[Campbell Biology P.280] The text suggests that the basic mechanism of apoptosis evolved ear... | Practice Question

The text suggests that the basic mechanism of apoptosis evolved early in the evolution of eukaryotes. Which of the following observations supports this conclusion?

  • A: Apoptosis in mammals relies on proteins identical to those found in single-celled yeasts.
  • B: Apoptosis occurs in nematodes, mammals, multicellular fungi, and single-celled yeasts, indicating a conserved mechanism across diverse taxa.
  • C: The complexity of apoptotic signaling pathways in humans implies a recent evolutionary origin.
  • D: Apoptosis is essential for normal nervous system development only in vertebrates, not in simpler organisms.

Explanation

The text explicitly states: 'The similarities between apoptosis genes in nematodes and those in mammals, as well as the observation that apoptosis occurs in multicellular fungi and even in single-celled yeasts, indicate that the basic mechanism evolved early in the evolution of eukaryotes.' This directly supports option B.