Chapter 19 heart&CVS
serves to both: anchor the heart within the thoracic cavity, and prevent the heart from over filling with blood:
Function of fibrous pericardium
The muscle impulse initiated in the S.A. node, travels to the A.V. node via:
Gap junctions
Superior and inferior vena cava, and aorta
Great vessels
The cardiac center of the medulla oblongata, provide autonomic innervation of the heart, which modulates the:
Heart rate, and force of contraction
Blood that is ______ in oxygen, from the left side of the heart, is pumped into the _______.
High, aorta
Enlargement of the heart, commonly seen in young athletes is caused by this condition:
Hypertrophic cardiomyopathy
The cardiac centers are composed of a sympathetic cardioacceleratory center, which ________ heart rate, and force of contraction.
Increase
Sympathetic innervation has what effect on the heart beat?
Increases
1. S.A. node fires A.P. 2. A.P. reaches a.v. node, via gap junctions. 3. A.P. is delayed at a.v. node. 4. A.P. travels down the bundle branches. 5. A.P. travels up purkinje fibers.
Initiation and conduction of A.P. through the heart
During the this phase of the cardiac cycle, the bicuspid, pulmonary semilunar, mitral, and tricuspid valves are all closed.
Isovolumetric
Prevents back flow of blood into left atrium
Left atrioventricular
Responsible for pumping oxygenated blood to the body.
Left ventricle
The primitive ventricle, forms most of the:
Left ventricle
P-waves, Q.R.S complex, and t-waves are the:
Major wave forms on an EKG.
The heart is located posterior to the sternum, left of the body's midline, between the lungs, within the:
Mediastinum
The cardiac center is within the:
Medulla oblongata
Inferior to epicardium, middle layer of the heart wall, composed of cardiac muscle tissue. Thickest of the three heart wall layers:
Myocardium
Middle layer of the heart wall and is composed of cardiac muscle tissue
Myocardium
What wave reflects the electrical changes of artrial depolarization?:
P wave
Cells of the S.A. node are the:
Pacemaker of the heart
Ability to reach threshold without stimulation.
Pacemaker potential
Cone ch sped muscular projections of the right ventricle wall are called:
Papillary muscles
What innervation decreases the heart rate?:
Parasympathetic
Composed of simple squamous epithelium, and an underlying delicate layer composed of areolar connective tissue. Adheres to the inner surface of the fibrous pericardium:
Parietal layer of the serous pericardium
The right, and left atrium have what muscles in common?:
Pectinate muscles
Cavity that contains serous fluid, lies inferior to the parietal layer, and superior to the visceral layer of pericardiums:
Pericardial cavity
Inflammation of the pericardium
Pericarditis
Restricts heart movement, so that it doesn't bounce around the thoracic cavity, and prevents the heart from over filling with blood.
Pericardium
Circulation that moves deoxygenated blood
Pulmonary
Cardiovascular system consists of 2 circulations:
Pulmonary and systemic
Prevents back flow of blood into right ventricle
Pulmonary semilunar
Semilunar valve between the right ventricle, and the pulmonary trunk.
Pulmonary semilunar valve
Drain blood into left atrium
Pulmonary veins
Arterial systole, results in arterial contraction. Which causes:
Pushes blood into ventricles; compresses the openings of the great veins.
During what period can cardiac muscles not be restimulated?:
Refractory
The _______ atrium, has openings from: inferior and superior vena cava, and coronary sinus.
Right
Prevents back flow of blood, into the right atrium
Right atrioventricular
Cardiac muscle stimulation: requires that the action potential initiated by the ______ _______, be spread throughout the conduction system.
S.A. NODE
Internal wall surface of each ventricle displays characteristic: large, smooth, and irregular muscular ridges, called:
Trabeculae carneae
Right a.v. valve is also called the
Tricuspid
The main parasympathetic nerves that regulate heart rate:
Vagus nerves
Inferior chambers for pumping blood away from the heart
Ventricles
Composed of simple squamous epithelium, and underlying delicate layer of areolar connective tissue. This serosal layer adheres directly to the heart.
Visceral layer of the serous pericardium
The innervation by autonomic centers in the brainstem, doesn't initiate a heartbeat; but it can increase, or decrease the rate of the beat. Is this true?
Yes
The greater the ______________, the more difficult it is to eject blood from the heart, and the lower the stroke volume will be.
Afterload
The resistance in the arteries to blood ejection from the ventricles.
Afterload
The largest systemic artery in the body:
Aorta
Prevents back flow of blood into left ventricle
Aortic semilunar
Semilunar valve between the left ventricle and aorta
Aortic semilunar valve
Ventricles pump blood into:
Arterial trunk
Blood flow into the atria from the veins is restricted; ventricles have reached their EDV; S.A. node initiates arterial contraction, are all events that takes place during what phase of the cardiac cycle?:
Atrial contraction and ventricular filling phase
Oxygenated blood flows from the left atrium, through the left _________ __________, when the valve is open, into the left ventricle.
Atrioventricular opening
Superior chambers for receiving blood
Atriums
The anterior part of Rachel atrium has has a wrinkled, flap like extension, that resemble ears, called:
Auricles
What nervous system influences the heart rate?:
Autonomic
Right side of heart, to the lungs; to the left side of the heart, to systemic cells of the body; back to the right side. Is what basic pattern?:
Basic pattern of blood flow
Left a.v. valve is also called the
Bicuspid or mitral valve
During the final stage of the cardiac cycle: as the atria relax, and blood returns to fill the ventricle, what 2 valves open?
Bicuspid, and tricuspid
Attached to the inferior diaphram, composed of tough, sense irregular connective tissue that encloses the heart, but does not attach directly to it.
Fibrous pericardium
N.a. + leak channels, fast voltage gated c.a. 2 + channels, slow voltage gated n.a. + channels, and n.a. + /k + a.t.pase are all associated with:
Cardiac node cells
The amount of blood pumped by one ventricle:
Cardiac output
An individual with a weak heart may have limitations exerting themselves, because they have little:
Cardiac reserve
Inotropic agents increase stroke volume by increasing :
Contractility, and C.a. 2 + levels
Delivers oxygen rich blood to the thick heart wall.
Coronary arteries
Supplies oxygenated blood to the muscles and other tissues of the heart, and drains deoxygenated blood from these tissues. Flows easily when heart is relaxed, inhibited when heart contracts.
Coronary circulation
Carries deoxygenated blood away from the heart wall.
Coronary veins
Parasympathetic cardioinhibitory center _______ heart rate.
Decreases
The amount of blood left in the ventricles, at the end of the ventricular contraction.
End systolic volume
Composed of a simple squamous epithelium, called endothelium, and a layer of areolar connective tissue.
Endocardium
Internal surface of the heart, and covers the external surfaces of the heart valves is
Endocardium
The internal surface of the heart, and the external surfaces of the heart valves are covered by:
Endocardium
The outermost heart layer, also called the visceral layer of serous pericardium
Epicardium
Factors that increase venous return:
Exercise, and decrease heart rate
Other set of valves that mark the boundary between a ventricle and it's associated arterial trunk:
Semilunar valves
What determines cardiac output?
Stoke volume, and heart rate
Drains blood into the right atrium
Superior and inferior vena cava
The large veins deliver blood to the heart into an atrium:
Superior and inferior vena cava
Blood vessels visible in the posterior view of the heart :
Superior and inferior vena cavae, and pulmonary veins
Circulation that moves oxygenated blood
Systemic
In comparison: the left ventricle requires thicker walls, than the right, to generate enough pressure to force the blood into the aorta, and then through the entire:
Systemic circulation