CIRCULATORY SYSTEM: Blood Vessels Flashcards
5 main types of blood vessels
Artery, Arterioles, Capillary Venules, Veins
Arteries location and structure
Smooth muscle
internal elastic membrane
run deep along bones
Arteries function
transport blood away from heart
walls expand to accommodate high BP
Creates pulse feeling
Arterioles location and structure
Smaller than arteries
thinner walls
have pre-capillary sphincters to regulate blood flow
lead to capillaries
Arterioles function
Controls blood flow to capillaries
pre-capillaries sphincters regulate blood flow and BP
Capillary location and structure
Very thin walls
site of capillary-tissue fluid exchange
all over body
Capillary function
Connects arteries to veins
Venules location and structure
thinner walls than veins and arteries
near surface
Venules function
drains blood from capillaries and takes blood to veins
Veins location and structure
Inelastic walls
contain 1 way valves
near surface usually
Veins function
Transport blood to heart
BP much lower than arteries
valves prevent blood from going backwards
skeletal muscles squeeze blood along
What is the capillary-tissue fluid exchange?
Exchange due to difference in BloodP and OsmoticP
What happens at the arteriole side during C-T exchange?
(40) BP>OP(25)
- BP forces water out of the blood into extracellular fluid (ECF)
- Water carries with it the O2 and nutrients (from digestion)
- intestinal fluid diffuses into body cells due to increase of O2 and nutrients
What happens at the Venule side during C-T exchange?
OP (25)>BP(10)
- due to lack of H2O, blood becomes very concentrated therefore the venule side has great osmotic pressure
- OP forces H2O back into blood
- H2O carries CO2 and metabolic waste from extracellular fluid into blood
- carried into kidneys and other excretory organs to be removed
functions of lymphatic system?
Take up excessive tissue fluids from ECF Transport fatty acids and glycerol from intestines to subclavian vein Fight infection Trap and remove cellular debris
