The mesoderm is one of the germ layers present in an embryo and it develops primarily into muscles and organs. The radioactive marker would therefore be visible in the adult organism's cardiac muscle cells, smooth muscle cells, skeletal muscle cells, red blood cells and many other such specialized cells.
Answer: anaphase
Explanation: Nondisjunction can occur during anaphase of mitosis, meiosis I, or meiosis II. During anaphase, sister chromatids (or homologous chromosomes for meiosis I), will separate and move to opposite poles of the cell, pulled by microtubules
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