Introduction to CVS Flashcards
Why do we need a CVS?
- Temperature regulation
- Pump blood through the lungs and carry oxygen
- Transport nutrients to muscles and organs
- Circulates hormones and immune mediators
- Connection to the lymphatic system
- Human reproduction
What is passive diffusion?
Is the random undirected thermal movement of molecules
the relation between time of diffusion and distance
t ∝d^2
What does the CVS use
CVS uses convection to provide fast and directional transport
What does the heart create and using what in convection formation?
The heart creates a pressure gradient using metabolic energy
What does output of blood from the heart create?
The output of blood at high pressure creates a pressure difference with distant blood vessels
Average pressure in aorta
> 100 mmHg
Average pressure in vein
5-10 mmHg
What does pressure difference drive?
Pressure difference drives blood flow
Systole
Contraction
Diastole
Relaxation
What are the brain and myocardium usually regarding cardiac output?
Myocardium and brain are relatively under perfused
Why does the under perfusion of myocardium and brain lead to clinical problems?
Can lead to angina, stroke
Equation of cardiac output
Cardiac output=Heart rate x stroke volume
What is the cardiac output?
Volume of blood expelled from the left ventricle per minute