heart lab part 2

Pulmonary circuit

Right ventricle pumps blood into pulmonary trunk divides into right and left pulmonary arteries that enter lungs inside the lungs capillaries exchange gases, then oxygenated blood flows back through the pulmonary veins to the left atrium

Systemic circuit

Blood returns from lungs to left atrium, which pumps the left ventricle, blood in left ventricle leaves via the aorta, systemic arteries branch off from aorta into systemic capillaries in peripheral tissues where cell wastes and CO2 enter blood. Capillaries merge from systemic veins to vena cava which pours deoxygenated blood into right atrium

Blood flows from:

deoxygenated Right atrium→ tricuspid valve→right ventricle→ pulmonary valve→pulmonary arteries and lungs→oxygenated pulmonary veins and left atrium→biscupid valve→left ventricle →aortic valve→ to the entire body

Systemic circuit blood flows from:

Left ventricle→ arteries to body→ veins back to the heart → right atrium → right ventricle→ lungs→ left atrium → left ventricle

Coronary circulation

Cardiac muscle is never at rest needs oxygen for contraction

Coronary arteries

Branches off aorta and penetrates myocardium

Right coronary arteries

Passes along the coronary sulcus to supply the right atrium beaches in marginal arteries and the posterior inter ventricular artery

Left coronary arteries

Supplies blood to left atrium, left ventricle and interventricular septum

Circumflex artery

Goes around heart and supplies left ventricle and anterior interventricular artery

Left coronary arteries and right coronary arteries

Unite in posterior coronary sulcus

Cardiac veins

Collect deoxygenated blood from myocardium

Great cardiac veins

Follows anterior interventricular sulcus and curves around heart to drain myocardium

Posterior cardiac vein

Drains myocardium of the left coronary artery

Small cardiac vein

Drains superior right of heart

Middle cardiac vein

Drains myocardium of right coronary atrium

Coronary sinus

Where cardiac veins merge in coronary sulcus

Autorhythmicity

Cardiac muscle producing it’s own contraction and relaxation with stimulation from nerves

Conducting system function

Produces and coordinates electrical current for myocardium contraction consists of nodal cells that produce and send electrical currents

SA node

Pacemaker located at superior vena cava, RA strimulates AV node

AV node

Lower floor of right atrium

Atrioventricular bundle

Directs impulse from AV node toward the ventricles passing into interventricular septum

Bundle branches

Bundle of his branches into right and left branches within the septum

Purkinje fibers

Bundle branches distributes electrical impulses directly to cardiocytes