cardiovascular and respiratory system

• what is the function of the cardiovascular system?

  transports blood between body cells and organs
• what are the parts of the cardiovascular system?

  heart, arterioles, capillaries, veins
• what are the 2 divisions of the cardiovascular system?

  Pulmonary = eliminates carbon dioxide via lung +oxygenates blood Systemic = delivers oxygen to all body cells and carries away waste
• heart is enclosed by a double layered

  pericardium
• what is the function of the fluid in the pericardial sac

  reduces friction between pericardial membranes as the heart moves within them
• epicardium

  outer layer; reduces friction
• myocardium

  middle layer; muscle tissue that pumps blood out of heart chambers
• endocardium

  inner layer; epithelium and connective tissue; contains blood vessels and purkinje fibers
• fibrous pericardium

  toughest outermost layer of actual heart; prevents heart from expending too much
• parietal pericardium

  line the inside of the fibrous pericardium
• pericardial cavity

  mechanical protection for the heart and big vessels
• coronary blood vessels

  on top vessels, supply O2 to heart
• List the chambers of the heart.

  right left atria, right left ventricles
• what vessles take blood to the right atrium

  superior vena cava + inferior vena cava, coronary sinus, tricuspid valves
• what vessels take blood to the left atrium

  mitral valve, pulmonary veins
• trace the path of blood through the heart, include valves

  deoxygenated blood flows from vena cava into right atrium

  passes through the tricuspid valve into the right ventricle

  passes through the pulmonary valve into the pulmonary artery

  travels to the lungs to be reoxygenated

  the blood travels from the lungs through the pulmonary veins into the left atrium

  then the mitral valve

  then the left ventricle

  then the aortic valve

  aorta

  oxygenated blood is sent out to the rest of the body.
• what is the function of valves

  prevent the backward flow of blood
• the cells of the heart are supplied with blood via the

  coronary vessels
• how does the heart maintain a constant supply of oxygenated blood to itself?

  coronary artery branches off aorta
• What events make up a cardiac cycle?

  atria contract (atrial systole) while ventricles relax (ventricular diastole). then, ventricles contract (ventricular systole), while atria relax (atrial diastole)
• what produces the heart sounds heard through a stethoscope?

  due to vibrations produced when valves close
• describe the characteristics of cardiac muscle fibers. include functional syncytium


  connect to form functional syncytium, structure contracts as a unit
• trace an impulse through the cardiac conduction system

  sa node, atrial syncytium, jet fibers, av node, av bundle, bundle branches, purkinje fibers, ventricular synctium
• how is a cardiac impulse initiated

  SA node (pacemaker)
• what is an electrocardiogram

  recording of electrical changes in myocardium
• Describe how the sympathetic and parasympathetic systems regulate heart function

  sympathetic = norepinephrine, decrease heart rate

  parasympathetic = acetylcholine, increase heart rate
• what is the baroreceptor reflex

  increase or decrease the heart rate accordingly; helps to maintain blood pressure at nearly constant levels,
• How is the heart affected by changes in potassium and calcium levels?

  potassium = repolarization close Na channel, opens K channel

  calcium = binds with troponin so actin + myosin can bind; influx into axon to send out neurotransmitters
• hyperkalemia


  excess K+ ions decrease rate and force of contractions
• hypokalemia


  deficient K+ ions may cause abnormal heart rhythm
• hypercalcemia


  excess Ca2+ increase heart actions, dangerous extended heart contraction
• hypocalcemia


  deficient Ca2+ ions depresses heart action
• Describe the closed circuit formed by blood vessels

  .

  
• Describe the wall of a typical artery.

  strong and elastic; 3 layers: Tunica interna, Tunica media, and Tunica externa
• What is the role of smooth muscle in the arterial wall?

  contraction
• How is the structure of an arteriole different from that of an artery?

  thinner, but same layers
• What controls the diameter of the arterioles and what do changes in diameter effect?

  vasoconstriction: small diameter = small blood flow

  vasodilation: large diameter = more blood flow
• Describe the mechanisms that limit or prevent coagulation

  
  

  coagulation, is an important process that prevents excessive bleeding when a blood vessel is injured.
• Describe the mechanisms that limit or prevent coagulation (blood clotting)

  hydration, movement, low cholesterol
• Describe the structure of capillaries. What is the function of capillaries?

  smallest, 1 RBC Wide, one cell layer

  fx: site of exchange (nutrients, gas, waste)