Question

question 4 of 10
how do fraternal twins form?
a. eggs are fertilized in different menstrual cycles.
b. one egg from each ovary is fertilized.
c. a zygote splits into two zygotes.
d. two sperm reach an egg at the same time.

Explanation:

Fraternal twins form when two eggs (one from each ovary in some cases) are released during a single menstrual cycle and each is fertilized by a separate sperm. Option A is incorrect as fertilization occurs in the same cycle. Option C describes identical twins (monozygotic) where a single zygote splits. Option D is not how fraternal twins form as each egg is fertilized by one sperm.

Answer:

B. One egg from each ovary is fertilized.