6. Vascular Dev- Exam 2 Flashcards
vascular dev occurs by what 2 mechanisms
vasculogenesis
angiogenesis
vasculogenesis=
coalescence of angioblasts
-major vessels such as the dorsal aorta and cardinal veins
angiogenesis=
vessels sprout from existing vessels
-remainder of vascular system
The early embryonic vascular system is a complex network. Preferential flow is related to what?
the development of organs which leads to enlargement of some vessels while other vessels are obliterated
The enlargement of vessels is by way of fusion with smaller vessels and partly by what?
the enlargement of individual capillary bed
The major arterial conduits in the early embryo are what? this is a continuation of what that arises from what?
dorsal aortas
-simply in continuation of the endocardial tubes- arise from aortic sac (distal most part of the trunctus arteriosus)
because of the changing position of the developing heart tube and pericardium, the cranial portions of the dorsal aortas come to describe what? what does this establish?
describe an arc on both sides of the foregut, establishing the first pair of aortic arches
how many pairs of aortic arches are present at some point during development? which one is only transient?
six pairs
5th aortic arch is transient
which aortic arch never forms or forms incompletely and regresses
5th aortic arch
how are the arches numbered and what do they do as they develop?
1, 2, 3, 4, 6
some become modified and some regress
all aortic arches come off of what
aortic sac
3 mm embryo:
- first pair of arches is _____
- second pair is just ______
- All other arches develop from the region of the _____
- Distally, the dorsal aortas fuse to form a ______
large
forming
aortic sac
single vessel
4 mm embryo (day 27):
- aortic arch is largely ____. Part of it remains and becomes the ______
- Arch 2 is ______. Remnants become the _____
- Arch 3 is _____ and well ______
- Arch 4 and 6 are being formed as ___ and ____ sprouts
- Arch 6 already has a sprouting branch of the ______
disappeared / Maxillary artery regressing / Stapedial Artery large / developed ventral / dorsal primitive pulmonary artery
10 mm embryo (day 29):
- Arch 1 and 2 have _____
- Arches 3, 4, 6 are quite ______
- The _______ has been divided so that arch 6 is now continuous with the _______
- Start to lose _____
- The intersegmental arteries will be important in the formation of the ________
disappeared large trunctoaortic sac / pulmonary trunk symmetry subclavian arteries
14 mm Embryo:
- symmetrical pattern is largely ____
- Further division of the ___ and ____
- Arch 3 forms ____ and ____
- Arch 4 stays on each side but becomes different strucutres: Left=, Right=?
- The dorsal portion of the right arch 6 has _____ and the left arch 6 will become the ______
- gone
- aorta / pulmonary artery
- common carotid artery / first part internal carotid artery
- Left Arch 4= part of aortic arch btwn LCC and left subclavian. Right Arch 4= Proximal righ subclavian
- disappeared / ductus arteriosus
14 mm Embryo continued:
- Intersegmental arteries have migrates upward to become the _____
- Arch 6 (Pulmonary Arch) gives off branches that grow toward the developing lung buds. The dorsal portion of the right arch 6 has disappeared and the left arch 6 will become the ______
subclavian arteries
ductus arteriosus
17 mm Embryo:
- a portion of the vessel that was the right dorsal aorta _____
- proximal portion persists and becomes the ____
disappears
right subclavian artery
At Birth:
- the distal part of the left 6th arch (ductus arteriosus) normally obliterates and becomes the ____
- the adult _____ system is now established
ligamentum arteriosum
aortic arch
aortic sac becomes what?
ascending aorta
aortic arch
brachiocephalic artery
first arches becomes what?
maxillary artery (portion)
second arches becomes what?
stapedial artery (portion)
third arches becomes what?
carotid arteries
fourth arches becomes what? (right and left)
Right= proximal right subclavian artery Left= aortic arch segment btwn left carotid and left subclavian artery
fifth arches becomes what?
transient and never well-developed