Blood Vessels and Circulation EQ: How does blood flow throughout our bodies?

Root Words Brady Slow Bradycardia Diastol Dilation Diastolic pressure -gram Something written Electrocardiogram Tachy Rapid Tachycardia Systol Contraction Systolic pressure

Veins and Arteries have 3 wall layers Intima- Inner layers Media- Middle Layer Adventitia- Outer layer

Veins and Arteries Arteries: Carry blood away from the heart Veins: Return blood to the heart

Other vessels Arterioles: Are the smallest branches of arteries Capillaries: Smallest blood vessels, serve to distribute oxygenated blood from arteries to tissue around the body Venules: Small blood vessels that merge with veins and return blood from tissue to the heart

Capillary Beds Collection of capillaries where oxygen is exchanged through diffusion.

Venous Valves Folds within veins which prevent blood from flowing backwards Compression pushes blood toward heart Video

Factors affecting blood flow Blood Pressure (BP) Arterial pressure to overcome resistance

Factors affecting blood flow Blood Pressure (BP) Arterial pressure to overcome resistance Venous Pressure Pressure in the venous valves

Factors affecting blood flow Blood Pressure (BP) Arterial pressure to overcome resistance Venous Pressure Pressure in the venous valvues Vascular Resistance Due to friction between blood and vessel walls Depends on vessel length and vessel diameter

Pressures Systolic Pressure The blood pressure when the heart is contracting When measuring blood pressure, it is the first number (120/80) mm Hg (Millimeters of mercury)

Pressures Diastolic Pressure The second number (120/80) The time when the heart is relaxing and dilating. The second number (120/80)

Adjusting flow of blood Vasodilators Accelerate blood flow at the tissue level by widening blood vessels Vasoconstrictors Decrease blood flow to tissue by narrowing blood vessels Often used on heart attack patients

ECG AKA Electrocardiography

ECG Waves Ions are released to polarize and depolarize, causing muscle contraction

ECG Waves P Wave- Artia are contracting, pumping blood into ventricles

ECG Waves P Wave- QRS Complex Artia are contracting, pumping blood into ventricles QRS Complex Represents ventricular depolarization and contraction

ECG Waves P Wave- QRS Complex Artia are contracting, pumping blood into ventricles QRS Complex Represents ventricular depolarization and contraction

ECG Waves P Wave- QRS Complex T Wave Artia are contracting, pumping blood into ventricles QRS Complex Represents ventricular depolarization and contraction T Wave Represents ventricular repolarization

LEFT SIDE ACTIVITY Draw a vein and label the three wall layers. Draw a ECG wave and explain what is occurring.