A + P Cardiovascular System Flashcards
main purposes of the cardiovascular system
delivery of oxygen, nutrients, hormones, etc. to tissues via the blood circulation
removal of CO2, waste products, metabolic intermediates, etc. from the tissues via the blood circulation
CVS main components
blood
vessels
heart
blood function
serves as the medium for delivery
vessels function
pathways for the blood
heart function
pump for the blood
blood functions
transportation of nutrients, hormones, O2 and CO2, and waste products within the body
regulation of pH and ions within the body
restriction of fluid losses at injury sites
defense against toxins and pathogens
stabilization of body temperature
blood tissue type
specialized connective tissue
whole blood composition
plasma -albumens -globulins -fibrinogen formed elements
plasma composition
fluid consisting of water, dissolved plasma proteins and other solutes
formed elements composition
-specifics
cells and solids
- red blood cells - 99.9%
- white blood cells - <0.1%
red blood cells function
-special note
transport O2 and CO2 on hemoglobin
special
-surface antigens on RBCs determine blood type A, B, AB, or O
white blood cells function
part of the immune system
platelets function
cell fragments involved in clotting
blood characteristics
sticky
three layers of blood vessels
tunica intima
tunica media
tunica externa
tunica intima location and composition
innermost endothelial lining
tunica media location and composition
middle layer
contains smooth muscle
tunica externa location and function
outermost layer
anchors vessels to adjacent tissues
vessels can contract/relax, which is called
vasoconstriction/vasodilation
vessel categories
arteries arterioles capillaries venules veins
arteries
characteristics
largest vessels for systemic blood delivery
have thick, muscular walls and are highly elastic to withstand high pressures
-no gas exchange can occur
arterioles
characteristics
smaller branch of arteries
have thin but muscular walls that can contract to direct blood flow
capillaries
characteristics
smallest vessels
thin walls permit gas exchange
no muscle control blood flow
venules
characteristics
smaller branch of veins
thin, compliant walls help store a lot of blood
one-way valves facilitate blood flow
veins
characteristics
largest vessels for systemic blood return
have compliant, muscular walls
one-way valves to store and/or pump blood back to the heart
heart
- function
- location
pump for the blood and connects with the vessels to distribute blood around the body
sits between two pleural cavities in the mediastinum
heart layers
pericardium
epicardium
myocardium
endocardium
pericardium function
covering for the heart
function
-a sac-like structure that surrounds, lubricates, and protects the heart and root of the great blood vessels
comprised of two layers
pericardium two layers
parietal pericardium
-outer layers
visceral pericardium
-inner layer
epicardium
-function
outer layer
function
-responsible for producing the pericardial fluid
myocardium
functions
middle layer
functions
-primary muscle tissue of the heart
-contains short, branched, single-nucleated cells (myocytes)
myocyte functions
-control type
utilize gap junctions (intercalated discs) to propagate electrical signals quickly for synchronized cardiac contraction
-involuntarily and automatically controlled
endocardium
- composition
- functions
inner layer
comprised mostly of epithelial cells to create a smooth lining inside the chambers of the heart
creates an ionic barrier between blood and cardiac tissue
heart chambers
right atrium (RA) right ventricle (RV) left atrium (LA) left ventricle (LV)
right atrium
-function
collects de-oxygenated venous blood from systemic circulation via the superior and inferior vena cava and pumps it into the right ventricle
right ventricle
-function
receives de-oxygenated blood from the right atrium and pumps it through the pulmonary artery to the lungs