The Heart and Blood Vessels Flashcards
What are the 3 major blood vessels?
Capillaries, veins and arteries.
What do valves do within the vessels?
prevent the back-flow of blood
What does the circulatory system do?
Transport O2, nutrients, hormones
Removes waste (CO2 and urea).
Why does the heart act like a pump?
So it can pump blood through the system.
Why does the human body have 2 circulatory loops?
Because a large amount of blood is needed and transported to the lungs, then the rest of the body.
What does the acronym LAB RAT stand for?
Left Atrium Bicuspid, Right Atrium Tricuspid.
What is the septum?
The thickest part in the middle of the heart that keeps the 2 bloods separate.
What does the pulmonary artery do?
Takes blood to the lungs.
What does the pulmonary vein do?
Takes blood to the heart.
Order of how blood travels through the heart…
Vena cava - right atrium - right ventricle - pulmonary artery - pulmonary vein - left atrium - left ventricle - aorta - septum
What do arteries have a thick outer layer of?
Collagen - maintains shape and volume of blood vessel.
Muscle - controls pressure of blood flow and contracts/relaxes to change size of lumen.
Elastic - stretches slightly to allow blood to pass through.
How thick are the capillaries?
Epithelium - 1 cell thick.
Lumen - 1 RBC thick.
What do capillaries form?
A capillary bed.
What do veins have a thick outer layer of?
Collagen - not as thick as artery outer layer.
What do veins have a thin outer layer of?
Elastic and muscle.
