Which term is used to describe sex cells produced by gonads?

The term that describes sex cells produced by gonads is gametes. Gametes are specialized cells required for sexual reproduction; they carry genetic information necessary for the formation of a new organism. In humans, there are two types of gametes: sperm cells produced by male gonads (testes) and egg cells or ova produced by female gonads (ovaries).

The other terms listed have distinct meanings. Zygotes refer to the fertilized cell that results from the union of a sperm cell and an egg cell, and they are the earliest developmental stage of a new organism. Ovum specifically refers to the female gamete, while spermatozoa refer to the male gamete. Although ova and spermatozoa are both types of gametes, they represent only one aspect of the broader category that includes all sex cells produced by gonads. Therefore, gametes is the most inclusive and accurate term for these sex cells.