Lecture 25: Intro to Cardiovascular System Flashcards
1
Q
CVS functions
A
- Transport medium
- Body volumes
2
Q
CVS as a transport mechanism
A
- Respiratory gases (oxygen, CO2)
- Nutrients
- Metabolites
- Vehicle for hormones, vitamins, enzymes
- Heat distribution
3
Q
CVS Body volume distribution
A
- 60% body weight is water (42L in average 70Kg male)
- 60% (25L) intracellular
- 30% (13L) interstitial
- 7% (3L) plasma
4
Q
Total blood volume
A
- 5L total
- 3L plasma
- 2.5L intracellular water
5
Q
Components of the CVS
A
- Heart (cardio)
- Vascular
6
Q
Parallel circuits of CVS
A
- Left heart and systemic circuit
- Right heart and pulmonary circuit
7
Q
Consequences of parallel arrangement
A
- All organs receive blood of identical composition (arterial blood)
- Flow through organ can be controlled independently of flow through other organs
- Heart generates flow by imparting potential energy to build pressure
- Potential energy (pressure) can be converted to kinetic for bulk flow
- Flow = bulk transport process following fluid mechanics
8
Q
Vasculature consists of
A
- Arteries
- Arterioles
- Capillaries
- Veins
9
Q
Arteries
A
- Main conduits
- Pressure storers
10
Q
Arterioles
A
- Resistance vessels
- Regulate organ resistance and blood flow
- 50% of total resistance
11
Q
Capillaries
A
- Channels where exchange occurs between blood and interstitial fluid spaces
- Also have significant resistance
12
Q
Flow in L/R circuit
A
- Flows are equal
- Q from right heart (cardiac output) equal to Q from left heart
13
Q
Systemic circuit
A
- High resistance
- High pressure
- Total resistance about 4 times that of pulmonary circuit
14
Q
Pulmonary circuit
A
- Right heart needs to develop only 25% of pressure developed in left heart
- Low pressure circuit
15
Q
Priorities of the CVS
A
- Maintain constant blood flow to brain/heart
- Accomplish this via control system monitoring/regulating arterial pressure
