KINE 2P90 Quiz 1

• Cardiovascular System Maintains Homeostasis by:

  • Transporting O2 to tissues
  • Transporting CO2 away from tissues
  • coupled to respiratory system
  • Transporting nutrients to tissues
  • Regulating body temp
• The Cardiovascular System during Exercise

  • the demand for O2 increases by 10-20 fold
  • changes in cardiac output and blood flow distribution
  • key factors for increasing Vo2
• Structural Comparison of Cardiac and Skeletal Muscle

  • Nuclei: is single celled in cardiac but multiple in skeletal
  • Cellular Junction: is present as intercalated discs in heart muscle and not present in skeletal muscle
  • Connective Tissue: Is Endomysium in heart muscle and Epimysium in Skeletal muscle
  • Shape: heart muscles are shorter fibres that contain branching
• Function of Intercalated Discs:

  • cardiac muscle works like a single giant cell
  • intercalated discs interconnect myocytes
  • facilitates spread of electrical activity
  • As well as hormones and other chemical signals
  • Called a functional Syncytium
• Layers of Heart Wall:

  1. Epicardium
  2. Myocardium
  3. Endocardium
• Characteristics and Functions of Epicardium:

  • Serous membrane including blood, capillaries, lymph capillaries, and nerve fibres
  • Function: serve as lubricative outer covering
• Characteristics and Functions of Myocardium:

  • Cardiac muscle tissue separated by connective tissues and including blood capillaries, lymph capillaries, and nerve fibers
  • Function: Provided muscular contractions that eject blood from the heart chambers
• Characteristics and Functions of Endocardium:

  • Endothelial tissue and a thick sub endothelial layer of elastic and collagenous fibers
  • Function: Serve as protecting inner lining of the chambers and valves
• Pulmonary Circulation (~15mmHg) :

  • A low pressure system because pulmonary system offers very low resistance to blood flow
• Systemic Circulation (90-100mmHg):

  • A high pressure system because systemic system presents high resistance to blood flow; a regulated pressure system
• Pulmonary and Systemic Circulations:

  • The cardiovascular system actually consists of two entirely separate circuits
  • each side has equal flow(=cardiac output)
  • heart does not store blood
• Cross-sectional view of the heart:

  • in reality the Left ventricle wall is much thicker than right ventricle wall
  • there's a difference in pressure because the left ventricle pumps against pressure
  • hypertrophy also contributes to the LV wall being thicker
• The Heart Consist of:

  • 4 chambers
  • Right atrium
  • right ventricle
  • left atrium
  • left ventricle
  • 2 on the right side and 2 on the left side
  • also top and bottom parts (atria collects blood and ventricles eject blood)
• Right side of the Heart:

  • Carries deoxygenated blood in from superior vena cava to the right atrium through the tricuspid valve into the right ventricle up the pulmonary valve and out the pulmonary artery
• Left side of the Heart:

  • carries deoxygenated blood in through the pulmonary veins down the left atrium via the mitral valve into the left ventricle through the aortic valve up the aorta and out
• Valve System:

  1. Tricuspid valve (RA-RV)
  2. Semilunar valve (RV -PA)
  3. Bicuspid valve (LA-LV)
  4. Aortic Valve (LV-Aorta)
• Veins:

  • carry blood to heart
• Arteries:

  • carry blood from heart
• Flow of Blood:

  1. superior and inferior vena cava
  2. right atrium
  3. right ventricle
  4. pulmonary artery
  5. lungs
  6. pulmonary vein
  7. left atria
  8. left ventricle
  9. aorta
  10. tissues
• how does the hear itself get O2?

  • via coronary arteries
  • great genetic variation
  • number and route
• The Cardiac cycle:

  • Systole
  • Diastole
• Systole:

  • is ventricular contraction phase
  • ventricles expel blood