Lust-1

Question 1

Late Ventricular Diastole

Answer 1

• All chambers are relaxed
• ventricular P< Atrial pressure
  
  • AV valve opens
• Ventricles passively refilled
  
  • majority of ventricular volume

Question 2

Atrial Systole

Answer 2

• Ventricular Pressure< Atrial Pressure
• Atria contract -“Atrial kick”
  
  • finish filling the ventricles
• P wave marks the start of atrial systole

Question 3

Isovolumic ventricular contraction

Answer 3

• Ventricles start to contract (1st phase)
  
  • Ventricles P low bc we’ve been filling
  • AV valve closes=S1
  • haven’t developed enough P to open semilunar valves
• Ventricles sealed
  
  • ventricles contract
  • rapid increase in Pressure

Question 4

Ventricular Systole

Answer 4

• Ventricles Pressure continues to rise until we exceed arterial/aortic P
• Semilunar valve opens
• Blood ejected into pulmonary or aorta

Question 5

Isovolumic ventricular relaxation

Answer 5

• Ventricles relax/expand
• ventricular pressure decreases
  
  • less than arterial pressure
• Semilunar valve closes=S2
• ventricles sealed
• Ventricles relax and pressure decreases rapidly

Question 6

What regulates blood flow?

Answer 6

• Blood pressure
• Vascular resistance

Question 7

Distribution of water

Answer 7

1. Intracellular compartment (67%)=2/3
2. Extracellular (33%)=1/3
   
   1. Extravascular (interstitial=27%)
   2. Intravascular (6%)
      
      1. plasma volume supplies the heart