A&P II Practical #2
the force that blood exerts against the walls of the blood vessels
blood pressure is highest in these
The ventricles of the heart contract & eject blood into the aorta & pulmonary arteries
blood pressure is highest when
Systolic blood pressure
blood pressure measured during ventricular contraction (cardiac systole)
Diastolic blood pressure
blood pressure measured during ventricular relaxation (cardiac diastole)
Veins & Arteries
have the same number of layers
consists of an inflatable bladder enclosed in a nondistensible cuff
necessary for the auscultatory method of blood pressure measurement
arteries forming a network for multiple pathways for blood to flow
Circle of Willis & Coronary Circulation
examples of anastomosis
Superior vena cava & inferior vena cava
all of the body's systemic veins (except cardiac veins) drain where
endothelial tissue => connective tissue => elastic tissue
three layers of the tunica intima (deep to superficial)
Simple squamous epithelium; Lumen
the endothelium consists of ________ _________ __________ that forms a smooth inner lining around the ___________.
allows for the expansion of the arteries
thickest layer on the walls of large arteries
made up of elastic tissue in large arteries & smooth muscle in small arteries
made up of collagen and elastic tissue (& nerves, & small blood vessels)
thing that veins contain & arteries don't
the only blood vessel whose walls permit gas exchange between the blood & surrounding tissues
tunica media or tunica externa
capillaries contain no...
thickening & toughening of arterial walls due to loss of elasticity as aging occurs
a disease that occurs when fatty deposits form along the walls of arteries
a bulge in the weakened wall of a blood vessel, usually an artery
sagging & swollen vessels
high blood pressure (systolic > 140mmHg ; diastolic > 90mmHg)
circulation to all body parts minus lungs & heart
brings oxygenated blood & nutrients to the heart
Oxygenated => deoxygenated
systemic & coronary circulations start _______ & end __________.
brings deoxygenated blood to the lungs to be reoxygenated
Deoxygenated => Oxygenated
Pulmonary circulation starts _______ & ends ____________.
left side of the heart associated with...
right side of the heart associated with...
Superior vena cava
brings blood above the heart back to the right atrium
Inferior vena cava
brings blood below the heart back to the right atrium
heart attack due to death of tissue
atria ; ventricle
When the heart beats _______ contract first, followed by _______.
the left side of the heart has to pump blood out of the heart to the rest of the body whereas, the right side only has to pump blood to the lungs which are relatively close to the heart
Why is the left ventricle thicker than the right ventricle?
a thick wall that seperates the right & left ventricles
when valves close abnormally or there is a structural heart defect, blood can produce a gurgling or swishing sound
between the right atrium & right ventricle
pulmonary semilunar valve
between the right ventricle & pulmonary artery
between left atrium and left ventricle
aortic semilunar valve
between the left ventricle and the aorta
sound heard when AV valves close
sound heard when semilunar valves close
carry blood away from the heart
oxygenated blood in systemic circulation
deoxygenated blood in pulmonary circulation
carry blood to the heart
deoxygenated blood in systemic circulation
oxygenated blood in pulmonary circulation
largest artery in the body
Superior & inferior vena cava
largest veins in the body
bad or lousy cholesterol that can cause arterial plaques leading to atherosclerosis
good or heavenly cholesterol that does not cause circulatory problems
EKG or electrocardiography
voltmeter; reads the electrical activity of the heart to see if it is generated & conducting correctly
a record (tracing) of electrical activity between 2 electrodes; allow viewing of the hearts electrical activity in different planes
if electrical activity is not detected, a straight line is recorded
movement away from baseline in the positive (upward) or negative (downward) direction
indicates AV conduction time
indicates early ventricular repolarization
indicates ventricular depolarization (contraction of ventricles)
represents ventricular depolarization & repolarization
indicates ventricular repolarization
indicates atrial depolarization (contraction of atrium)
HR = 101-160 bpm
Rhythm = regular or irregular
HR = 40-59 bpm
Conduction = P-R normal or slightly prolonged at slower rates
Rhythm = regular or slightly irregular
HR = unattainable
P wave - may be present, but obscurred by ventricular waves
QRS - not apparent
Conduction - chaotic electrical activity
Rhythm - chaotic electrical activity
base of the aorta
Where do the coronaries begin?
where do the coronary veins dump deoxygenated blood into?
to carry oxygenated blood to the heart to provide it with oxygen & nutrients
what is the function of coronary vessels?
it receives deoxygenated blood from the superior vena cava, inferior vena cava, and the coronary sinus
What type of blood (deoxygenated or oxygenated) does the right atrium receive and from which 3 vessels?
it receives oxygenated blood from the left & right pulmonary veins
What type of blood (deoxygenated or oxygenated) does the left atrium receive and from what vessels?
the aorta transports what type of blood?
the pulmonary trunk transports what type of blood?
the aorta has more elasticity because it has to be able to withstand the large amounts of blood and pressure coming from the left ventricle
which vessel (aorta or pulmonary trunk) has more elasticity & why?
the AV valves consist of a bicuspid & a tricuspid valve which are held to the ventricular walls by the chordae tendinae; the semilunar valves are composed of 3 cusp valves & these are opened and closed based on pressure
list 2 major differences in structure when comparing AV valves & semilunar valves
to reduce friction during heart activity so the heart can beat in a relatively frictionless environment
what is the function of the fluid that fills the pericardial sac?
to enforce a one-way flow of blood through the heart chambers & prevent back flow into the atria when ventricles are contracting
what is the function of the valves found in the heart?
anchor the cusps of the valves to the ventricular walls
what is the role of the chordae tendineae ?
if the mitral valve does not close properly, which circulation is affected?
because that would cut off the functional blood supply to that nourishes the heart
why might a thrombus in the anterior descending branch of the left coronary artery cause sudden death?
skeletal muscle has long, cylindrical, multinucleated cells with obvious striations, wheres as cardiac muscle has cells that branch, are striated with 1 nucleus & come together at intercalated discs
how would you distinguish the structure of cardiac muscle from that of skeletal muscle?
intercalated discs allow for electrical connections between cells & it holds myocytes together so they do not pull apart when the heart contracts.
many mitochondria provide the energy required for contraction
what are the unique anatomical features or cardiac muscle & what are their functions?
SA node => AV node => Bundle of His => bundle branches => purkinje fibers
list the elements of the intrinsic conducting system in order, starting at the SA node
AV node; because it allows the atria to contract completely, ejecting all of their contents into the ventricles before the ventricles begin to contract
what structure in the transmission sequence is the impulse temporarily delayed? Why?
to act as the pacemaker. the SA node provides the stimulus for the contraction since its discharge has the highest rate (under normal circumstances the SA node will set the heart rate)
even though cardiac muscle has an inherent ability to beat, the nodal system play a critical role. What is it?
because our heart is in a greater demand when our body is under that kind of strain. the heart must beat faster & harder in order to deliver a larger amount of blood to the organs and muscles that are being used while running
why does the heart rate increase during running?
ventricular fibrillation; because blood passes from the atria into the ventricles with the help of gravity only a little remaining blood is needed to be pumped, whereas the ventricles are fighting against gravity so if the pump is fibrillating the body is not getting the blood it needs = fatal
which would be more serious, atrial or ventricular fibrillation? why?
insufficient supply of blood to the brain region or damage to the vasculature in a particular area of the brain which causes bleeding into the nervous tissue
occurs when a vessel bursts causing bleeding in a region of the cerebral cortex
when small clots that formed in other parts of the body occlude cerebral arteries & cut off blood supply to the cerebral cortex
narrowing or blockage of vasculature that results in oxygen deprivation to a specific part of the cerebral cortex.
first to branch off the aortic arch
supplies the stomach & spleen
superior mesenteric artery
supplies the small intestine
inferior mesenteric artery
supplies large intestine
hepatic portal vein
superior mesenteric vein & splenic vein join to form?
internal iliac arteries carry blood where?
external iliac arteries carry blood where?
jugular & subclavian veins join together to form what?
superior vena cava
right & left brachiocephalic veins join together to form what?
comes along the vertebral column & is an alternate pathway for the blood to get from the lower part of the body to the heart
artery: tunica media thick, tunica externa thin, open & circular lumen
vein: tunica media thin, tunica externa thick, somewhat collapsed lumen
structural difference between arteries & veins
valves are present in veins because blood flowing back from the heart is often against gravity, thus the valves ensure venous return equals cardiac output by preventing back flow
why are valves present in vein but not arteries?
skeletal muscle pumps to "milk" blood & pressure changes that occur in the thorax during breathing
name 2 events occurring within the body that aid in venous return
arteries are closer to the pumping action of the heart & must be able to expand as an increased volume of blood is pumped into them during systole & recoil passively as blood flows off into circulation during diastole. the walls have to be sufficiently strong to withstand the pressure fluctuations
why are the walls of the arteries proportionately thicker than those of the corresponding veins?
it is a protective device that provides alternate pathways for blood to reach brain tissue in case of arterial occlusion or impaired blood flow in the system
what is the function of the circle of Willis?
the arteries in the pulmonary circulation are similar to the structure of the systemic veins (tunica media thin & tunica externa thick). this allows the pulmonary arteries to create a low pressure bed in the lungs to permit gas exchange
how do the arteries of the pulmonary circulation differ structurally from systemic arteries? what condition is indicated by this anatomical difference?
digestive viscera, spleen, & pancreas
what is the source of blood in the hepatic portal system?
to ensure that the proper sugar, fatty acid, and amino acid concentrations are in the blood
why is blood carried to the liver before it enters the systemic circulation?
what organ serves as a respiratory/digestive/excretory organ for the fetus?
which pulse point has the greatest amplitude?
which pulse point has the least amplitude?
alternate contraction & relaxation of the myocardium and opening & closing of valves
what 2 factors promote the movement of blood through the heart?
alternating surges of pressure in an artery that occur with each contraction & relaxation of the left ventricle
artery palpated at the wrist
superficial temporal artery
artery palpated at the front of the ear
dorsalis pedis artery
artery palpated at the dorsum of the foot
common carotid artery
artery palpated at the side of the neck
what pressure point would you compress to help stop bleeding in the thigh?
what pressure point would you compress to help stop bleeding in the forearm?
what pressure point would you compress to help stop bleeding in the calf?
what pressure point would you compress to help stop bleeding in the thumb?
arterial bleeding would be bright red & spurting whereas, venous bleeding would be dark red & oozing
how could you tell by simple observation whether bleeding is arterial or venous?
what is the name of the instrument used to compress the artery & record pressure in the ausculatory method of determining blood pressure?
venous pressure is much lower than arterial pressure; because the veins are further removed from the pumping action of the heart
how do venous pressures compare to arterial pressures? why?
decrease blood pressure
what is the effect on blood pressure: increased diameter of the arterioles
increased blood pressure
what is the effect on blood pressure: increased blood viscosity
increase blood pressure
what is the effect on blood pressure: increased cardiac output
decreased blood pressure
what is the effect on blood pressure: hemorrhage
increased blood pressure
what is the effect on blood pressure: arteriosclerosis
increased blood pressure
what is the effect on blood pressure: increased pulse rate
increased blood pressure
what is the effect on blood pressure: cold temp
decreased blood pressure; because it would cause your vessels to dilate (vasodilation)
what is the effect on blood pressure: heat? Why?