103 terms

Chapter 11: The Cardiovascular System

notes from the anatomy powerpoints on the cardiovascular system.
cardiovascular system
a closed system of the heart and blood vessels; function is to deliver oxygen and nutrients (and hormones) and to remove carbon dioxide and other waste products
blood vessels
allow blood to circulate to all parts of the body; take blood to tissues and back
located in thorax between the lungs, pointed apex directed toward left hip, size of fist
double serous membrane of visceral and parietal layers; anchors heart to sternum/diaphragm
visceral pericardium
layer of pericardium that is next to the heart, connects to epicardium
parietal pericardium
outside layer of pericardium
serous fluid
fills the space between the layers of pericardium
condition: walls of pericardium stick together
outside layer of heart wall; connects to visceral pericardium; connective tissue layer
middle layer of heart wall; mostly cardiac muscle; layer that actually contracts
inner layer of heart wall; endolethium; continuous with blood vessels entering/leaving heart
receiving chambers of the heart; found on both left sides and right sides
discharging chambers of the heart; found on both left sides and right sides
interventricular septum
divides left and right side of heart longitudinally
what color will is the right side?
what color is the left side?
allow blood to flow in only one direction; open as blood is pumped through; held in place by chordae tendineae; close to prevent backflow
atrioventricular valves (AV valves)
two valves between atria and ventricles on both sides; includes bicuspid and tricuspid valves; open when heart is relaxing and closed when heart is contracting
semilunar valves
two valves between ventricle and artery; includes pulmonary and aortic valves; closed when heart is relaxed, open when heart is contracting
chordae tendineae
"heart strings"; hold valves in place; close to prevent backflow
heart murmurs
condition: indicates valve problem; valve doesn't close tightly; if blood flow is turbulent and making extra sound (usually leaky valves) so Dr. hears blood rushing backward; valves can be replaced with pig valves if bad enough
valvular stenosis
condition: valve flaps become stiff (usually infection) and heart workload increases
largest artery of the body; leaves left ventricle and goes to body with oxygenated blood
pulmonary arteries
carry deoxygenated blood to lungs; leaves right ventricle
superior and inferior vena cava
two parts; enter right atrium
pulmonary veins
four parts; from lungs with oxygenated blood to enter left atrium
coronary veins
branch from base of aorta; give oxygenated blood to heart
cardiac veins
blood drained from heart through this into coronary sinus
coronary sinus
blood from heart's circulatory system empties into right atrium via this
angina pectoris
condition: chest pain with lack of oxygen (myocardium not getting enough blood)
myocardial infarction
"heart attack"; heart cells dying because of lack of oxygen
intrinsic conduction system (nodal system)
allows heart muscle cells contract, without nerve impulses, in a regular, continuous way
autonomic nervous system
controls the speeding up or slowing down of heart beat in conduction system
1 sinoatrial node
2 atrioventricular node
3 atrioventricular bundle
4 bundle branches
5 purkinje fibers
list: parts of conduction system
sinoartrial node
part of conduction system; highest rate of depolarization, starts each heartbeat/heart contraction (in right atrium); maintains heartbeat at 75x a minute (pacemaker for heart);
atrioventricular node
part of conduction system that delays impulse to give atria time to contract
atrioventricular bundle
part of conduction system within interventricular septum
conduction system
special tissues that set the pace of the heartbeat
.22 seconds
length of time for entire conduction system sequence to work
condition: irregular heart beat (uncoordinated atrial and ventricular contraction)
condition: out of phase contractions; heart is useless as pump
autorhythmic cells
sequential stimulation occurs here
lack of adequate blood to heart (injury to SA node sometimes)
acts as artificial SA
rapid heart rate (over 100 beats per min)
slow heart rate (lower than 60 beats per min)
contraction of ventricles
relaxation of ventricles
these contract simultaneously in a healthy heart
above term relax and this term contracts
ECG/EKG (electrocardiography)
method of mapping electrical activity of the heart- traces flow of current through heart
name/name (extended name)
3 electrical waves of an electriclam impulse through the heart
P wave
wave of atrial depolarization
QRS wave
wave of atrial repolarization and ventricular depolarization
T wave
wave of ventricular repolarization
cardiac cycle
events of one complete heart beat
mid-to-late diastole
part of heart beat when blood flows into ventricles from atria
ventricular systole
part of heart beat when blood pressure builds before ventricle contracts, pushing out blood
early diastole
atria finish re-filling, ventricular pressure i low
louder sound of heart beat; closing AV valves
quieter sound of heart beat; closing semilunar valves
blood pressure
pressure exerted on walls of arteries by blood (taken by sphygmomanometer); especially high number can cause heart attack, stroke, etc.
systolic pressure
maximum pressure in arteries when contracted
diastolic pressure
pressure at rest
cardiac output
amount of blood pumped by each side of the heart in one minute
CO = (heart rate [HR] in bpm) x (stroke volume [SV])
formula for cardiac output
stroke volume
volume of blood pumped by each ventricle in one contraction; usually remains constant
lungs - pulmonary veins (4) - LA- LV - Aorta - Body (systemic circuit) - exchanged at capillaries - inferior/superior vena cava - RA - RV - pulmonary arteries - lungs (pulmonary circuit
trace: blood flow in words, starting and ending with lungs
starling's law of the heart
rule that states that the more that the cardiac muscle is stretched, the stronger the contraction
1. sympathetic nervous system
2. hormones
3. exercise
4 decreased blood volume
four causes of increased heart rate
1. parasympathetic nervous system
2. high blood pressure or blood volume
3. excess/lack of Ca, Na, and K
three causes of decreased heart rate
congestive heart failure
condition: pumping efficiency of heart is inadequate to meet tissue needs
coronary atherosclerosis
condition: leads to congestive heart failure from clogging of coronary vessels with fatty buildup
age, gender, exercise, body temp, weight, time of day, body position, emotional state, drugs
list: environmental and genetic factors that affect heart rate
blood vessel that carries blood away from the heart; thickest walls because of maximum pressure of blood flow from heart
minute artery
minute blood vessel connecting arterioles with venules; walls only one cell thick to allow for exchange between blood and tissue; oxygen and nutrients cross to cells; carbon dioxide and metabolic waste products cross into blood
minute vein
blood vessel that carries blood away from tissues towards heart; lumens (open space) are largest to; lumens have valves to prevent backflow; use skeletal muscles to help move blood
arteries - arterioles - capillaries - venules - veins
trace: blood flow through blood vessels
tunic intima
most internal of blood vessel layers
part of tunic intima; decreases friction of blood flow
tunic media
bulky, middle layer of blood vessels; smooth muscle; controlled by sympathetic nervous system, which changes the diameter of blood vessels
tunic externa
outermost layer of blood vessels; mostly fibrous connective tissue to support and protect vessels
varicose veins
condition: pooling of blood in the feet/legs because of inefficient return from inactivity or pressure; common in people who stand a lot
hepatic portal circulation
drain blood from digestive organs, spleen, pancreas, and passes to liver which detoxifies before passing into systemic circulation
pressure wave of blood; expansion and recoil of an artery with beat of L ventrioles; average 70-76 bpm
"pressure points"
locations to monitor pulse; pulse is easily palpated
pulse, respiratory rate, and body temperature
3 vital signs
pressure at the peak of ventricular contraction
pressure when ventricles relax
neural factors
effects bp; autonomic nervous system adjustments (sympathetic division)
narrowing of blood vessels; raises bp
widening of blood vessels; lowers bp
renal factors
effects bp; regulation by altering blood volume; as viscosity (thickness) goes up, bp goes up; renin is hormonal control
peripheral resistance
amount of friction encountered by blood as it flows through blood vessels
heat has a ______ effect on blood vessels
cold has a _________ effect on blood vessels
condition: low systolic number for blood pressure; often associated with illness
condition: high systolic number for blood pressure; can be dangerous if chronic
capillary exchange
substances exchanged due to concentration gradients; oxygen and nutrients leave blood; carbon dioxide and other wastes leave cells; direct diffusion across plasma membrane; endocytosis or exocytosis
intercellular clefts
gaps in capillaries; plasma membrane not joined by tight junctions
pores in capillaries
when does a simple "tube heart" develop in embryo? (# of weeks)
when does the heart become a four-chambered organ? (# of weeks)