Amphibians have gills when they are young or they breathe through their skin. Adult amphibians either have lungs or continue to breathe through their skin.Amphibians have three ways of breathing. The first is with gills, seen on tadpoles and salamanders that do not leave the water. The second isâ¦.
Embryology is the branch of developmental biology that studies the beginning and early growth of sexually reproducing organisms. This life science specialty focuses primarily on embryogenesis (the formation and development of embryos). In humans, the term embryo is traditionally reserved for the first two months of development. After that point, the term âembryoâ is replaced by the term âfetus,â which then applies until birth. At the beginning of the individualâs development, the entity is a single cell. After two months, it has limbs, distinct fingers and toes, internal development, and countless cells.
A homologous structures are structures that share an evolutionary  ancestry. An example of homologous structures would be the bones in  the arms of a human, the wings of a b â¦ at, and the legs of a dog.hese structures may serve the same or different functions. For example, the wing of a bird and the arm of a human serve very different functions, but are considered homologous structures because of the evolutionary relationship between birds and humans.