In vertebrates, in connection with land access, there was an evolutionary need to radically restructure the respiratory and circulatory systems. List which aromorphoses in the structure of the respiratory and circulatory systems allowed animals to improve the absorption and transport of oxygen during the transition to each subsequent class. List at least four aromorphoses.
1) Amphibians first formed lungs and a second circle of blood circulation appeared, but the lungs were poorly developed, and arterial and venous blood mixed in the ventricle, so the role of gas exchange through the integument was great.
2) Reptiles in the lungs had folds that increased the surface area of the lungs, and a septum appeared in the ventricle of the heart, partially reducing the mixing of arterial and venous blood. This made it possible to completely abandon gas exchange through the covers.
3) In birds, the lungs have a porous structure and air sacs, which allows to increase the efficiency of gas exchange in the lungs. In addition, in the birds, the ventricles of the heart and the circles of blood circulation are completely separated, which allowed them to activate metabolism in comparison with reptiles and switch to warm-bloodedness.
4) In mammals, compared with reptiles, due to the alveolar structure of the lungs, gas exchange efficiency has increased even more. Moreover, like in birds, in mammals blood circulation circles are completely divided, which also allowed the development of warm-bloodedness during evolution.