anatomy and physiology chapter 18
_________ __________ valve located between left ventricle and aorta
aortic semilunar
receives blood from circuits
atria
heart valve that is located between the atria and ventricles
atrioventricular valve
2 major types of heart valves
atrioventricular valve semilunar valves
2 _____ _______ prevents backflow into atria when ventricles contract
atrioventricular valves
returns blood from the coronary veins
coronary sinus
posterinferior surface
left ventricle
projects into ventricular cavity
papillary muscles
What is the correct sequence of electrical current flow through the heart wall?
SA node, AV node, AV bundle, right and left bundle branches, subendocardial conducting network
_________ circuit is long, high friction circulation
Systemic
What conducts the impulses through the interventricular septum
bundle branches
both left and right ______ _______arise from base of aorta and supply arterial blood to heart
coronary arteries
Functional blood supply to heart shortest circulation in body delivered when heart is relaxed left ventricle receives most of coronary blood supply
coronary circulation
circular or spiral bundles of contractile cardiac muscle cells middle layer of the heart
myocardium
returns blood from body regions below the diaphragm
inferior vena cava
What node generates impulses generally
sinoatrial node (SA)
Freshly oxygenated blood is delivered to the __________ and then it passes into the __________ to be pumped to the entire body.
left atrium; left ventricle
The noncontractile cardiac muscle cells that initiate their own depolarization and cause depolarization of the rest of the heart are called ___________
pacemaker cells
anchors chordae tendineae that are attached to heart valves
papillary muscles
why does the pulmonary artery transmit blood to the lungs
for CO2 removal and O2 uploading
pumps blood through systemic circuit
left ventricle
During systemic circulation, blood leaves the __________.
left ventricle and flows directly to the aorta
When the mitral valve closes, it prevents the backflow of blood from the __________.
left ventricle to the left atrium
in mediastinum between 2nd and 5th intercostal space on superior surface of diaphragm 2/3 heart to left of midsternal line anterior to vertebral column, posterior to sternum
location of heart
Guided by powerful signaling molecules, the human heart develops from __________.
mesoderm (Primary germ layer that forms the skeleton and muscles of the body.)
Where is the SA node located?
right atrium
receives blood returning from systemic circuit
right atrium
From the perspective of blood returning from the systemic circuit, identify the correct sequence of blood flow through the chambers of the heart
right atrium, right ventricle, lungs, left atrium, left ventricle, aorta
supplies blood to the lateral right side of the myocardium
right marginal artery
Pumps blood through pulmonary circuit
right ventricle
most anterior surface
right ventricle
During pulmonary circulation, blood leaves the __________.
right ventricle and flows directly to the lungs
2 ______ ________ prevent backflow from major arteries back into ventricles
semilunar valves
heart valve located between ventricles and major arteries
semilunar valves
Irregular ridges of muscle on ventricular walls
trabeculae carneae
____ _____ made up of 3 cusps and lies between right atria and ventricle
tricuspid valve
The _________ nerve carries parasympathetic fibers to the SA node
vagus
3 layers of heart wall
1. Epicardium 2. Myocardium 3. Endocardium
remnant of foramen ovale of fetal heart
fossa ovalis
The contractile cardiac muscle fibers of the myocardium behave as a single, coordinated unit called a _______ _____________
functional syncytium
A doctor puts his stethoscope on a patient's chest over the location of the heart and hears an abnormal swishing sound. What condition is the best diagnosis for the patient's condition?
incompetent cardiac valve
Which of the following factors gives the myocardium its high resistance to fatigue a) the coronary circulation b) the very large # of mitochondria in the cytoplasm c) gap junctions d) the presence of intercalated discs
B
The vessels that carry O2 to the myocardium are called ___________
coronary arteries
______ ventricle walls are 3X thicker than _________
Left, Right
seperates atria
interatrial septum
the discharging chamber
ventricle
The trabeculae carneae are located in the __________________
ventricles
Thicker walls than atria actual pumps of heart
ventricles
parietal layer lines internal surface of fibrous pericardium visceral layer on external surface of heart
2 layers of serous pericardium
The cardiac cycle includes all of the following except _______ a)the number of times the heart beats in one minute b)the movement of impulse from the SA node to all regions of the heart wall c)the changes in blood volume in all chambers of the heart d)the changes in pressure gradients in all chambers of the heart
A
Which of the following statements is NOT true about the shape, position, and location of the heart a) The heart is enclosed in a double-layered sac called the pleural membrane b) approximately 2/3s of the heart is found to the left of the midline c) the heart is shaped like a cone with the base facing the right shoulder d) the heart is located between the lungs within the mediastinum
A
encircles junction of atria and ventricles
Coronary sulcus (atrioventricular groove)
What is a pressure gradient?
Difference in pressure (hydrostatic or osmotic) that drives movement of fluid.
4 pulmonary veins left atrium mitral bicuspid valve left ventricle aortic semilunar valves aorta systemic circulation
Left side of the heart
_____________ circuit is short, low pressure circulation
Pulmonary
superior and inferior vena cava coronary sinus right atrium tricuspid valve right ventricle pulmonary semilunar valve pulmonary trunk pulmonary arteries lungs
Right side of heart
The normal pacemaker of the heart is the
SA node
An enlarged R wave on an ECG would indicate __________.
an enlarged ventricle
supplies blood to the interventricular septum and anterior walls of both ventricles
anterior interventricular artery
Anterior position of interventricular septum
anterior interventricular sulcus
The coronary arteries arise from
aorta
The superior chambers of the heart are called the __________.
atria
the ____________ bundle connects the atria to the ventricles
atrioventricular
If the SA node becomes damaged and nonfunctional, what takes over
atrioventricular node
Appendages that increase atrial volume
auricles
Why can't cardiac muscle go into tetany?
because the absolute refractory period is almost as long as the contraction
made up of 2 cusps and lies between left atria and ventricle
bicuspid valve
___________ have an unstable resting potential that continually depolarizes, drifting slowly toward threshold
cardiac pacemaker cells
Anchors cardiac muscle fibers. Supports great vessels and valves. Limits spread of action potentials to specific paths.
cardiac skeleton
TINY WHITE COLLAGENIC CORDS CALLED THE _____ ANCHOR THE CUSPS OF THE AV VALVES TO THE VENTRICULAR WALLS
chordae tendineae
The ___________ are attached to the AV valve flaps
chordae tendineae
The lining of the heart chambers is called the
endocardium
intermost layer of heart; is continuous w/ endothelial lining of blood vessels
endocardium
visceral layer of serous pericardium
epicardium
Which is the correct sequence of layers in the heart wall starting with outer layer
epicardium, myocardium, endocardium
seperates ventricles
interventricular septum
Which of the following is not a role of the fibrous pericardium? a) it facilitates heart contraction b) it protects the heart c) it anchors the heart to surrounding structures d) it prevents the heart from overfilling with blood
it facilitates heart contraction
The interventricular septum forms a dividing wall between the
left and right ventricles
Into which chamber of the heart do the pulmonary veins deliver blood?
left atrium
receives blood returning from pulmonary circuit
left atrium
receives oxygenated blood from the lungs
left atrium
The structure just deep to the fibrous pericardium is the
parietal layer of the serous pericardium
double walled sac that encloses the heart
pericardium
runs to the apex of the heart
posterior interventricular artery
Landmark on posteroinferior surface
posterior interventricular sulcus
takes deoxygenated blood from the heart to the lungs
pulmonary artery
______ _______ valve located between right ventricle and pulmonary trunk
pulmonary semilunar
Receives deoxygenated blood from the body
right atrium
The inferior vena cave brings blood from lower regions of the body and empties into the
right atrium
The endocardium is composed of __________.
squamous epithelium
the _______ _____________ network depolarizes the contractile cells of both ventricles
subendocardial conducting
functions to protect, anchor heart to surrounding structures and prevent over filling
superficial fibrous pericardium
returns blood from body regions above the diaphragm
superior vena cava
3 veins that empty into the right atrium
superior vena cava, inferior vena cava, coronary sinus
cardiac output is _________________
the amount of blood pumped out of each ventricle in one minute
Which of the following structures is superficial to the heart wall and serves to protect the heart, anchor the heart and prevent the heart from overfilling? a) the fibrous pericardium b)the pericardial sac c) the parietal layer of serous pericardium d) the epicardium
the epicardium
What part of the heart is considered the systemic circuit pump?
the left ventricle
Which of the following valves is most often faulty in the heart a) the aortic semilunar valve b) the tricuspid valve c) the pulmonary semilunar valve d) the mitral or bicuspid valve
the mitral or bicuspid valve
If the mitral valve were insufficient, would you expect to hear the murmur (of blood flowing through the valve that should be closed) during ventricular systole or diastole?
the murmur of mitral insufficiency occurs during ventricular systole
The absolute refractory period refers to the time during which
the muscle cell will not respond to a stimulus of any strength