Sex Chromosomes and Gender

Human cells contain 23 pairs of chromosomes for a total of 46. There are 22 pairs of autosomes and one pair of sex chromosomes. The sex chromosomes are the X chromosome and the Y chromosome. These chromosomes determine gender.

Grasshoppers, roaches, and other insects have a similar system for determining the sex of an individual. Adult males lack a Y sex chromosome and have only an X chromosome. Birds, insects like butterflies, and some species of fish have a different system for determining gender. In these animals it is the female gamete that determines the sex of an individual.

What about animals like most kinds of wasps, bees, and ants that have no sex chromosomes? How is gender determined? Read Chromosomes and Gender to find out!