ANATOMY
GENITO URINARY AND ADRENAL
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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by the 9th week
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by the 5th week
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by the 4th week
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by the 6th week
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Detailed explanation-1: -During early development, the kidneys lie close together in the sacral region of the embryo. However, as the abdomen enlarges, the kidneys are drawn apart and ascend to their final position in the lumbar region between weeks six to nine.
Detailed explanation-2: -The kidney’s ascent accompanies a change in the orientation of the renal hilum from a ventral orientation to a medial orientation, that is, a 90° rotation, but opinions differ regarding this movement.
Detailed explanation-3: -Prematurity effects on renal development As discussed above, new nephrons form at an exponential rate between 20 and 28 weeks of gestation. Nephron formation ceases between 28 and 36 weeks. Thus, in addition to low birth weight, premature infants born before 36 weeks may not have completed nephron development.