Artery: Structure

o Layer of collagen and elastic fibers in outer wall very thick to prevent bulges/leaks

o Thick wall of artery withstands high pressureo Lumen or space within artery is relatively narrow, maintaining

HBPo Thick layer of elastic, muscular tissues to pump blood

Bradycardia: Heart rate < 60 bpm

Capillaries: Structure

o Lumen is narrow so can fit into small placeso Pores found between endothelial cells lining capillary, allowing

plasma to leak into adjacent tissues and for phagocytes to squeeze out to search for pathogens

o Thin cell lining for easier diffusion

Cardiac Output: Heart Rate x Stroke Volume. Increases when HR, contractility, end diastolic volume are increased.

Components of Blood: erythrocytes (RBC), leucocytes (WBC), platelets, plasma. Blood carries oxygen, nutrients, CO2, hormones, antibodies, urea.

Coronary Arteries: Blood vessels that supply heart muscle with oxygen and nutrients.

Coronary Sinus: Collection of veins that form large vessel collecting blood from heart. Delivers deoxygenated blood to right atrium.

Heart Sounds

S1 is caused by closure of AV valves/tricuspid/mitral (beginning of systole)

S2 closure of SL valves (semilunar valves), diastole

Mitral Valve: Left AV valve. Closed during ventricular systole

Pulmonary Circuit: Heart’s right half pumps de-oxygenated blood to lungs.

Semilunar Valves: When they are closed, blood is entering the ventricles.

Sinoatrial Node: Composed of cardiac tissue, pacemaker of the heart.

Systemic Circuit: Heart’s left half pumps oxygen-rich blood to all body regions.

Tachycardia: Heart rate > 100 bpm

Tricuspid Valve: Right AV valve. Between right atrium and right ventricle

Vein: Structure

o Thin wall, can be compressed by adjacent muscles, to press venous blood forward

o Lumen is large so slow moving blood may flow througho Layers of collagen in outer wall thin, as little danger of bursting due to low

pressure