cardiovascular system; transport vessels Flashcards
transport vessels
mammalian circulatory system includes:
arteries
veins
capillaries
arteries function
carry oxygenated blood away from the heart
artery exception
pulmonary artery -> carry deoxygenated blood
artery outer layer
made up of connective tissues + few elastic fibers
artery middle layer
thickest + most distinguishable made up of circular bands of smooth muscle
artery inner layer
only once cell thick + made up of smooth epithelial cells
layer function
elasticity allows artery to first expand as blood passes through and then snap back again
layer function cont.
movement keeps blood flowing in the right direction + provides additional pumping motion to help force blood through the vessels.
ma. aorta
largest artery- 2.5 cm in diameter
transports large volumes of O2/rich blood
from heart -> other arteries/parts of body
ma. brachiocephalic vessel
“arch” where the aorta branches into the carotid arteries
ma. carotid
supplies blood to neck + head
ma. vertebral
supplies blood to spinal cord
supply blood -> arms
subclavian
axillary
radial
ulnar
supply blood -> legs
iliac arteries
femoral arteries
pressure triggers heart…
for artery to expand and contract
what allows for diffusion
capillaries
ma. coronary arteries
supply blood -> heart
ma. celiac trunk
abdominal branch of the aorta
many arteries feeding digestive system are connected here
ma. hepatic arteries
supply blood to liver
ma. renal arteries
supply blood to kidney
ma. gastric arteries
supply blood to stomach
ma. mesantric arteries
supply blood to small + large intestine
veins
carry deoxygenated blood towards the heart
vein exception
pulmonary vein
carries blood from lungs -> heart
vein characteristics
thinner middle-layer wall, huge lumen
veins problem + solution
veins cannot contract
veins use valves to keep blood flowing to
heart
regions above heart -> pull of gravity
draws blood through the veins
valves
aids when blood is in regions below heart, the valves/skeletal muscle contractions
-> exert pressure on vessels lying between
them
-> force blood up to heart
prevent blood from flowing one direction
veins are equipped with one-way valves -> prevent backflow
capillaries (practically a epithelial cell)
walls are only one cell thick + diameter is just large enough for the largest blood cells to pass single-file
wall of capillary regulates what?
movement of materials into + out of blood stream
diffusion can only go across
one cell
capillaries most commonly found
nails, face
diffusion
movement of molecules under a concentration gradient of high to low concentration.
