- blood flow into the cornoary arteries is greatest when?
- during ventricular diastole
- during the cardiac cycle, what contracts first? second?
- both atria contract and then both ventricles contract.
- four pulmonary veins return blood from the lungs to where?
- the left atrium of the heart.
- if blood returns from the body to the right atrium, where must it first travel to before being pumped back out to the body?
- the lungs
- what are auricles?
- expanpable pouches on the right and left atria.
- what are small vessels that control the amount of blood flowing into the capillary bed called?
- arterioles
- what are the largest arteries in the body capable of withstanding large pressure changes?
- elastic arteries
- what are the smallest blood vessels?
- capillaries
- what are the terminal branches of the conducting systems called?
- purkinje fibers
- what arteries have a high percentage of smooth muscle?
- muscular arteries
- What delays the signal?
- the atrioventricular (AV) node
- What determines the heart rate?
- sinoatrial (SA) node
- what do AV valves do?
- prevent retrograde blood flow from ventricles to atria when ventricles contract.
- what do semilunar valves do?
- Prevent blood from re-entering ventricles from great vessels during ventricular diastole
- what does elastic rebound/recoil do?
- propels blood forward.
- what does the cardiovascular system mainly transport?
- gases, nutrients, and metabolic waste products.
- what happens in mitral valve prolapse (clinical correlate)
- the valve flips up or doesn't close correctly.
- what happens in mitral valve stenosis?
- the valves narrow and doesnt' completely open or close.
- what is an apical beat?
- maximal pulsation of the heart that can sometimes be felt and seen in the fifth intercostal space on the left side of the body.
- what is teh pericardial cavity?
- the space between the parietal and visceral layers of serous pericardium; contains a think film of pericardial fluid.
- What is the Consequence of low resistance for blood returning to the heart?
- decline in BP in veins
- what is the function of valves?
- they prevent backflow of blood (regurgitation)
- what is the groove between the R and L ventricles on the inferior surface of the heart containing the posterior interventricular artery and the middle caridac vein?
- posterior interventricular groove (sulcus)
- what is the groove between the right and left ventricles on the anterior surface of the heart called? (contains the anterior interventricular artery and the great cardiac vein)
- the anterior interventriclar groove (sulcus)
- what is the groove located between the atria and the ventricles called?
- antrioventicular groove (aka coronary sulcus)
- what is the heart wall layer that overlies the cardiac vessels.
- the epicardium
- what is the hollow central canal of a blood vessel called?
- the lumen
- what is the inner layer of the heart wall? what does it line?
- endocardium. lines the chambers of the heart and is continuous with the lining of the blood vessels that enter/exit the heart.
- what is the middle layer of the heart wall? what is it composed of? where is it thickest and thinnest?
- Myocardium. composed of cardiac muscle. thickest in ventricles and thinnest in atria.
- what is the outermost layer of the heart?
- fibrous pericardium
- what is the route by which an electrical impulse can travel fro the atria to the ventricles?
- the AV bundle
- what kind of neurons does the cardiac plexus contain?
- both ANS sympathetic and parasympathetic.
- what structure stops the direst transmission of an electrical signal between the atrial and ventricular musculature.
- the fibrous skeleton
- where do cardiac veins return blood to?
- the right atrium
- where does the left pump sends blood through?
- systemic circuit (body)
- where does the pulmonary trunk exit the heart?
- the right ventricle on its anterior surface.
- where does the right pump send blood through?
- pulmonary circuit (lungs)
- why do capillaries lack tunica externa or media?
- To permit exchange between blood and surrounding interstitial fluids by diffusion through wall or gas in the wall (two way exchange)
