05 - Cardiovascular system: introduction Flashcards
List some of the key functions of the cardiovascular system…
- Provides controlled and continuous flow of blood
- Transport (hormones, nutrients, metabolic products)
- Homeostasis (heat distribution, pH, osmolarity)
- Immune defence
The CVS is organised as two circulations in series, served by…
Two pumps in series
Unidirectional flow through the CVS is ensured by the presence of…
Valves
Name the four valves of the heart…
Antrioventricular valves
- Tricuspid (R)
- Biscuspid or Mitral (L)
Semilunar valves
- Pulmonary (R)
- Aortic (L)
Define: Stroke volume (SV)
The volume of blood pumped by one ventricle (which is roughly 75ml at rest, on average)
Define: Cardiac Output (CO)
CO = Heart rate x SV
CO at rest is, on average, 5L/min.
Define: Venous Return (VR)
The amount of blood returning to the heart, which under steady state conditions is equal to the cardiac output (CO))
The vascular system is comprised of 4 types of vessel…
- Arteries
- Arteriolar
- Capillaries
- Veins
Arterial walls are:
A) Elastic
B) Thin
C) Have valves
D) All of the above
A) Elastic
Arterioles have lots of smooth muscle. They are high resistance vessel which control…
Blood flow to tissues
Capillaries are thin walled vessels adapted for…
Exchange
Veins are…
A) High pressure vessels with valves
B) Low pressure vessels with valves
C) High pressure vessels without valves
D) Low pressure vessels without valves
B) Low pressure vessels with valves
The greatest pressure drop in the cardiovascular system occurs as blood moves through the…
Arterioles
Pressure in the large arteries is ( constant / pulsatile )…
Pulsatile
Blood flow in vessels is proportional to…
Pressure gradient
