Transcript Chapter 15x
CHAPTER 15 Cardiovascular, Respiratory and Digestive Systems WHY THE BLOOD CIRCULATES • Provides nutrients and oxygen, carries away waste and helps fight disease Tasks Accomplished • Carrying oxygen from lungs to body cells • Absorbing nutrients from food and delivering them to body cells • Carrying carbon dioxide from your cells back to your lungs • Delivering other waste products to the kidneys for removal • Helping white blood cells fight disease BLOOD CIRCULATION • Heart, blood and blood vessels • 4 chambers; 2 atria and 2 ventricles • Blood moves from the atria to the ventricles • Ventricles contract to pump blood out of the heart BLOOD • 55% of blood is PLASMA- fluid in which other parts of the blood are suspended • 40% of blood contains red blood cells that contain HEMOGLOBIN- the oxygen-carrying protein in the blood • White blood cells protect against infection • PLATELETS- types of cells in the blood that cause blood clots to form • 4 blood types; A, B, AB and O • Type O is a “universal donor” BLOOD VESSELS • Arteries carry oxygenated blood away from the heart and branch into smaller arterioles • CAPILLARIES- small vessels that carry blood from arterioles and to small vessels called venules, which empty into veins • Veins- blood vessels that return blood to the heart https://youtu.be/oHMmtqKgs50 CIRCULATORY SYSTEM HEALTH • Eat a well-balanced diet • Maintain a healthy weight • Aerobic exercise for 30 minutes, 3-4 times a week • Avoid secondhand smoke and tobacco products • Get regular medical check-ups BLOOD PRESSURE- measure of the amount force that the blood places on the walls of blood vessels, particularly large arteries, as it is pumped through the body • Systolic- the maximum pressure (top number) • Diastolic- the pressure at its lowest point (bottom number) • 120/80 CARDIOVASCULAR SYSTEM PROBLEMS • Congenital Heart Defects- heart conditions that are present at birth • Heart Murmurs- caused by a hole in the heart, or a leaking valve • Varicose Veins- valves in veins not closing tightly enough to prevent backflow • Anemia- loses ability to to carry oxygen rich blood (low iron) • Hemophilia- blood does not clot properly (inherited) • Leukemia- form of cancer where white blood cells are overproduced