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A&P Ch 22
Cardiovascular System: The Heart
Question | Answer |
---|---|
To which side of the body does the apex of the heart point? | To the left |
What consists of inelastic dense irregular connective tissue? | Fibrous pericardium |
This layer of the heart wall consists of mesothelium and connective tissue. | Epicardium |
This is used to increase the capacity of the atrium | Auricle |
This marks the boundary between the ventricles. | Anterior interventricular sulcus and posterior interventricular sulcus |
As the right ventricle contracts where does blood move? | Into the pulmonary trunk |
In a fetus, this structure temporarily shunts blood from the pulmonary trunk into the aorta. | Ductus arteriosus |
Which valve prevents blood from flowing back into the right ventricle? | Pulmonary valve |
Cardiac muscle fibers electrically connect to neighboring fibers by which structures? | Gap junctions |
Atrial depolarization is marked by which wave? | P wave |
This is the mass of tissue from the sternum to the vertebral column between the lungs. | Mediastinum |
Through which structure does blood pass from the right atrium to the right ventricle? | Tricuspid valve |
From the left ventricle, where does blood pass? | Aortic semilunar valve |
This is a network of specialized cardiac muscle fibers that provide a path for each cycle of cardiac excitation to progress through the heart. | Conduction system |
Formula regarding stroke volume or SV | SV equals end diastolic volume or EDV minus end systolic volume or ESV |
This is the layer that surrounds and protects the heart. | Pericardium |
This is used to reduce the friction between membranes of the heart. | Pericardial or serous fluid |
Which layer of the heart wall consists of cardiac muscle tissue? | Myocardium |
How are cardiac muscle fibers connected? | By thickenings of the plasma membrane, called intercalated discs |
What is the function of the gap junctions within each intercalated disc? | To allow action potentials to conduct from one cardiac muscle fiber to the next |
Which vessel drains blood from the upper limbs and head into the heart? | Superior vena cava |
What heart structures carry deoxygenated blood? | Right atrium and ventricle |
As the left ventricle contracts where does blood move? | Into the aorta |
As each atrium contracts, where does blood move? | Through an atrioventricular valve |
In this disorder the aortic valve is narrowed. | Aortic stenosis |
These vessels distribute oxygenated blood to the myocardium. | Coronary arteries |
The sequence of structures that allows the normal sequence of excitation to progress through the heart. | Sinoatrial node, Atrioventricular node, Bundle of His, Purkinje fibers |
This electrical event represents repolarization of the ventricle. | T wave |
Which part of the heart can initiate a contraction? | Sinoatrial node |
This term refers to the period during a cardiac cycle when contraction occurs and blood pressure rises. | Systole |
The second heart sound represents which of the below events? | Semilunar valves closing |
This is the volume of blood ejected from the left ventricle into the aorta each minute. | Cardiac output |
Which of these periods represents greatest cardiac output? | Ventricular systole |
This part of the brain regulates heart rate. | Medulla oblongata |
Stimulation of which nerve reduces heart rate? | Vagus nerve |