33.1 Overview  Blood circulates through our entire body - Internal transportation  Blood is pumped by heart and carries….  Oxygen  Nutrients  Hormones  Waste Products To the cells in our body…… Components of Circulatory System Blood Heart Blood Vessels What are the 3 main types of blood vessels?

Human HEART Your heart is composed almost entirely of ______. Powerful contractions of the myocardium (heart muscle) pump blood through the circulatory system.

Structure of the HEART 2 Sided Pump Right: body  heart  lungs Left: lungs  heart  to body Upper Chambers Atria (R/L Atrium) Receive blood Lower Chambers Ventricles (R/L Ventricle) Pump blood out of heart

The Chambers & The Valves or Bicuspid Valve

Pathways of Circulation PULMONARY SYSTEMIC  Carries blood between HEART & ____________  O2 poor blood  Pulmonary Arteries to lungs  Returns oxygenated through Pulmonary Veins to heart  Carries blood from L.V. to the R.A. (TO BODY CELLS)  O2 rich blood leaving the heart  Supplies every organ with blood, including heart

Blood Vessels! Blood: heart → body Tough and flexible O2 RICH blood except… Largest Artery? Capillaries – thin vessels, O2 and nutrients diffuse into tissues; single file Blood: body → heart Thinner and less elastic O2 Poor Large veins contain valves Muscles contract to move blood

What is Blood Pressure?  Define: “[the] pressure that is exerted by the blood upon the walls of the blood vessels”  Blood Pressure is measured by the Systolic Pressure over the Diastolic Pressure.  For example, the average healthy teen or adult has a blood pressure below 120/80 and above 100/65  Systolic Pressure is the fluid pressure of a contracted blood vessel.  Diastolic Pressure is the fluid pressure of a relaxed blood vessel.

HIGH BLOOD PRESSURE 140/90 and above  High Blood Pressure, or Hypertension, is a problem that many people suffer from and do not even know, because it often has no symptoms  High Blood Pressure can cause:  Heart damage due to the need for the heart to work harder  Tears in blood vessels  Heart attack  Stroke  Kidney Damage

LOW BLOOD PRESSURE 90/60 and Below  Low Blood Pressure, or Hypotension can cause:  Kidney Failure  Dehydration  Dizziness  Syncope (fainting)