The vertebrate forelimb initially develops in the embryo as a solid mass of tissue. As development progresses, the solid mass near the end of the forelimb is remodeled into individual digits. Which of the following best explains the role of apoptosis in remodeling of the forelimb?
A) Apoptosis replaces old cells with new ones that are less likely to contain mutations.
B) Apoptosis involves the regulated activation of proteins in specific cells of the developing forelimb that leads to the death of those cells.
C) Apoptosis involves the destruction of extra cells in the developing forelimb, which provides nutrients for phagocytic cells.
D) Apoptosis in the developing forelimb triggers the differentiation of cells whose fate was not already determined.
Ans: B) Apoptosis involves the regulated activation of proteins in specific cells of the developing forelimb that leads to the death of those cells.
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