Considering that, developmentally, the ureter grows from the bladder and joins the kidneys later on in development. How does the body manage to get the ureter to join when the two organs are so distant?

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Considering that, developmentally, the ureter grows from the bladder and joins the kidneys later on in development. How does the body manage to get the ureter to join when the two organs are so distant?

In: Biology

Is it possible that developmentally, the two organs could be connected by linking tissue that later forms the basis of a more substanial link?

The kindey forms from a structure called the mesonephric duct. This duct ends in a blind end just near the cloaca which at the early stages is just the front part of the very basic gut tube at the bottom. The cloaca will develop into the bladder as the embryo grows. The early kidney or mesonephric duct at this stage starts out very low in the embryo so the distance between the duct and the cloaca is very small. The top parts of the duct degenerate during development until the very bottom part is all that remains.

The kidney then moves up to its adult position, nestling under the adrenal glands. The adrenal glands dont grow out of the kidney, but are often pictured as if they are one object. Think of it more like a hat the kidney moves up into wearing. The ureter elongates as the kidneys move up. This makes the ureter long despite the fact that in development the distance between the “mesonephric duct” and the “cloaca” is very small. This explains it in greater detail.

https://web.duke.edu/anatomy/embryology/urogenital/kidneyAscent.jpg