Tissues + Structures - Blood vessels and Lymphatics Flashcards
Do vessels have different origination?
Yes.
What is a feature of vessels in embryology?
Some vessels supplying an organ can migrate far from its origination.
What happens in the gonad vessels?
These vessels may elongate to reach the organ.
What happens with the kidney vessels?
New vessels appear, replacing the old ones as the organ migrates.
Where do the vessels supplying the kidney originate from?
The pelvic brim - supplied by the prolongation of the dorsal aorta - median sacral artery.
What is the pathway of the vessels that supply the kidney?
As the kidney goes up the posterior abdominal wall, it is supplied successively from internal and common iliac arteries. Then supplied by series of branches from the abdominal aorta.
What are abnormal renal arteries?
One or more aortic branches.
Are veins bigger than their corresponding arteries?
Yes.
What is the reason that veins are bigger than their corresponding arteries?
Rate of flow in veins is slower.
How does blood flow in veins in the foot and hands?
Via the dorm - to avoid the pressure of the palm and sole, this would construct the veins.
What are venae comitantes?
A pair of veins - normally seen in peripheral limbs.
What happens in proximal limb veins?
The venae comitantes unite into a single large vein e.g. axillary and popliteal.
Why do large veins have big space around them?
To allow for great dilatation during increased blood flow.
Where does the axillary vein lay?
In front of the pre-vertebral and axillary fasciae.
Where does the femoral vein lay?
Alongside the femoral canal.
Describe the internal jugular vein and the carotid sheath?
The carotid sheath sits loosely around the IJV.
Describe the carotid artery and the carotid sheath?
Carotid sheath sits tightly around the artery.
Where do the pulmonary veins lay?
Lower part of the lung root - this is to allow for expansion of the vein between the two lax layers of the pulmonary ligament.
What does the dead space alongside large veins contain?
Regional lymph nodes e.g. deep inguinal nodes alongside the femoral vein.
What are the smallest vessels?
Capillaries.
What do capillaries consist of?
Flattened endothelial cells.
What are the layers of other vessels?
Three layers:
1. Tunica intima (innermost).
2. Tunica media.
3. Tunica adventitia (outermost).
What does the tunica intima consist of?
Endothelial lining with a variable amount of underlying CT.
1. Endolthelium.
2. Basement membrane.
3. Subendothelial CT.
4. Internal elastic membrane.
Describe tunica intima layer in the artery?
Has an internal elastic lamina - this gives a crenated appearance to the lumen of the artery.
What are the types of arteries?
- Elastic.
- Muscular.
- Arterioles.
What does the tunica media consist of?
Circular smooth muscle fibres and there is an external elastic lamina at the junction of the media and adventitia.
Describe the tunica media in large vessels like the aorta and their branches?
They have a large amount of elastic tissue mixed with muscle fibres.
Describe the tunica media in veins?
Thinner.
Describe the tunica intima layer in veins?
There is no internal elastic lamina.
Describe the IVC?
It does not have any tunica media.
What are venous valves?
Valves in many veins that prevent a reversal of blood flow.
Where do you commonly see venous valves?
Lower limb e.g. great saphenous vein has 15 valves.
What do valves consist of?
Two posed cusps.
What veins don’t have valves?
- SVC.
- IVC.
- Veins of head and neck.
- Ophthalmic veins.
- Dural sinuses.
- Vertebral veins.
- Cardiac veins.
- Hepatic veins.
- Pelvic veins.
- Portal veins and its tributaries.