- Nephrotome
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Nephrotome Latin nephrotomus Days 21 Precursor mesoderm Gives rise to pronephros Code TE E5.6.1.0.0.0.2 The nephrotome is a section of the mesoderm. It gives rise to the pronephros and eventually to the rest of the kidney.
A nephrotome is an obsolete term used to describe rounded mesodermal portions of the forming pronephros. In old texts the pronephros is described as forming through the fusion of multiple nephrotomes. Modern visualization methods such as scanning electron microscopy, in situ hybridization and confocal microscopy, combined with the simple approach of peeling off the epidermis to see the forming kidney, have shown that this is not the case. Nephric mesenchyme separates from the intermediate mesoderm as a single elongated primordia. As this primordia begins to undergo epithelialization the anterior portions of the pronephros form rounded protrusions, which then later become the dorsal branches of the pronephros that link to nephrostomes (distinct from nephrotomes). These rounded bumps are probably the structures observed in histological sections that are referred to as nephrotomes. Nephrostomes are thin ciliated funnels that link pronephric nephrons to the ceolom, and are not related to nephrotomes.
External links
Prenatal development/mammalian embryogenesis · Development of the urinary and reproductive organs (GA 11.1204, TE E5.6-7) Common urinary and
reproductive systemUrinary system
developmentNephrotome → Pronephros · Mesonephros (Mesonephric tubules)
WD → Ureteric bud + Metanephrogenic blastema
US → Urinary bladder + Urethra + Primary urethral groove + UrachusReproductive system
developmentPrimarily internalPrimarily externalLPM → Genital tubercle → Labioscrotal swelling → Scrotum or Labia majora
LPM → Genital tubercle → Primordial phallus → Penis or Clitoris
Peritoneum → Processus vaginalis or Canal of NuckHomologues Categories:- Embryology of urogenital system
- Kidney
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