Abstract
The physiological functions of several organs depend on tubule networks bearing specialized structures for filtration (kidneys), gas exchange (lungs) or secretion (pancreas).
There is a fine balance between building enough tubules for optimal (or even adequate) function and the geometric constraints imposed by tubule packing density and organ size. As a result some of our organs come in pairs.
For example, most people are born with two kidneys, but some are born with one horseshoe kidney.
During development, the two metanephric kidneys move upwards from their position in the pelvis to their final position at the back of the abdomen. Interestingly, if both kidneys stay in the pelvis, they can be forced together and fuse to form a u-shaped or horseshoe kidney which cannot rise into their typical position in the abdomen due to the position of the inferior mesenteric artery above it.
The one horseshoe kidney stays in the pelvis and usually does not cause serious health problems. However, the atypical shape and lower pelvic location of horseshoe kidney can interfere with the normal functioning of neighbouring anatomic structures.
This suggests we typically have two kidneys due to the geometric constraints of one larger kidney during development and the increased risk associated with the atypical location of one kidney during life.
There is a fine balance between building enough tubules for optimal (or even adequate) function and the geometric constraints imposed by tubule packing density and organ size. As a result some of our organs come in pairs.
For example, most people are born with two kidneys, but some are born with one horseshoe kidney.
During development, the two metanephric kidneys move upwards from their position in the pelvis to their final position at the back of the abdomen. Interestingly, if both kidneys stay in the pelvis, they can be forced together and fuse to form a u-shaped or horseshoe kidney which cannot rise into their typical position in the abdomen due to the position of the inferior mesenteric artery above it.
The one horseshoe kidney stays in the pelvis and usually does not cause serious health problems. However, the atypical shape and lower pelvic location of horseshoe kidney can interfere with the normal functioning of neighbouring anatomic structures.
This suggests we typically have two kidneys due to the geometric constraints of one larger kidney during development and the increased risk associated with the atypical location of one kidney during life.
| Original language | English |
|---|---|
| Journal | New Scientist |
| Publication status | Unpublished - 3 May 2023 |