Anatomy Ch 21
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Anatomy Ch 21
Anatomy Cardiovacular system heart
The Cardiovacular system: The heart
All of the tissue and fluid in the body rely on the cardiovascular system to maintain what?
The proper functioning of the cardiovascular system depends on the activity of the...
heart, which can vary its pumping capacity depending on the needs of the peripheral tissues.
Cardiovascular system can be subdivided into two closed circuits which are?
Pulmonary Circuit and Systemic Circuit.
What is the Pulmonary circuit?
It carries oxygen-poor blood from the heart to the lungs and back
What is the Systemic Circuit?
It transports oxygen-rich blood from the heart to the rest of the body and back.
What is an Artery?
Arteries car blood away from the heart.
What are Veins?
Veins return blood to the heart.
What are Capillaries?
They are tine vessels between the smallest arteries and veins.
How man chambers does the hear contain?
What does the Right Atrium and Ventricle do?
They pump blood into the pulmonary arteries.
What does the left Atrium do?
It receives blood from the pulmonary veins.
What does the Atria do?
It collects blood returning to the heart.
What do ventricles do?
They discharge blood into vessels to leave the heart.
What is the heart surround by?
The Pericardial Cavity
The Pericardial Cavity is lined by what?
The small amount of lubricating fluid on pericardium is called?
What covers the heart's outer surface?
Visceral Pericardium (Epicardium )
____________ lines in the inner surface of the ___________ that surrounds the heart and helps prevent overfilling.
Parietal Pericardium; pericadial sac
The heart lies in the anterior portion of the?
What are the three layers of the heart wall?
Epicardium(the visceral pericardium)
Myocardium(the muscular wall of the heart)
Endocardium(the epithelium covering)
The bulk of the heart consist of muscular what?
What are cardiac muscles cells?
What are Coronary arteries?
They supply blood to the heart.
Cardiac muscle cells do not require ________ to contract.
Cardiocytes are interconnected by?
What do Intercalated discs do?
They join cardiac muscle cells through, desmosomes, myofibrils, and gap junction.
Since cardiac muscle cells are connected by intercalated discs, how do they function?
They functions like a single, enormous cell.
What is fibrous skeleton?
it is the internal connective tissue of the heart.
What are the functions of fibrous skeleton of the heart?
To stabilize the heart's contractile cells and valves
To support the muscle cells, blood vessels, and nerves
To distribute the forces of contraction
To add strength and elasticity
To physically isolate the atria from the ventricles
What is Auricle(Atrial Appendage)?
Is an expandable extension of the atrium.
What is the Coronary Sulcus?
It is the deep groove between the atria and the ventricles.
What are two other shallower depression than that coronary sulcus?
Anterior interventricular sulcus and Posterior interventricular sulcus.
The great vessels are connected to the superior end of the heart at the?
The inferior, pointed tip of the heart is the?
The heart sits at an angle to the longitudinal axis of the body and presents the following"
Superior, inferior, left and right borders
What are the surfaces of the heart?
Sternocostal surface and diaphragmatic surface
How is sternocostal surface formed?
It is formed by the anterior surfaces of the right atrium and ventricle
How is the diaphragmatic surface formed?
It is formed primarily by the posterior, inferior wall of the left ventricle.
What separates the atria?
The ventricles are divided by what?
The openings between the artria and ventricles contain what?
They contain folds of connective tissue covered by endocardium.
Where does the right atrium receive blood from?
The systemic circuit.
The right atrium receives blood from the systemic circuit through two great veins which are?
The superior and inferior vena cava.
The atrial walls contain prominent muscular ridges called?
What does the coronary veins do?
They return blood to the coronary sinus which opens into the right atrium.
During embryonic development an opening called the ________ penetrates the interatrial septum.
This opening closes after birth, leaving a depression termed called?
Blood flow from the right atrium into the right ventricle through the what?
Right Atrioventricular (AV) or tricuspid valve
The Tricuspid Valve consist of three _______ of fibrous tissue braced by the ____________ that are connected to _____________.
Cusps; Chordae Tendineae; Papillary Muscles
Blood leaving the right ventricle enters the __________ after passing through the _________.
Pulmonary trunk; pulmonary valve.
The pulmonary trunk divides to form what?
The left and right pulmonary arteries
The left atrium receives oxygenated blood from what?
The left and right pulmonary veins.
Blood leaving the left atrium flows into the left ventricle through what?
Left atrioventricular (AV) valve or bicuspid valve
Why is the left ventricle the largest and thickest of the four valves?
Because it must pump blood to the entire body.
Blood leaving the left ventricle passes through the ________ and into the systemic circuit via the _________.
Aortic valve and ascending aorta.
Blood passed the ascending aorta through the ________ and into the _________
Aortic arch; descending aorta.
What are the four components to the AV valves?
1. Ring of connective tissue attached to the fibrous skeleton of the heart
3. chordae tendineae
4. papillary muscles.
What are the two Semilunar valves?
Aortic valve and pulmonary valve.
Valves normally permit blood flow in only one direction, preventing ________ of blood.
The closure of valves and rushing of blood through the heart cause characteristic ________ that can be heard during auscultation.
What does Coronary circulation supply?
It supplies blood to the muscles of the heart to meet the high oxygen and nutrient demands of the cardiac muscle cells.
Where do Coronary Arteries originate?
It originate at the base of the ascending aorta, and each gives rise to two branches.
There are two branches that the right Coronary artery gives rise to, what branches are they?
Right Marginal Branch and posterior interventricular branch
What does the left coronary artery give rise to?
They circumflex branch and anterior interventricular branch.
Interconnections between arteries called _____ ensure a constant blood supply.
The ______ and _______ carry blood from the coronary capillaries to the ________.
Great and middles cardiac veins; coronary sinus.
What does the Anterior cardiac vein do?
They drain the anterior surface of the right ventricle and empty directly into the right atrium.
The cardiac cycle consists of periods of?
Atrial and ventricular systole
Atrial and ventricular diastole.
What is Automaticity and Autorthythmicity?
When cardiac muscle tissue contracts on its own, without neural or hormonal stimulation
What do Nodal Cells establish?
The rate of cardiac contraction
What do conducting fibers distribute?
The contractile stimulus to the general myocardium.
What do Nodal Cells do?
They depolarize spontaneously and determine the heart rate.
What is found in the sinoatrial (SA) node normally establishes the rate of contraction?
From the SA node, the stimulus travels over the ________ to the _________, then to the ________, which divides into a _____ and _________.
Internodal pathways; atrioventricular (AV) node; AV bundle; Right and left bundle branch.
What are Purkinje Cells?
They convey the impulses to the ventricular myocardium .
During diastole what happens to the chambers of the heart?
They fill up.
During on cardiac cycle the heart spends most of its time in what?
During the period of systole the inner volume of atrial chamber _________.
What produces an increase in heart rate and force of contraction, while acetylcholine produces a decrease in heart rate and contraction?
What can modify the basic heart rate that is established by the pacemaker cells?
ECG analysis reveals what?
The conduction of the conducting system
The __________ in the medulla oblongata activated sympathetic neurons; the _________ governs the activities of the parasympathetic neurons.
Cardioacceleratory center; cardiohibitory center