[Campbell Biology P.720] Regarding fungal life cycles and evolutionary history, which statem... | Practice Question

Regarding fungal life cycles and evolutionary history, which statement is true?

  • A: Karyogamy always precedes plasmogamy in the sexual life cycle, leading directly to haploid spores.
  • B: The heterokaryotic stage is characterized by diploid cells with nuclei from two parents.
  • C: Molecular evidence suggests fungi and animals diverged from a common unicellular flagellated ancestor over a billion years ago.
  • D: All fungi reproduce exclusively through sexual cycles, producing genetically identical spores.

Explanation

The text states that fungi and animals diverged over a billion years ago from a common unicellular ancestor that had a flagellum. Plasmogamy cytoplasmic fusion precedes karyogamy nuclear fusion , and the heterokaryotic stage involves haploid nuclei from two parents. Many fungi also reproduce asexually, and sexual reproduction produces genetically diverse spores.