flow of blood

• 1. deoxygenated blood from the upper and lower body flows through the superior and inferior vena cava
• 2. the superior and inferior vena cava empty blood into the right atrium
• 3. blood from the right atrium passes through the tricuspid valve
• 4. blood passes through the tricuspid valve into the right ventricle
• 5. blood from the right ventricle passes through the pulmonary semilunar valve
• 6. blood flows through the pulmonary semilunar valve into the right and left pulmonary arteries
• 7. pulmonary arteries take blood to the lungs for gas exchange
• 7. blood becomes oxygenated
• 8. right and left pulmonary veins bring blood back to the heart
• 9. pulmonary veins empty blood into the left atrium
• 10. the blood from the left of the atrium flows through the mitral or bicuspid valve
• 11. after passing through the mitral valve, blood enters the left ventricle
• 12. blood from the left ventricle passes through the aortic semilunar valve
• 13. after passing through the aortic semilunar valve, the blood enters the aorta and is then pumped to the rest of the body
• pulmonary circuit: blood from the heart to the lungs and back to the heart
• systemic circulation: blood from the body to the heart and back to the body
• systole - contract
• diastole - relax
• the heart will still beat even outside of the body because of the characteristic called myogenic control, its is caused by an electrical signal from within heart muscle itself
• electrical system aka the cardiac conduction system
• sinoatrial node - SA
• atrioventricular node - AV
• bundle of his and purkinje fibers
• congestive heart failure - the heart is too weak or stiff to pump blood effectively
• myocardial infraction heart attack - coronary artery is blocked so blood cannot supply the heart with oxygen
• atrial fibrillation - cause irregular beat
• • ways to prevent heart disease - don't smoke or use tobacco, exercise 30 minutes a day, eat a heart healthy diet