what happens to the pharyngeal pouches, post-anal tail, and somites in a shark, a turtle, a cow and a human?
Answers
Answer:
In case of vertebrates, the pharyngeal pouches form during the embryonic development. In the neck region, the lateral ectodermal surface is formed by the pharyngeal clefts to separate the arches. These pouches and clefts lineup, which develop into gills in case of fish (Eg: fish). In turtles, the thymuses develop from the pharyngeal pouches. In cows and humans (mammals), these structures become part of the other structures that include the thymus glands, thyroid gland and parathyroid gland, facial bones and muscles, some of the bones of the ears.
In case of fishes, they contain the post anal tail in some stages of their life cycle, and it may be lost or reduced in the adult ones. In mammals like horses, cows and humans, it develops into coccyx.