Aortic arches in vertebrates

Aortic arches in vertebrates

1. Aortic Arches in vertebrates

2. In vertebrate major arterial channels include a ventral aorta and a dorsal aorta and usually 6 pairs of aortic arches . Blood leaves the heart through ventral aorta and through the external carotid arteries into head. Ventral aorta gives off 6 pairs of aortic arches running through the visceral arches. Each aortic arch having afferent branchial artery carrying venous blood to capillaries in a gill.

3. A dorsal efferent branchial arteries taking arteriole blood from the gill. All efferent branchial arteries of the same side dorsally join a lateral dorsal aorta which extend into head as the internal carotid artery. each lateral aortae units to form a single median dorsal aorta which continue into tail region as caudal artery. Branches from these main arteriole channels supply all parts of the vertebrate body

4. Fishes having 6 pair of aortic arches each passes through gill. Adults no is reduced to 4 or 5. In shark only 5 pairs (II, III, IV, V, VI) are functional. In teliost fish I, II are tend to disappears so 4 arches are functional. Fishes

5. Lives in water and remain the extarnal gill in addition lungs. 4 pairs of aortic arches (III to VI)are present. Same cases V arch is incomplete., reduces or absent. III arech is carotid arch, IV are systemic arch, V ductus caroticus , VI arch pulmocuteneaous atrey or arch supplying to blood to skin and lung. Amphibia

6. Reptiles Reptile are fully terrestrial in which gill are replaced by lung. 3 functional arches are present. Entire ventral aorta and conus split forming only 3 trunk- two aortic or systemic and one pulmonary. Right systemic arch (IV) leads to right ventricle carrying the deoxygenated blood or mixed blood. Ductus caroticus and ductus arteriosus are absent .

7. Warm blooded animal and ventricle completely divide so no mixing of oxygenated and deoxygenated blood. 6 arches are develop in the embryo but 3 arches are (III, IV, VI) present in adults. Ventral aorta is replaced by two independent aortae or trunks, systemic and pulmonary. Arch IV is single systemic aorta, right in birds and left in mammals, emarging from left ventricle and carring oxygenated blood. Birds and Mammals

8. Arch III with remain part of the other lost systemic arch is represented by a subclavian artery left side in birds and right side in mammals. Arch VI with remnants of lateral and ventral aortae represents carotid arteries, which arise from systemic aorta. Arch VI forms a single pulmonary trunk taking deoxygenated blood from right ventricle to the lungs.