400
Explain how an embryo is created during sexual reproduction (use specific vocabulary, including: gamete, sperm cell, egg cell, zygote, fertilization, cleavage, and embryo)
a male gamete (sperm cell) fertilizes a female gamete (egg cell) --> the joining of the sperm and egg produces a single-celled zygote --> cell division of the zygote occurs (cleavage) --> a multi-celled embryo develops.