Which term describes the random joining of gametes to form a zygote?

• A. Independent assortment
• B. Crossing over
• C. Random fertilization
• D. Gametogenesis

Answer: (C)

The main idea here is how genetic variation arises when a sperm and egg meet to form a zygote. The term that describes the random joining of gametes is random fertilization. Because each gamete carries a different mix of alleles from the parents (thanks to crossing over and independent assortment during meiosis), any sperm could fertilize any egg, making the resulting zygote's genotype highly variable.

Crossing over creates new allele combinations within a single chromosome during gamete formation, but it describes events inside one gamete, not the fusion of gametes. Independent assortment explains how homologous chromosomes are distributed into gametes during meiosis, not the actual union of gametes. Gametogenesis is the overall process of making gametes, not the fertilization step itself.