Chapter 18 Flashcards
The blood vessels that carry blood to and from the lungs form the ___ ___
Pulmonary circuit
The ____ is the transport system pump, and the hollow blood vessels are the delivery routes. (Two pumps side by side)
Heart
The blood vessels that carry blood to and from all body tissues form the ___ ___
Systemic circuit
The heart is enclosed in a double-walled sac called the ___
Pericardium
At the superior margin of the heart, the parietal layer attached to the large arteries exiting the heart, and then turns inferiorly and continues over the external heart surface as the __ ___ also called ___ an integral part of the heart wall.
Visceral layer, also called epicardium
Between the parietal and visceral layers is the slitlike ___ ___ which contains a film of serous fluid.
Pericardial cavity
The superficial ____ is the visceral layer of the serous pericardium.
Epicardium
The middle layer the ____ is composed mainly of cardiac muscle and forms the bulk of the heart.
Myocardium
The third layer of the heart wall the ____ is a glistening white sheet of endothelium resting on a thin connective tissue layer.
Endocardium
The ___ ___ ___ returns blood from body regions superior to the diaphragm.
Superior vena cava
The ___ ___ ___ returns blood from body areas below the diaphragm
Inferior vena cava
The ___ ___ collects blood draining from the myocardium.
Coronary sinus
Four ___ ___ enter the left atrium which makes up most of the hearts base. (Transport blood from the lungs back to the heart)
Pulmonary veins
The right ventricle pumps blood into the ___ ____ which routed the blood to the lungs where gas exchange occurs.
Pulmonary trunk
The left ventricle ejects blood into the ___ the largest artery in the body.
Aorta
The two ___ ___, one located at each atrial ventricular junction prevent back flow into the atria when the ventricles contract.
Atrioventricular valves
The right AV valve the ___ ___ has three flexible cusps (flaps of endocardium reinforced by connective tissue cores)
Tricuspid valve
The left AV valve with two cusps is called the ___ ___ because it resembles the two sides bishops miter or hat.
Mitral valve (bicuspid valve)
Attached to each AV valve flap are tiny white collagen cords called __ ___ (tendinous cords) “heart strings” which anchor the cusps to the papillary muscles protruding from the ventricular walls.
Chordae tendineae
The __ and ___ (___) ___ guard the bases of the large arteries issuing from the ventricles and prevent back flow into the associated ventricles.
Aortic and pulmonary (semilunar) valves
The __ ___ the functional blood supply of the heart is the shortest circulation in the body.
Coronary circulation
The crescent shaped __ ___ is located in the right atrial wall just inferior to the entrance of the superior vena cava. ( the heart’s pacemaker) generates impulses about 75 times/min
Sinoatrial (SA) node
___ __ determines the heart rate
Sinus rhythm
___ ___ is striated and contracts by the sliding filament mechanism.
Cardiac muscle
The heart has 4 chambers two superior ___ and two inferior ___.
Atria
Ventricles
Small, wrinkled, protruding appendages called ____ which increase the atrial volume somewhat the right and left atria are remarkably free of distinguishing surface features.
Auricles
Bundled of muscle tissue that form ridges in the walls are ____ because they look like the teeth of a comb.
Pectinate muscles
The interatrial septum beard a shallow depression the ___ ___ that marks the spot where an opening the foramen ovale existed in the fetal heart.
Fossa ovalis
____ ___ ___ ____ consists of noncontractile cardiac cells specialized to initiate and distribute impulses throughout the heart so that it depolarizes and contracts in an orderly sequential manner
Intrinsic cardiac conduction system
From the SA node the depolarization wave spreads via gap junctions throughout the atria and via the internodal pathway to the __ ___ located in the inferior portion of the interatrial septum immediately above the tricuspid valve. (Delays the impulse approximately 0.1 seconds)
Atrioventricular (av) node
Impulse passes from atria to ventricles via the
Atrioventricular bundle (bundle of his)
Heart is stimulated by the sympathetic ___ ____.
Cardioacceleratory center
Heart is inhibited by the parasympathetic ___ ___.
Cardioinhibitory center
___ ___ are associated with closing of heart valves.
Heart sounds (lub dup)
An ____ is a graphic record of heart activity
Electrocardiogram (ECG)
The small _ __ lasts about 0.08 s and results from movement of the depolarization wave from the SA node through the atria.
P wave
The large ___ ___ results from ventricular depolarization and precedes ventricular contraction.
QRS complex
The __ __ caused by ventricular repolarization typically last about 16 s.
T wave
The ___ ___ includes all events associated with blood flow through the heart during one complete heartbeat
Cardiac cycle
Contraction of heart muscle is ___
Systole
Relaxation of heart muscle is ____
Diastole
The ___ ___ is the time (about 0.16 s) from the beginning of atrial excitation to the beginning of ventricular excitation
P-R interval
If the Q wave is visible it marks the beginning of ventricular excitation and for this reason this interval is sometimes called ___ ___
P-Q interval
During the ___ ___ of the ECG when the action potential of the ventricular myocytes are in their plateau phased the entire ventricular myocardium is depolarized.
S-T segment
The ___ ____ lasting about 0.38 s is the period from the beginning of ventricular depolarization through ventricular repolarization
Q-T interval
___ ___ pressure in the heart is low blood returning from the circulation is flowing passively through the atria and the open AV valves into the ventricles and the aortic and pulmonary valves are closed.
Ventricular filling (mid to late diastole)
___ ____ as the atria relax the ventricles begin contracting.
Ventricular systole (atria in diastole)
___ ____ during this brief phase following the T wave the ventricles relax.
Isovolumetric relaxation
__ ___ is the amount of blood pumped out by each ventricle in 1 minute.
Cardiac output
