Heart and CVS Flashcards
The function of cardiovascular system ?
- Mass flow system to transport (Hormones)
- temperature regulation
Function of the heart ?
- Large blood supply
- Atria and ventricle on each side separated by a central septum
- Unidirectional flow results from one-way valves
What does sinoatrial node(SAN) do ?
initiating electrical impulses to stimulate contraction
What are the 3 layers of the heart wall ?
Epicardium
Myocardium
Endocardium
Why is myocardium important ?
Possess many mitochondria and myoglobin to produce ATP
What is a sarcomeres ?
it’s a muscle fiber that is composed of two main protein filaments actin and myosin filaments
What are blood vessels ?
channels that carry blood throughout the body.
3 different types of blood vessels ?
Arteries
Veins
Capillaries
The function of arteries ?
thick elastic and smooth muscle walls to maintain blood pressure around the body
The function of veins ?
Veins have low resistance and one way valves.
The function of capillaries ?
-Exchange of materials in capillary beds
- endothelial layer on the basement membrane
- Large surface area and thin diffusion barrier
What does elastic recoil in arteries do ?
maintains blood pressure and movement of blood
How does blood flow occur ?
One-way valves prevent backflow
After systole the elastic walls of the chambers recoil drawing blood in from the veins
How is blood flow controlled ?
Regulation of blood pressure by vasoconstriction and vasodilation signalling to smooth muscle within vessel walls
What is vasoconstriction ?
the narrowing of blood vessels by small muscles in their walls.
What is vasodilation?
the widening of blood vessels because of the relaxation of the blood vessel’s muscular walls.
The factors of blood pressure occur in arteries?
force created by heart pumping
volume of circulating blood
size of blood vessels
What is systolic pressure?
Systolic pressure is the pressure in arteries during the contraction of heart muscle
What is pulmonary pressure ?
pulmonary pressure works against gravity to push blood to the whole head and body
