Gruenwald in 1940 and Grobstein
in 1953.
What does this experiment show?
>Sufficiency
>Lineage
>Induction
1.Nephrons come from mesenchyme;
Collecting ducts come from the ureteric
bud.
2. The mesenchyme is incompetent
without the ureteric bud or some other
exogenous tissue.
3. The exogenous tissue is needed
only 24 hours; it throws a switch. Such
as switch is called ‘induction’
4. The ureteric bud is incompetent with
out the mesenchyme, ie reciprocal
induction
5. This is why Boyden stopped renal
development by blocking the Wolffian
duct.