The Cardiovasuclar System Flashcards
(103 cards)
What are the three main components?
- blood
- blood vessels
- heart
What term can be used interchangeably with the cardiovascular system?
Circulatory system
What do cells need?
Oxygen and nutrients
What challenge is solved by having a cardiovascular system?
Diffusion is too slow
What are the functions?
- Transport gases, nutrients, hormones and waste
- regulation: blood regulates PH and body temperature
- protection against blood ????
What are arteries?
Carry blood away from heart, carry high pressure blood
Arterioles
Smaller branches of artists, walls are less thick
Capillaries
One cell thick (epithelium) site of gas exchange by diffusion
Venules
Small veins, transport blood from capillary blood to veins
Veins
Pump blood to heart, have valves, looser so they can expand more
What are the blood vessel layers?
Tunica interna (Endothelium and connective tissue) Tunica intermedia/middle sheath (smooth muscle and connective tissue) thicker in arteries Tunica externa ( connective tissues)
Define precapillar sphincter
Circular muscle that controls blood flow
What is the heart?
A cone shaped muscle organ about the size of a fist
Myocardium
Major portion of the heart that consists if cardiac muscle tissue
Pericardium
A thick serous membrane that secrets a small quantity of lubricating liquid (to prevent friction)
Ventricles
Pump blood to lungs and body
What are the two valves that lay between the atria and the ventricles called?
Atrioventricular valves
What are the strong fibrous strings called in the heart that control the main valves?
Chordae tendineae
What is the pathway of blood through a loop?
leaves heart and pumps to the heart first, then the lungs, brain, and the rest of the body.
How are different vessels specialized?
Veins carry low pressure blood to the heart, and arteries carry high pressure blood away from the heart. Since it has to carry higher pressure blood, the arteries have thicker walls to prevent the vessel from popping.
How do closed and open systems differ?
open systems do not transfer gases.
How do single and double loops differ?
In a double loop, more oxygen can be carried to the body at one time since there are multiple routes for the blood to take.
what are the four properties of cardiac muscle?
Contractile, self-excitable, authorythmic, non-fatiguing.
Describe contractile:
When stimulated to do so, cardiac muscle cells can shorten themselves using motor proteins to contract the entire muscle.