AP II Test 2
Card Set Information
AP II Test 2
This part of the heart is the point of maximal intensity.
Size, shape, and weight of heart.
Fist sized, hollow, cone-shaped, 250 to 350 grams
The heart is located in which cavity?
Thoracic medial cavity (mediastinum)
The heart rests on the superior surface of this.
These are located laterally to the heart.
A double-walled sac made of tough, dense connective tissue.
Three functions of the pericardium.
protects the heart
anchors it to surrounding structures
prevents overfilling of the heart with blood
Layers of the pericardium.
The three layers of the heart wall are rich in blood supply, connective tissue. The three layers are...
Part of heart wall that is part of the pericardial layer, top layer, has fat.
The middle heart wall layer, has cardiac muscle, involved in contraction, form crisscrossing tissue fibers and arranged in spiral of circular bundles.
Part of heart wall that is a sheet of squamous epithelium on a thin connective tissue layer.
This layer of the heart wall is located on the inner myocardial surface, lines the heart chambers, and covers the fibrous skeleton of the valves.
Four chamber of the heart.
L and R atrium
L and R ventricle
This seperates the atria longitudinally, L and R
This seperates the ventricles, L and R.
This ventricle forms most of the anterior surface of the heart.
this ventricle dominates the inferoposterior aspect of the heart ann forms the heart apex.
Small and thin-walled "receiving chambers" that push blood "downstairs", low pressure.
Blood enters the right atrium via these three veins.
superior vena cava
inferior vena cava
Four pulmonary veins enter which atrium, and transport blood from the lungs back to the heart?
These "discharging chambers" make up most of the volume of the heart.
These are irregular ridges of muscle that mark the internal walls of the ventricular chamber.
Cone-like muscles that play a role in valve function that project into the ventricular cavity.
The contraction of this ventricle propels blood out of the heart, via the aorta, and into circulation.
This ventricle pumps blood into the pulmonary trunk then to the lungs for gas exchange.
Circulatory system involving blood supply to and from all body tissues.
Circulatory system involving blood to and from the lungs for gas exchange.
Circulatory system involving blood supply to the myocardium.
Systemic circulation is a function of what side of the heart?
Path of blood in systemic circulation.
Leaves lungs, goes here, here, then here.
then the aorta.
Circulation which is a function of the right side of the heart.
In pulmonary circulation, deoxygenated blood enters the heart here, passes into here, and is pumped to the lungs via this.
right ventricle, and
via the pulmonary trunk.
In the lungs, blood unload CO
and picks up O
. The freshly oxygenated blood is carried by these to the left side of the heart.
Pulmonary or Systemic?
Left ventricle with walls 3x as thick, long pathway, encounters 5x friction.
This cavity is flattened into a crescent shape that partially encloses the left ventricle.
This is the functional blood supply of the hear, the shortest circulation of the body.
The arterial supply of the coronary circulation. They both arise from the base of the aorta and encircle the heart in the coronary sulcus.
Right and left coronary arteries
The two major branches of the left coronary artery (LCA).
left anterior descending artery
This branch of the LCA follows the anterior interventricular sulcus and supplies blood to the interventricular septum and anterior walls of both ventricles.
Left anterior descending artery
This major branch of the LCA supplies the left atrium and the posterior walls of the left ventricle.
Two major branches of the right coronary artery (RCA).
posterior interventricular artery
This major branch of the RCA runs to the myocardium of the lateral right side of the heart.
The major branch of the RCA that runs to the heart apex and supplies the posterior ventricular walls.
Posterior interventricular artery
The posterior interventricular artery merges with this artery near the apex.
Anterior interventricular artery
The 4 valves of the heart open and close in response to the differences of what on their two sides?
These valves prevent backflow into the atria when the ventricles are contracting.
The right AV valve that has three flexible cusps (flaps of endocardium reinforced by connective tissue cores).
The left AV valve with two flaps.
Bicuspid or mitral
The two semilunar valves.
This SL valve guards the base of the aorta and prevents backflow into the LV.
This SL valve guards the bases of the pulmonary artery amd prevents backflow into the RV.
Type of valve that is fashioned from three pocket-like cusps looking like a half-moon. Open and close in response to differences in pressure.
A cardiac cell's high resisteance to fatigue is due to the large size of these organelles.
This is located in the RA wall, excites about 75 times per minute. Pacemaker, sinus rhythm, determines heart rate.
Sinoatrial node (SA)
From the SA node, depolarization waves travel through gap junctions to these nodes.
Atrioventricular node (AV)
From the AV node, the impulse sweeps to this area in the superior part of the interventricular septum. Leads to left and right branches - apex.
Atrioventricular bundle, bundle of His.
Long strands of barrel-shaped cells, penetrate into the heart apex, and then turn superiorly into the ventricular walls.
Electrocardiogram: small wave, .08 s., represents the movement of the deploarization wave from the SA node through the atria.
Electrocardiogram: from ventricular depolarization until ventricular contraction, lasts .08 s.
Electrocardiogram: Ventricular repolarization, lasts .16 s. More spread out with a lower amplitude.
Time (.16 s) from the beginning of atrial excitation to the beginning of ventricular excitation.
1 contraction (systole) and 1 relaxation (distole) is known this.
When ventricles are in the last part of their diastole and have a maximum volume of blood they will contain in the cycle, this volume is called this.
End diastolic volume (EDV)
Contraction of the ventricles, closing the AV valves.
Split second phase during which ventricles are completely closed chambers and blood volume in the chambers remain constant.
Isovolumetric contraction phase
Early diastole - brief phase following the T wave - ventricles relax.
Mean pressure is 120/80
Systemic aortic or arterial
Mean pressure is 24/8
The volume of blood pumped out by one ventricle with each beat. Correlates with the force of ventricular contraction.
Stroke volume (SV)
Amount of blood pumped out by each ventricle in 1 min.
Formula for finding cardiac output.
CO = HR x SV
Imbalances in these can pose real dangers to the heart.
Plasma electrolyte, especially K.
Hormone that enhances heart rate and contractility.
Hormone that increases metabolic rate and body heat production. In large quantities, it causes slower more sustained increases in heart rate.