What is systolic

1. Atrial contract
2. AV valves open
3. Semilunar valves closed

1. atria Relax
2. Vetnricles Contract
3. AV Valves forced closed
4. Semiunar Valves still closed -
5. Pressure builds

1. Atrai relax
2. Vetnricles contract
3. AV valves remain closed
4. Semilunar valves open b/c of pressure

1. Atrai and ventricles relax
2. AV valves closed
3. Semilunar Valves closed
4. Atria passively filling with blood

1. Atria and Ventricles relax
2. Atria passively fill with blood
3. AV valves open
4. Semilunar valves closed

What are the three classes of vessels

1. arteries - blood away from the heart
2. Caprillaries - gas and nutrient exchange b/t vessels and tissues
3. Veins - transport blood back to heart

Structure of Vessel walls

(3)

1. Tunica intima - innermost layer - simple squamous endothelium
2. Tunica Media (largest in arteries)  - circularly arranged smooth muscle fibers - VC and VD
3. Tunica Externa - Largest in veins  - collagen and elastic fibers that run longitudinally

1. Elastic
2. Muscular
3. Arteriols

Elastic Arteries

1. Largest arteries
2. Conducting arteries beween heart and muscular arteries
3. High elastin allows arteries to stretch - dampen surges and reduce bp from contractions
4. Found in Aorta and many branches

1. Distributing arteries - body organs and tissues
2. this tunica media
3. actively changes diameter of lumen to regulate amount of b/f to the tissues
4. Brachial, coronary, inferior mesenteric

Arterioles

1. Smallest arteries
2. Lead to the capillary beds
3. Diameter regulated by local tissue factors and sympathetic nervous system

1. Functional units of the cardiovascular system
2. Smallest vessels
3. Capillary bed - network of capillaries that run throughout the body
4. 3 types

What are the three types of Capillaries

1. Continuous - Most common - muscles, lungs, skin
2. Fenestrated - small pores - Small intestine and kidney
3. Sinusoid - Big holes - bone marrow, liver, spleen unbilical cord

Name two veins that carry oxygenated blood

Pulmonary vein

Unbilical cord

1. Smallest veins
2. Primary location of diapedesis - WBC leaving blood - b/c of low pressure
3. Venules join to form veins

Diverts blood from the liver to vena cava