Question

key
haploid (n)
diploid (2n)
refer to the life cycles illustrated in the figure above. which of the life cycles is (are) typical for animals?
i only
ii only
iii only
i and ii

Explanation:

In animals, the diploid (2n) organism undergoes meiosis to produce haploid (n) gametes. These gametes then fuse during fertilization to form a diploid zygote. Diagram I shows this pattern: diploid organism (2n) → meiosis → gametes (n) → fertilization → diploid zygote (2n) → mitosis to form diploid organism again. Diagram II shows an alternation of generations (a feature more common in plants where there is a multicellular haploid stage that can undergo mitosis). Diagram III has a haploid (n) organism undergoing mitosis which is not typical for animals.

Answer:

I only