Ch 11 Cardiovascular System

• cardiovascular system

  delivers oxygen and nutrients to cells of body tissue
• arteries

  vessels that lead away from the heart
• veins

  1. thinner walls than arteries
  2. move deoxygenated blood toward the heart from the tissues
• capillaries

  1. smallest vessels
  2. form the point of exchange for oxygen and nutrients into body cells/waste products coming from body cells
• tricuspid valve

  between right atrium and right ventricle
• pulmonary valve

  between right ventricle and pulmonary artery
• mitral valve

  between the left atrium and left ventricle
• aortic valve

  between left atrium and aorta
• diastole

  relaxation
• systole

  contraction
• what is the rate for diastole-systole cardiac cycle


  1. 70 to 80 times per minute (100,000) times per day
  2. pumps 3 ounces of blood with each contraction
  3. 5 quarts a minute
  4. 75 gallons an hour
  5. 2000 gallons a day
• lubb

  closure of the tricuspid and mitral valves at the beginning of systole
• dubb

  closure of the aortic and pulmonary valves at the end of systole
• murmur

  an abnormal heart sound caused by improper valve closure
• sinoatrial node (SA node)

  pacemaker of the heart
• pacemaker

  origin of electrical impulse causing walls of the atria to contract and force blood into the ventricles

  • ending diastole
• atrioventricular node (AV node)

  this sends the excitation wave to a bundle of specialized fibers called atrioventricular bundle or Bundle of His
• bundle of his

  helps form conduction myofibers that extend to ventricle walls and stimulate them to contract, beginning systole

  • short rest period follows
  • pacemaker begins wave of excitation again
• ECG or EKG

  electrocardiogram - record used to detect electrical changes in heart muscles as the heart beats
• P wave

  spread of excitation wave over the atria just before contraction
• QRS wave

  spread of excitation wave over the ventricles as they contract
• T wave

  electrical recovery and relaxation of the ventricles
• how is a heart attack recognized

  elevation in the ST segments of the ECG

  • MI = myocardial infarction
  • one type of MI is an S-T elevation MI or STEMI
• blood pressure

  force that blood exerts on arterial walls
• how is BP measured

  sphygmomanometer

  systolic pressure/diastolic pressure
• hypertension

  when BP > 140/90 mm Hg
• aorta

  largest artery in the body
• apex of the heart

  lower tip of the heart
• arteriole

  a small artery
• artery

  largest type of blood vessel

  • carries blood away from the heart to all parts of the body
• atrioventricular bundle (bundle of his)

  specialized fibers connecting the atria with the ventricles and transmitting electrical impulses between them
• atrioventricular node (AV node)

  specialized tissues in the wall between atria

  • electrical impulses pass from pacemaker through AV node and bundle of his toward ventricles
• atrium

  one of two chambers of the heart
• capillary

  smallest blood vessel
• carbon dioxide (CO2)

  waste gas released by body cells

  • transported via veins to the heart and then lungs for exhalation
• coronary arteries

  blood vessels that branch from the aorta and carry oxygen rich blood to the heart muscles
• deoxygenated blood

  oxygen poor blood
• diastole

  relaxation of the heartbeat
• electrocardiogram

  record of the electricity flowing through the heart
• endocardium

  inner lining of the heart