etc., between blood and interstitial fluid
types of Capillaries
3 structurally different types: continuous, fenestrated and sinusoidal
Continuous capilaries are
most common and least permeable
Continuous capilaries are abundant in
skin and muscles
endothelial cells provide an uninterrupted (“continuous”) lining for
Continuous capilaries
in continuous capilaries there are tight…
tight junctions between cells
small gaps called intercellular clefts which allow limited passage of fluids and small solutes
…….. are more permeable than continuous capillaries
Fenestrated capillaries
endothelial cells contain
endothelial cells contain fenestrations (pores)
Fenestrated capillaries are found…..
found wherever active capillary absorption or filtrate formation occurs such as; small intestine ~ nutrients, endocrine organs ~ hormones into bloodstream and kidneys ~ filtration of blood(pores are constantly open.
Sinusoidal capillaries is the most …
permeable and has modified, leaky capillaries
Sinusoidal capillaries lumen shape
large, irregular-shaped lumens
in sinusoidal capillaries endothelial cells contain….
endothelial cells: contain large fenestrations (pores), have fewer tight junctions and have larger intercellular clefts
Sinusoidal capillaries allows for….
large molecules and RBCs to pass through
Sinusoidal capillaries are found….
only in the: liver, bone marrow, spleen, adrenal medulla
what are capillary beds?
Capillaries do not function independently they form networks called capillary beds
what is microcirculation
The flow of blood from an arteriole to a venule is called the microcirculation
Sinusoidal capillaries Consists of two types of vessels
Consist of two types of vessels: vascular shunt/meta-arteriole: directly connects the arteriole and venule. AND true capillaries: where the exchange actually takes place.
Blood flow in Sinusoidal capillaries is regulated by…
Blood flow is regulated by pre-capillary sphincters
what is Capillary exchange
Capillary exchange is the movement of fluid and dissolved materials in and out of a capillary
The capillary wall is …..membrane meaning….
The capillary wall serves as a semipermeable membrane –> does not allow blood cells and plasma proteins to move through (selectivity based on size of particles)
3 Layers of the capillary wall:
endothelial cells for lipid soluble substances: substances pass directly through the endothelial cells, includes; respiratory gases, alcohol, amino acids, sugars, etc
fenestrations (pores) in endothelial cells in fenestrated capillaries for larger and water soluble substance
intercellular clefts between endothelial cells for water soluble substances
why cant capillary exchange occur through simple diffusion
While capillary exchange could occur through simple diffusion (movement down a concentration gradient), this process would be very slow. Instead, fluid is forced to move in and out of the capillaries (carrying dissolved substances) – this transport mechanism is called bulk flow
what is Bulk flow
Bulk flow occurs in response to action of opposing forces (pressures)
Two steps in bulk flow: – filtration of fluid through the capillary walls into the interstitial space and – reabsorption of fluid into the capillary blood.
what is Filtration in bulk flow
Filtration is a selective movement of material into interstitial fluid through the capillary walls, that acts as a filter, it is directed outwards – promoted by blood hydrostatic pressure (the force exerted by a fluid pressing against a capillary wall)
what is reabsorption in bulk flow
Reabsorption is movement of material from interstitial fluid into capillaries – directed inwards. Promoted by blood colloid osmotic pressure (the force opposing hydrostatic pressure, contributed by proteins that cannot move through the capillary wall, such molecules are close to the capillary and draw water towards themselves).
Difference between blood hydrostatic pressure and blood colloid osmotic pressure is
Difference between blood hydrostatic pressure and blood colloid osmotic pressure is filtration pressure – it determines if fluid is moving from capillaries into interstitial space or in the opposite direction.
How do the pressures drive fluid flow across a capillary?
Net filtration occurs at the arteriolar end of a capillary
lymphatic system role in fluids
During capillary exchange a large amount of fluid move out into the interstitial space
The lymphatic system functions to reabsorb the fluids which have leaked into interstitial spaces (spaces between cells) and return it to blood circulation
Three main layers are found in all veins
Tunica Intima/Interna (innermost layer): contacts the vessel lumen, consists of endothelium (↓ fluid friction) and basement membrane, contain valves (except for venules)
Tunica Media (middle layer): innervated by the sympathetic nervous system, e.g. ↑ stim. = venoconstriction ↓ stim. = venodilation (due to the recoil of the wall), consists of a muscular layer
Tunica Externa (outermost layer): connective tissue, provides anchorage and protection, larger veins contain vasa vasorum (small blood vessels that supply tunica externa), contain nerves which pass to the tunica media
when are Venules formed
formed when capillaries unite
venule lumens
very small lumens
venules are extremely …
extremely porous (more like capillaries than veins), fluid and leukocytes (WBCs) move in and out easily
venules example
e.g. kidney venules, brain venules, pulmonary venules, etc.
Vein (medium) formed when
Vein (medium)
formed when venules unite
vein (medium) lumens
large lumens
Vein (medium) function/role
accommodate large blood volume
under lower pressure than arteries
Vein (medium) possess
possess venous valves (folds of tunica intima), most abundant in the veins of the limbs, where upward flow is opposed by gravity
outer and middle layer of vein medium
thick tunica externa
thin tunica media
vein (medium) etc.
e.g. cephalic vein, saphenous vein, et
Vein (large) formed when
Vein (large) formed when medium sized veins unite
vein (large) lumens
large lumens
Vein (large) function/role
accommodate large blood volume
under lower pressure than arteries
parts of Vein (large)
thin tunica media
thick tunica externa, with vasa vasorum and nerve
examples of vein(large)
e.g. superior and inferior vena cava, portal vein, etc.
In fluid dynamics, fluid flows due to
differences in pressure between two points (pressure gradient)
pumping of the heart during systole
The pumping of the heart generates pressure intermittently during systole. Therefore, blood is forced out of heart (higher pressure) into the arteries (lower pressure)
Elastic arteries function during systole and diastole
Elastic arteries expand during systole and recoil during diastole (due to abundance of elastic tissue). Lessens fluctuations in blood pressure, maintains steady flow of blood throughout cardiac cycle and decreases stress on small arteries
which parts have have large portion of smooth muscle and why?
Muscular arteries and arterioles have large portion of smooth muscle. Control flow into capillary network via vasoconstriction and vasodilation.
Blood flow is ….
Blood flow is the volume of blood flowing through a vessel, an organ, or entire circulation in a given period
Blood flow (F) is enabled and opposed by ….
Blood flow (F) is enabled by blood pressure and is opposed by peripheral resistance (amount of friction the blood encounters)
blood flow formula
Three important sources of resistance:
- blood viscosity (“thickness” of the blood due to formed elements and plasma proteins), -total blood vessel length (depends on body weight, increased in obesity; the longer the vessel, the greater the resistance) and
-blood vessel diameter (the most important and variable factor; the wider the vessel the lower the resistance).
Supporting mechanisms of venous blood flow;
skeletal muscle pump and respiratory pump
how does skeletal muscle pump Support venous blood flow?
skeletal muscle pump: contraction of muscles exerts pressure on veins and valves direct blood towards the heart; normally no back flow
how does respiratory muscle pump Support venous blood flow?
respiratory pump: decreased thoracic pressure during inhalation draws blood into thoracic veins and the right atrium
what is Systemic Blood Pressure
The pumping action of the heart generates blood pressure (measured in millimetres of Mercury [mm Hg]) and blood flow
Systemic blood pressure is highest in…. and declines ……
Systemic blood pressure is highest in the aorta and declines throughout the pathway (is 0mm Hg in the right atrium). Blood pressure near the heart is pulsatile. The steepest drop occurs in arterioles (resistance vessels)
Systolic pressure is
Systolic pressure: pressure exerted during ventricular contraction
Diastolic pressure is
Diastolic pressure: lowest level of arterial pressure
Pulse pressure is
Pulse pressure: difference between systolic and diastolic pressure (e.g. Aorta ~ 120 – 80 = 40)
what is Mean arterial pressure (MAP)
pressure that propels the blood to the tissues; can be calculated as: MAP = diastolic pressure + 1/3 pulse pressure
Pulse pressure and MAP both decline ….
with increasing distance from the heart
Blood pressure depends on
Blood pressure depends on cardiac output and peripheral resistance (vasoconstriction ↑ pressure while vasodilation ↓ it)
relatively fast flow of blood (Hg) is…
Large pressure gradient (about 60 mm Hg) between Aorta and the arterioles, means relatively fast flow of blood
Venous Blood Pressure is
Venous Blood Pressure is Steady and changes little during the cardiac cycle
Venous Blood Pressure gradient..
Small pressure gradient (about 15 mm Hg) between venules and the terminal parts of the vena cavae, means relatively slow flow of venous blood.
Short-term neural and hormonal controls Counteract
Short-term neural and hormonal controls; Counteract fluctuations in blood pressure by altering peripheral resistance
Long-term renal regulation Counteracts
Long-term renal regulation; Counteracts fluctuations in blood pressure by altering blood volume
Neural controls of peripheral resistance:
maintain MAP by altering blood vessel diameter
alter blood distribution in response to specific demands (capillary sphincters)
operate via reflex arcs that involve; baroreceptors and/or chemoreceptors, (in carotid arteries and aortic arch), vasomotor centre in medulla/vasomotor fibres and vascular smooth muscle.
what are Baroreceptors
Baroreceptors: pressure-sensitive mechanoreceptors that respond to changes in arterial pressure and stretch. e.g. activation from ↑ aortic stretching –> vaso/venodilation to decrease BP
what are Chemoreceptors
Chemoreceptors: sensory receptors that respond to changes in CO2, H+ and O2. e.g. activation from increased CO2 in blood –>vasoconstriction to increase BP –> blood to lungs
vasomotor centre in medulla/vasomotor fibres and ….
Cardio-stimulatory centre and Cardio-inhibitory centre
vascular smooth muscle are
smooth muscle fibres in tunica media
Hormones influence blood pressure through their vasoactive effects or by regulating water balance:
Angiotensin II – potent vasoconstrictor, raises BP
Aldosterone – promotes Na+ and water retention by kidneys, increases blood volume and BP
Atrial Natriuretic Peptide (ANP) – increases urinary Na+ excretion, reduces blood volume and lowers BP
Anti-Diuretic Hormone (ADH) – promotes water retention and raises BP
how does Adrenaline and Noradrenaline (also known as epinephrine and norepinephrine) influence blood pressure through their vasoactive effects or by regulating water balance ?
Adrenaline and Noradrenaline (also known as epinephrine and norepinephrine)
exert effects on most blood vessels by binding to α-adrenergic receptors leading to vasoconstriction and increase in BP
however in skeletal and cardiac muscle blood vessels they binds to βadrenergic receptors causing vasodilation
Capillary. Endothelium
internally and basement
membrane externally
What is
microcirculation?
The flow of blood from an
arteriole to a venule
What is the
lymphatics systems
role in the
cardiovascular
system?
The lymphatic system
functions to absorb fluids
which have leaked from the
blood vessels to interstitial
spaces (spaces between
cells) and return it to blood
circulation.
Define: End Diastolic Volume, End Systolic
Volume and Stroke Volume
End Diastolic Volume: volume in ventricle at end of diastole
End Systolic Volume; volume in
ventricle at end of systole
stroke volume: volume ejected per
beat from each ventricle
Which 2 valves close during the first heart
sound (LUB)?
Tricuspid and bicuspid/mitral valve or Left and right atrioventricular valves
Systole = ventricular
___________
Diastole =
ventricular
___________
Contraction.
Relaxation.
What are the three
main layers of blood
vessels?
Tunica intima/interna,
Tunica Media and Tunica
Externa
what are Cardiocytes
the contractile cells of the heart,
however they are more complex than general muscle cells. Cardiocytes are muscle tissues that have a neural element.
What makes up one cardiocyte? List the
components and circle one cardiocyte on the
diagram
-Many sarcomeres (sarcomere is the
functional unit of a muscle
- 1 or 2 nuclei surrounded by glycogen
- many mitochondria
What connects a cardiocyte to another? What specialised mechanical junctions are
located here? What is their purpose? Label one on the diagram provided.
Intercalated discs. Desmosomes. To prevent cardiocytes from pulling apart.
What is the function of gap junctions? Label one on the diagram provided.
Allows ions
to flow between cells to spread action potentials. Allows the myocardium to act as
a single coordinated unit, functional syncytium
is cardiac muscle fatigue resistant?
Cardiac muscle depends almost exclusively on aerobic respiration to make ATP
needed for contraction. This means that cardiac muscle is fatigue resistant, as it does
not use anaerobic respiration
What does aerobic respiration mean?
Oxidation of organic compounds in a reaction
series that requires oxygen and produces ATP. Important: FUEL + O2 = Energy
(ATP)
Which organic fuels do cardiocytes use?
cardiocytes are adaptable to all organic
fuels but generally use fatty acids (60%), glucose (35%), lactic acid and amino acids
(5%)
Cardiac muscle is rich in ___, which a short-term source of stored oxygen
for aerobic respiration, and ____, which is stored energy. Cardiac muscle is
also rich in ___, it makes up 30% of cell volume and synthesizes __.
Cardiac muscle is rich in _MYOGLOBIN__, which a short-term source of stored oxygen
for aerobic respiration, and _GLYCOGEN___, which is stored energy. Cardiac muscle is
also rich in _MITOCHONDRIA__, it makes up 30% of cell volume and synthesizes ATP.
Due to reliance on aerobic respiration, what is cardiac muscle very vulnerable to?
Oxygen deficiency (hypoxia) which can cause myocardial infarction (heart attack).
Events of ECG.
- Atrial depolarization begins
- Atrial depolarization is complete
- Ventricular depolarization begins 4.Ventricular depolarization is complete
5.Ventricular repolarisation occurs
6.Ventricular repolarization is complete.
explain the events of step 1 of the ECG.
Atrial depolarization begins (wave of electrical activity
moving through atrial tissue towards AV node), causing
weak contraction of atrial tissue, moving blood from atria to
ventricles. AV valves are open, semilunar valves are closed.
Given there is “active” movement of electrical activity (ion
movement) in cardiac muscle cells, the ECG shows a blip of
electrical activity.
explain the events of step 2 of the ECG.
Atrial depolarization is complete, a slight delay in the
contraction of the ventricles means that residual blood in the
atria still has some time to drain into ventricles. AV valves
are still open, semilunar valves are still closed. Given there
is no “active” movement of electrical activity (ion movement)
in cardiac muscle cells, the ECG shows no electrical activity.
explain the events of step 3 of the ECG.
Ventricular depolarization begins (wave of electrical activity
moving through ventricular tissue towards apex and up the sides),
causing strong contraction of ventricular tissue, moving blood from
ventricles to pulmonary trunk and aorta. Atrial repolarisation occurs
(wave of electrical activity going in the opposite direction of
depolarisation as cells return to their electrical baseline). AV valves
are closed (which causes the first heart sound “LUB”), semilunar
valves are open. Given there is “active” movement of electrical
activity (ion movement) in cardiac muscle cells, the ECG shows a
blip of electrical activity
explain the events of step 4 of the ECG.
Ventricular depolarization is complete. AV valves are still
closed, semilunar valves are still open. Given there is no
“active” movement of electrical activity (ion movement) in
cardiac muscle cells, the ECG shows no electrical activity.
explain the events of step 5 of the ECG.
- Ventricular repolarisation occurs (wave of electrical
activity going in the opposite direction of depolarisation as
cells return to their electrical baseline). AV valves are now
open, semilunar valves are now closed (which causes the
second heart sound “DUB”). Given there is “active”
movement of electrical activity (ion movement) in cardiac
muscle cells, the ECG shows a blip of electrical activity.
explain the events of step 6 of the ECG.
- Ventricular repolarization is complete. AV valves are still
open, semilunar valves are still closed Given there is no
“active” movement of electrical activity (ion movement) in
cardiac muscle cells, the ECG shows no electrical activity.
Now the heart is ready for atrial depolarisation again!
First sound (LUB), Which two valves close:
Tricuspid and Bicuspid
Valves
Second sound (DUB), Which two valves close:
Pulmonary and Aortic
Semilunar Valves
First sound (LUB) Signifies the beginning
of:
systole
Second sound (DUB) Signifies the beginning
of:
Diastole
aortic valve location and timing of heart sound
during s2 in second intercostal space, right sternal border
tricuspid valve timing and location of heart sound
during S1 in fifth intercostal space, left sternal border
mitral valve timing and location of heart sound
S1 in fifth intercostal space, mid clavicular line.
pulmonary valve timing and location of heart sound
S2 in second intercostal space, left sternal border.
What is the simple equation that you can use to calculate how much blood is pumped
out of the heart (per ventricle) during one cardiac cycle?
SV = EDV – ESV
stroke volume = end diastolic volume - end systolic
stroke volume healthy range
The normal range is 50 to 100 ml.
what is Stroke volume
Stroke volume is the difference between end-diastolic and end-systolic volumes;
what happens if sv is too low and esv is too high?
SV is too low and ESV is too high. The cause could be an
increase in vascular resistance which prevents blood from being forced into the
vessels which could lead to decreases in oxygen rich blood from reaching extremities
tissue death gangrene, also could lead to a much higher heart rate as the heart
attempts to compensate for low SV.
What important things are
happening in the heart during the
QRS wave?
Ventricular
contraction, closing of the AV
valves (first heart sound),
opening of the aortic and
pulmonary valves
What are the three main layers of arteries and veins?
Tunica intima/interna, tunica media and tunica externa. Yes, there are differences. The
tunica intima/interma in veins possess valves which are not found in arteries. The
tunica media is much thicker in arteries compared to veins and the tunica externa is
thicker in veins than in arteries
Which layer is most responsible for vasoconstriction/dilation and
venoconstriction/dilation? Why
Tunica Media, it is innervated by the sympathetic
nervous system (fight/ flight).
Which type of arteries expand to lessen fluctuations in blood pressure?E
Elastic Arteries
Why are valves present in veins? What mechanisms assist the movement of blood
towards the heart?
Veins have valves to prevent blood from flowing backwards
and pooling, whereas arteries pump blood at higher pressures, which naturally
prevents backflow. Veins are under much lower pressure than arteries. Veins
need valves to keep blood flowing in one direction because the flow is less
constant. The movement of blood through veins is assisted by the respiratory
pump and the skeletal muscle pump
What are the three important sources of resistance? What can cause them?
1)blood viscosity (“thickness” of the blood due to formed elements and plasma
proteins)
2) total blood vessel length (depends on body weight, increased in obesity; the
longer the vessel, the greater the resistance)
3) blood vessel diameter (the most important and variable factor; the wider the
vessel the lower the resistance
what is Blood flow?
the volume of blood flowing through a vessel, an organ, or entire
circulation in a given period. Blood flow is enabled by blood pressure and is opposed
by peripheral resistance (amount of friction blood encounters).
what is bulk flow
Fluid carrying dissolved substances (oxygen, nutrients, wastes, etc.) are forced into and
out of capillaries
2 steps involved in bulk flow
there are two steps involved in bulk flow;
filtration of fluid and reabsorption of fluid.
what is filtration of fluid in bulk flow?
Filtration is a selective, outward movement of material into interstitial fluid through the
capillary walls, which acts as a filter.
What pressure promotes the filtration of fluid?
Blood hydrostatic pressure (the force
exerted by a fluid pressing against a capillary wall)
what is reabsorption of fluid?
Reabsorption is inward movement of material from interstitial fluid into capillaries
What pressure promotes the reabsorption of fluid?
Blood colloid osmotic pressure
(the force opposing hydrostatic pressure, contributed by proteins that cannot move
through the capillary wall, such molecules are close to the capillary and draw water
towards themselves)
What is the difference between these two pressures called? What does it determine?
Difference between blood hydrostatic pressure and blood colloid osmotic pressure
is filtration pressure – it determines if fluid is moving from capillaries into interstitial
space or in the opposite direction
Where does net filtration occur?
Arterial end of a capillary
Where does net reabsorption occur?
Venous end of a capillary
Name each capillary type and list some of their features
Define the term systolic pressure
pressure generated by ventricles
contracting to pump blood (maximum pressure)
Define the term diastolic pressure:
pressure generated by ventricles as they
relax (minimum pressure)
Define the term pulse pressure:
the difference between systolic pressure and diastolic pressure (e.g. Systolic pressure- diastolic pressure = pulse
pressure [120 – 80 = 40])
Define the term pulse pressure:
the difference between systolic pressure and diastolic pressure (e.g. Systolic pressure- diastolic pressure = pulse
pressure [120 – 80 = 40])
formula for the Mean Arterial Pressure
(MAP) a
MAP = diastolic pressure + 1/3 pulse pressure
formula for the Cardiac Output (CO) of an individual.
CO = HR (heart rate) x SV (stroke volume)
a:Inferior Vena Cava
b: Right Common Iliac Artery
c: Aorta/Thoracic Aorta
d: Left Renal Vein
e: Aorta/Abdominal Aorta
Which type of blood vessels expand to lessen fluctuations in blood pressure?
Elastic arteries
Where are sinusoidal capillaries located?
Liver, bone marrow, spleen and adrenal medulla.
a:Great Saphenous Vein
b:Great Saphenous Vein
c:Femoral Artery
Name the three main layers of a blood vessel, from deep to superficial.
Tunica Interna/Intima, Tunica Media and Tunica Externa
a: Radial Artery/Right Radial Artery
b:Brachial Artery/Right Brachial Artery
c:Ulnar Artery/Right Ulnar Artery
d:Basilic Vein /Right Basilic Vein
e: Median Cubital Vein/Right Median Cubital Vein
f:Cephalic Vein/Right Cephalic Vein
List the three main arteries that arise from the abdominal aorta which supply structures of the gut (foregut, midgut and hindgut), from superior to inferior.
Celiac Trunk, Superior Mesenteric Artery and Inferior Mesenteric Artery
a: Right Common Carotid Artery
b: Right Subclavian Artery
c: Left Common Carotid Artery
d: Left Brachiocephalic Vein
Select the most correct statement regarding superficial and deep veins.
Answers:
a.
The cephalic, great saphenous and basilic veins are deep veins.
The brachial, femoral and ulnar veins are superficial veins.
b.
The femoral, great saphenous and median cubital veins are superficial veins.
The brachial, femoral and ulnar veins are deep veins.
c.
The cephalic, great saphenous and basilic veins are superficial veins.
The brachial, femoral and ulnar veins are deep veins.
d.
The cephalic, lesser saphenous and basilic veins are superficial veins.
The brachial, median cubital and ulnar veins are deep veins.
c.
The cephalic, great saphenous and basilic veins are superficial veins.
The brachial, femoral and ulnar veins are deep veins.
Select the TWO supporting mechanisms of venous blood flow.
Selected Answers:
Answers:
a.
Respiratory and Contraction Pump
b.
Left Ventricle and Gravity Pump
c.
Skeletal Muscle and Contraction Pump
d.
Contraction Pump
e.
Respiratory and Skeletal Muscle Pump
Correct
Respiratory and Skeletal Muscle Pump
The __________ layer of arteries/veins is innervated by the __________ nervous system.
Answers:
Tunica Intima; Sympathetic
Tunica Media; Sympathetic
Tunica Intima; Parasympathetic
Tunica Externa; Somatic
Tunica Media; Parasympathetic
Tunica Media; Sympathetic
What are the three important sources of resistance that affect blood flow?
blood viscosity, total blood vessel length and blood vessel diameter
Neural controls of peripheral resistance operate via reflex arcs which involve:
baroreceptors and/or chemoreceptors, vasomotor centre in medulla/vasomotor fibres and vascular smooth muscle
For filtration to occur, ……
the hydrostatic pressure inside the capillary must be greater than the colloid osmostic pressure outside of the capillary.
Capillary exchange is the movement of fluid and dissolved materials in and out of a capillary. Capillary exchanges involves:
Filtration and Reabsorption of fluid
Select the FALSE statement regarding the Tunica Media of Blood Vessels
The tunica media contacts the vessel lumen in veins
In the cardiovascular system, what is the definition of hydrostatic pressure?
the force exerted by a fluid pressing against a capillary wall
For reabsorption to occur….
the colloid osmotic pressure of the capillary must be greater than the hydrostatic pressure inside the capillary.
Where are the largest group of baroreceptors located in the body and what do they detect?
Aortic Arch - changes in arterial pressure and stretch
draw a schematic diagram of a capillary bed
only one capillary is drawn on bottom but you can fill it in.
arteriole in capillary bed function
-it is on one side of the capillary bed, and it brings oxygenated blood towards the tissues.
venules in capillary bed function
venules are on other side and they drain deoxygenated blood, away from the tissues, and into the venous system
capillary exchange: what facilitates the movement of these gases between capillary and the interstitial fluid (fluid surrounding tissues)?
-o2 (as well as nutrients n hormones)in arteriole blood, which needs to get to tissues below it. tissues produce co2(as a waste product, which needs to go into the capillary to be taken into the venous system back into heart).
-we cant rely on passive movement of gases as it would take forever, instead we need to force these gases across the capillary membranes so either out or in.
-moving o2 out of arteriole is called filtration.
- heart is pushing blood through the arteries n eventually down to the arterioles, this creates pressure pushing outwards called blood hydrostatic pressure (BHP) (of the capillary). Thus, pressure that is exerted by blood itself, generated by heart.
-there is also pressure imposing it.colloid osmotic pressure (COP), of the capillary that is pulling water towards the capillary. COP is also on the inside, these 2 pressures push against each other, one of the pressures being greater than another allows for movement.
-if the pressure on the outside of capillary is greater than inside, youll have things moving in and vice versa. on the arteriole end there is a higher pressure from the inside (heart pressure and cop)
-cop is generated by small proteins that sit on edge of capillary, they have a pull towards them, which pulls water molecules towards them n therefore exerts pressure on wall of capillary.
-pressure on inside of arteriol wall is much greater than outside, therefore we have filtration in which o2 moves from the capillary down to the interstitial fluid to get to the tissues.
-moving co2 into venule is called reabsorption.
-as pressure moves through capillaries from hesrt and blood, its actually taken out. Because there is so much resistance in these vessels we have to lose a lot of blood hydrostatic pressure. when BHP is near venules the pressure isnt great anymore. The colloid osmotic pressure (cop) and hydrostatic pressure is still outside pushing on capillary wall, doesnt contribute much, but contributes something. Colloid osmotic pressure is also in inner wall. If we take the net filtration pressure, so the pressure hats on the outside compared to inside, now the pressure on the outside is greater.
-higher pressure will move things into lower pressure. this is what allows co2 n waste that need to get back into the venous system to get pushed into the capillary in a process known as reabsorption, so it can end up in venous system.
what are cardiocytes
heart tissue cells (pic of 1 cardiocyte)
what forms the the myocardium of the heart?
many cardiocytes joining together to form the myocardium of the heart
what makes up 1 cardiocyte?
- 1or many nuclei (in the middle of pic)
- nucleus surrounded by glycogen (short term source of energy)
- lots of mitochondria (lining in between fibres), able to produce energy
-sarcomeres; striated bands of muscle.functional bands of muscle.
Blood Pressure is controlled by:
a.
Long-term renal regulation
b.
Short-term neural controls
c.
Short-term hormonal controls
d.
All of the above
d
Select the FALSE statement regarding the conduction system of the heart.
a.
Purkinje fibres are specialised muscles cells that conduct signals quickly to the ventricular myocardium.
b.
The Sinoatrial Node is a specialised autorhythmic cell in the wall of the left atrium, which undergoes spontaneous depolarisation.
c.
The Atrioventricular Node is a cluster of specialised cells located in the interatrial septum, which transmits electrical signals after a slight delay, to the Atrioventricular Bundle (Bundle of His).
d.
The Atrioventricular Bundle (Bundle of His) connects the Atrioventricular Node and the ventricles. It divides into the left and right bundle branches for each ventricle.
b
Capillary exchange is the movement of fluid and dissolved materials in and out of a capillary. Capillary exchange involves:
a.
Reabsorption of excess fluid into the lymph vessels
b.
Filtration and Reabsorption of fluid
c.
Reabsorption of fluid
d.
Filtration of fluid
b
Which source of resistance in the cardiovascular system is the most variable in an individual?
a.
plasma viscosity
b.
blood viscosity
c.
total blood vessel length
d.
blood vessel diameter
d
Superior Mesenteric Artery; 2nd and 3rd part of small intestine, appendix, 1st part of large intestine, etc.
Select the FALSE statement regarding the Tunica Media of Blood Vessels
a.
The tunica media does not contact the vessel lumen in veins
b.
The tunica media is not innervated by the sympathetic nervous system in arteries
c.
The tunica media is a muscular layer
d.
The tunica media is thicker in arteries than in veins
a
Which answer correctly lists the flow of blood through the valves (starting at the right atrium)?
a.
tricuspid valve à pulmonary valve à bicuspid valve à aortic valve
b.
aortic valve à bicuspid valve à pulmonary valve à tricuspid valve
c.
bicuspid valve à pulmonary valve à tricuspid valve à aortic valve
d.
tricuspid valve à aortic valve à bicuspid valve à pulmoary valve
a
What are the main functions of blood?
The main functions of the blood to distribute nutrients, wastes, etc. around the body, regulate the internal environment of the body such as body temperature, fluid levels and pH, and to protect the body against infections and blood loss.
Which organic fuel is used most in the process of cardiac muscle aerobic respiration?
fatty acids
a. Right Common Carotid Artery
b. Right Subclavian Artery
c. Left Common Carotid Artery
d. Left Brachiocephalic Vein
a. Great Saphenous Vein
b. Great Saphenous Vein
c. Femoral Artery
Which type of blood vessels expand to lessen fluctuations in blood pressure?
elastic arteries
a. Inferior Vena Cava
b. Right Common Iliac Artery
c. Thoracic Aorta
d. Left Renal Vein
e. Abdominal Aorta
what the three main arteries that arise from the abdominal aorta which supply structures of the gut (foregut, midgut and hindgut), from superior to inferior.
Celiac Trunk, Superior Mesenteric Artery and Inferior Mesenteric Artery
Name the three main layers of a blood vessel, from deep to superficial.
Tunica Interna/Intima, Tunica Media and Tunica Externa
Where are sinusoidal capillaries located?
Liver, bone marrow, spleen and adrenal medulla.
a. Radial Artery
b. Brachial Artery
c. Ulnar Artery
d. Basilic Vein
e. Median Cubital Vein
f. Cephalic Vein
In the cardiovascular system, what is the definition of hydrostatic pressure?
the force exerted by a fluid pressing against a capillary wall
What are the three important sources of resistance that affect blood flow?
blood viscosity (“thickness” of the blood due to formed elements and plasma proteins)
total blood vessel length (depends on body weight, increased in obesity; the longer the vessel, the greater the resistance)
and blood vessel diameter (the most important and variable factor; the wider the vessel the lower the resistance)
For filtration to occur
the hydrostatic pressure inside the capillary must be greater than the colloid osmostic pressure outside of the capillary.
For reabsorption to occur,
the colloid osmotic pressure of the capillary must be greater than the hydrostatic pressure inside the capillary.
Where are the largest group of baroreceptors located in the body and what do they detect?
Aortic Arch - changes in arterial pressure and stretch
The __________ layer of arteries/veins is innervated by the __________ nervous system.
Tunica Media; Sympathetic
Neural controls of peripheral resistance operate via reflex arcs which involve:
baroreceptors and/or chemoreceptors, vasomotor centre in medulla/vasomotor fibres and vascular smooth muscle
Select the TWO supporting mechanisms of venous blood flow.
Respiratory and Skeletal Muscle Pump. The Respiratory Pump works by decreasing thoracic pressure during inhalation which draws blood into thoracic veins and the right atrium.
The Skeletal Muscle Pump works by the contraction of muscles exerting pressure on veins and valves which directs blood towards the heart.
Capillary exchange is the movement of fluid and dissolved materials in and out of a capillary. Capillary exchanges involves:
Filtration and Reabsorption of fluid
