ANATOMY OF THE CIRCULATORY SYSTEM Flashcards
1/ Name the major arteries and veins (from the heart to the foot and back to the heart) 2/ Describe the layered structure of blood vessels 3/ Compare structure of arteries with that of veins 4/ Describe the structure of blood capillaries and contrast it with that of arteries and veins 5/ Describe, giving examples the 3 types of blood capillaries 6/ Name the major components of the lymph vascular system 7/ Describe the structure of lymph capillaries
which artery branches to become the right subclavian and right common carotid artery?
brachiocephalic
which arteries run along the inferior surface of the ribs?
intercostal
which artery branches into 2 from the aorta around the hip?
common iliac
which artery supplies the spleen, stomach and liver?
celiac trunk
which artery provides blood to the intestine?
superior and inferior mesenteric arteries
what is the point where the aorta branches into common iliac called?
aortic bifurcation
what artery runs along the thigh?
femoral
what artery runs across the knee?
popliteal
what arteries run along the legs’ calves?
posterior and anterior tibial
what is the main artery that runs to the foot to supply blood to there?
dorsalis pedis
where is superficial temporal artery located?
near the ear at temporal lobe
what artery at the forearm that you can use to detect pulse because it is close to the surface?
radial
which vein drains blood from legs and specifically feet to go back to heart?
saphenous
what are the 3 layers of a blood vessel from inner to outermost?
- tunica intima
- tunica media
- tunica adventitia (externa)
what are the 3 layers of tunica intima from inner to outermost?
- endothelium
- sub-endothelium
- internal elastic lamina (IEL)
what is endothelium of the tunica intima made of?
simple squamous epithelium
what is the purpose of the endothelium in tunica intima?
non-stick surface that lines all the lumen of vessels to prevent blood coagulation
what is the sub-endothelium of the tunica intima made of and what does it do?
sparse pad of loose FCT to cushion the endothelium
what is the characteristic of internal elastic lamina?
condensed sheet of elastic tissue (elastin) which is well developed in arteries and less developed in veins
what is the tunica media of blood vessels made of?
smooth muscle
why is the tunica media made up of smooth muscles?
for involuntary control and non-striated
why is scaffold structure presented in tunica media?
because tunica media has a variable content of connective tissue fibres which is mainly collagen and elastin
_______(1)_______ has the thickest tunica media while _______(2)________ has the thickest tunica adventia
(1): arteries
(2): veins
what does compliance mean?
stretchiness
what is abundant in the tunica adventitia layer of blood vessels?
- loose FCT
- collagen and variable amount of elastin
what special structure can also be found in larger vessels?
- vasa vasorum
- little vessels to supple and drain the large vessels
what other structure can you find in the tunica adventitia region?
lymphatics and autonomic nerves
what is the function of arteriole?
the resistance vessels of the circulation –> determin blood pressure
why is it important for veins to have a much higher compliance than arteries?
veins contains a large volume of blood flow in small pressure, therefore it needs to be more stretchy than artery so that it can ‘inflate’ to have that large volume of blood flow
why is the vein wall appears to be thin and wrinkly?
- thin: thinner media with only a few layers of smooth muscle, adventitia thickest layer due to capacitance function –> sustainable hold the large volume of blood
- wrinkle: thin wall –> tissues surrounded falling on –> collase
why does veins need valves?
unidirectional and anti-gravitational blood-flow in low pressure –> valve assures there are no backflow of blood
what is vein with leaky valve called?
varicose vein
how does skeletal muscle assist the unidirectional bloodflow?
muscle contracts –> squeeze the leaflet and close the valve
what is the major function of capillaries?
site of exchange between blood and tissues
capillaries’ function demands _______1_______ for a better exchange with minimal barrier, a _______2_______ of the capillary bed as well as a _____3______ and ______4_______ blood flow a.k.a pulsatile flow for efficiency
1: very thin wall
2: large total cross-sectional area
3: smooth
4: slow
how is the blood flow in capillary bed is much slower compare to as such in arterioles?
the large total area
how does a 1 single RBC/flow reflect the ultrastructure of capillary?
- use RBC to estimate the diameter of lumen within capillary
- cell allows 1rbc/flow for an effective exchange of O2 since rbc push against the wall –> optimal distance with wall
what is the type of intercellular junction you can find in capillary wall?
tight junction
which specialised structure you can find at the beginning of the capillary bed and what is that structure made of?
- precapillary sphincter
- constrict and relaxed to control and directly communicate between capillary bed and terminal arteriole
- made up of smooth muscle cells –> involuntary
what are the 3 types of capillary?
- continuous
- fenestrated
- sinusoidal
does capillaries have 3 layered wall like arteries and veins?
- no
- only tunica intima, no media or adventitia
- instead appears to have a basement membrane made up of mainly collagen
what is the most widespread capillary?
continuous
what is the leakiest type of capillary?
sinusoidal
what is the diameter of continuous and fenestrated capillary?
8-10 micrometer
what is the diameter of sinusoidal capillary?
-40 micrometer
what is a special structure that you can fine on the continuous capillary wall, fenestrated and sinusoidal?
- intercellular cleft on continuous
- fenestration (physical pores for filtration) on fenestrated
- intercellular gap
which type of capillary has an incomplete basement membrane?
sinusoidal
where can you find:
1: continuous capillary?
2: fenestrated capillary?
3: sinusoidal capillary?
1: skeletal and cardiac muscle
2: kidney, small intestine
3: liver
which structure does the lymph system ‘unite’ with?
veins and capillaries
what are the 4 functions of the lymph system?
1/ drains excess tissue fluid and plasma proteins from tissues and returns them the blood
2/ filters foreign material from the lymph
3/ ‘screens’ lymph for foreign antigens and responds by releasing antibodies and activated immune cells
4/ absorb fat from intestine and transport to blood
where does the lymphatic system begin?
commence as large, blind-ending capillaries
what is the name of the special group of lymphatic vessels from small intestine? what does that group do?
- lacteals
- drain fat-laden lymph into a collecting vessel
what is the name of the collecting vessel that the lacteals from small intestine drain to?
cisterna chyli - a dilated sac of thoracic duct
large collecting vessels also contain ______________ to prevent backflow at low pressure
valves
what is the special structure of lymph vessel that is different from other vessels?
- thin wall
- no rbc
what are the name of the 3 main lymph nodes?
- cervical nodes
- axillary nodes
- inguinal nodes
what does right lymphatic duct (cervical and axillary nodes) drains into?
right subclavian vein
what does thoracic duct and everywhere else except lymphatic duct of cervical and axillary drains into?
left subclavian vein
what do afferent and efferent lymphatic vessels do to the lymph nodes?
- afferent: brings fluid to node
- efferent: takes fluid away from node
how is metastatic cancer from breast cancer form?
breast tissue lymphatic drainage can carry cancer cells into the blood vascular system
