Question | Answer |
The heart is located in the | thoracic cavity between the lungs |
The thoracic cavity between the lungs is called the | mediastinum |
The heart is enclosed in the | pericardial membranes |
The outermost layer of the pericardial membranes is the | fibrous pericardium |
Lining the fibrous pericardium is the | parietal pericardium |
On the surface of the heart muscle is the | visceral pericardium |
The visceral pericardium is often called the | epicardium |
Between the parietal and visceral pericardial membranes is | serous fluid |
Myocardium | Cardiac muscle |
The chambers of the heart are lined with | endocardium |
The important physical characteristic of the endocardium is not its thinnes, but rather its | smoothness |
The upper chambers of the heart are the | right and left atria |
Interatrial septum | the common wall of the myocardium |
The lower chambers of the heart are the | right and left ventricles |
The right and left atria have _______ walls | thin |
The right and left ventricles have ______ walls | thick |
The ventricles are separated by teh | interventricular septum |
The atria receive blood from the | body or lungs |
The ventricles pump blood to either the | lungs or body |
Caval veins | return blood from the body to the right atrium |
The superior vena cava carried blood from the | upper body |
The inferior vena cava carries blood from the | lower body |
From the right atrium, blood will flow through the _______ _____________ _____ into the right ventricle | right atrioventricular (AV) valve |
The left atrium receives blood from the lungs by the way of four | pulmonary veins |
Blood flows into the left ventricle through the | left atrioventricular (AV) valve |
The left atrioventricular (AV) valve is also called the | mitral valve or bicuspid valve |
Another function of the atria is the production of a hormone involved in | blood pressure maintenance |
When the walls of the atria are stretched by increased blood volume or blood pressure, the cells produce | atrial natriuretic peptide (ANP) |
Atrial natriuetic peptide is also called | atrial natriuertic hormone (ANH) |
ANP decreases | the reabsorption of sodium ions by the kidneys |
At the junction of a large pulmonary artery and the right ventricle is the | pulmonary semilunar valve |
Papillary muscles | columns of myocardium projecting into the lower part of the right ventricle |
Chordae tendineae | Strands of fibrous connective tissue that extend from the papillary muscles to the flaps o the tricuspid valve |
The left ventricle pumps blood to the body through the | aorta |
The aorta is the ________ artery of the body | largest |
At the junction of the aorta and the left ventricle | aortic semilunar valve |
The right side of the heart receives _________ blood from the body | deoxygenated |
The left side of the heart receives _________ blood from the lungs | oxygenated |
Ischemic | deprived of its blood supply |
Infarct | an area of necrotic (dead) tissue |
Myocardial inarction is commonly called a | heart attack |
Systole | contraction |
Diastole | relaxation |
Heart murmur | An extra sound during a heart beat, caused by the valves not closing properly |
The natural pacemaker of the heart is the | SA node |
From the SA node, impulses for contraction travel to the | atrioventricular (AV) node |
Atrioventricular bundle | The pathway for the electrical impulses to travels from the atria to the ventricles |
The atroventricular bundle is also called the | bundle of His |
Bundle branches | branches that come off of the atrioventricular bundle |
From the bundle branches, electrical impulses travel along | Purkinje fibers |
Arrhythmias are | irregular heartbeats |
ventricular fibrillation | a very rapid and uncoordinated ventricular beat that is totally ineffective for pumping blood |
A normal resting heart rate for an adult is | 60 to 80 beats per minute |
Bradycardia | A resting heart rate of less than 60 bpm (except for athletes) |
Tachycardia | a prolonged or consistent rate greater than 100 bpm |
A child's normal heart rate may be as high as | 100 bpm |
An infant's normal heart rate may be as high as | 120 bpm |
A near-term fetus' normal heart rate may be as high as | 140 bpm |
Stroke volume | The amount of blood pumped by a ventricle per beat |
Cardiac output= | stroke volume x pulse (heart rate) |
Starling's Law of the heart states | that the more the cardiac muscle biers are stretched, the more forcefully they contract. |
The _______ of the brain contains the cardiac center | medulla |
The two cardiac centers of the brain are the | accelerator center and the inhibitory center |
Pressoreceptors in the carotid sinuses and aortic sinus detect | changes in blood pressure. |
Chemoreceptors in the carotid bodies and aortic body detect | changes in oxygen content of the blood |