Question

after a sperm enters the ovum, these two cells suddenly fuse, becoming one cell called a(n) ______
○ zygote
○ reproductive cell
○ gamete
○ phenotype

Explanation:

To solve this, we analyze each option:

• "zygote": When a sperm (male gamete) fuses with an ovum (female gamete), the resulting single cell is called a zygote.
• "reproductive cell": This is a general term for gametes (sperm or ovum), not the cell formed after their fusion.
• "gamete": Sperm and ovum are gametes; the fused cell is not a gamete.
• "phenotype": This refers to the observable traits of an organism, not a cell formed by fertilization.

So the correct term for the cell formed by the fusion of sperm and ovum is zygote.

Answer:

A. zygote