Essentially, the 4th aortic arch and dorsal aorta form the aortic arch on the left, but since the right dorsal aorta regresses distal to the right 7th intersegmental artery, on the left they form the proximal portion of the subclavian artery.
22.
We don't have an article on " ventral aorta ", and a quick Google search reveals that, although fish have one ( and a dorsal aorta into the bargain ), mammals only have one aorta, which is divided into various sections.
23.
Essentially, the 4th aortic arch and dorsal aorta form the aortic arch on the left, but since the right dorsal aorta regresses distal to the right 7th intersegmental artery, on the left they form the proximal portion of the subclavian artery.
24.
Blood is conveyed to the wall of the sac by the vitelline arteries ( a branch of the dorsal aorta ), and after circulating through a wide-meshed capillary plexus, is returned by the vitelline veins to the tubular heart of the embryo.
25.
Insects also lack closed blood vessels; instead, they have a long, thin, perforated tube along the top of the body ( called the " dorsal aorta " ) that functions like a heart, and pumps haemolymph toward the head, thus driving the circulation of the internal fluids.
26.
The first chamber is the sinus venosus, which collects deoxygenated blood, from the body, through the dorsal aorta, into the rest of the body . ( In tetrapods, the ventral aorta has divided in two; one half forms the ascending aorta, while the other forms the pulmonary artery ).
27.
The ventral aorta delivers blood to the gills where it is oxygenated and flows, through the dorsal aorta, into the rest of the body . ( In tetrapods, the ventral aorta has divided in two; one half forms the ascending aorta, while the other forms the pulmonary artery ).
28.
The aortic arches start as five pairs of symmetrical arteries connecting the heart with the dorsal aorta, and then undergo a significant remodelling to form the final asymmetrical structure of the great arteries, with the 3rd pair of arteries contributing to the semilunar valves, possess smooth muscle of mesodermal origin.
29.
Each of these consists of a glomerulus, a tuft of capillaries which arises from lateral branches of dorsal aorta and drains into the inferior cardinal vein; a Bowman's capsule, a funnel like structure which surrounds the glomerulus; and a " mesonephric tubule ", a tube which connects the Bowman's capsule to the mesonephric duct.
