Vascular System Flashcards
Aorta
Blood is pumped into
branches into a series of arteries
Route of blood
Deoxygenated blood is pumped into the AORTA-> branches into arteries which then branch into arterioes which then branch into capillaries–> blood is oxygenated –> capillaries converge into venules –> converge into veins –> blood deoxygenated–> blood back to the heart
Right side of heart
pumps deoxygenated blood into pulmonary circulation
Right ventricle not as muscular
ventricle
lower chambers of heart, right and left
Left side of heart
pumps oxygenated blood into systemic circulation (throughout the body)
Left ventricle more muscular than right because it has to pump blood to all the body, has to pump against a higher resistance
atrioventricular valves
located between the atria and ventricles on both sides of the heart prevent backflow of blood into the atria
tricuspid valve
valve on right side of the heart
has three cusps
mitral valve
valve on left side of the heart
has two cusps
semilunar valve
have three cusps
located between the left ventricle and the aorta (aortic valve) and between the right ventricle and the pulmonary artery (pulmonic valve)
systole
period of heartbeat during which the ventricles contract
diastole
period of heartbeat when cardiac muscles relax and blood drains into all four chambers of the heart
cardiac output
total volume of blood the left ventricle pumps out per minute. heart rate x stroke volume
Sinoatrial Node
(SA NODE) pacemaker, small mass of specialized tissue located in the wall of the right atrium, spreads impulses through both atria stimulating them to contract simultaneously. Ordinary cardiac contraction originates in and is regulated by the SA node
Atrioventricular Node
AV node, impulse from SA node arrives here, conducts slowly, allows time for atrial contraction and for the ventricles to fill with blood
Bundle of His (AV bundle)
carries impulse from SA–>AV–> bundle of His, which branches into the right and left bundle branches
purkinje fibers
impulse goes through here after SA->AV–> AV bundle, in the walls of both ventricles which causes a strong contraction
Autonomic Nervous System
modifies the rate of heart contraction
vagus nerve
Parasympathetic system innervates the heart by using this, causes a decrease in heart rate.
Sympathetic System Action
innervates the heart via the cervical and upper thoraic ganglia and causes an increase in heart rate. Adrenal medulla exerts hormonal control via epinephrine secretion which causes an increase in heart rate
Three types of blood vessels
arteries, veins, and capillaries
Arteries
thick walled, muscular, elastic vessels, transport oxygenated blood away from the heart except for the pulmonary arteries which transport deoxygenated blood from the heart to the lungs.
veins
relatively thin arteries, inelastic vessels that conduct deoxygenated blood to the heart (EXCEPT FOR PULMONARY VEINS)
pulmonary veins
carry oxygenated blood from the lungs to the heart
stroke volume
volume of blood pumped out of the left ventricle per contraction