Just Prior to the Onset of Gastrulation in an Embryo

question 61

Multiple Choice

Just prior to the onset of gastrulation in an embryo, the "organiser" cells are specified. If you were to experimentally block the specification of these cells, what would you expect the result to be in the developing embryo?

• A) There would be no effect on development.
• B) Gastrulation would not occur, and normal development would cease.
• C) The body axes would develop normally, but the embryo would not grow appendages.
• D) The embryo would not develop an intestine, but all other organs and tissues would develop normally.