Final answer:
1. Males have XY chromosomes and females have XX chromosomes. The Y chromosome in males triggers the development of male-specific traits, and females inactivate one X chromosome as a Barr body.
Step-by-step explanation:
In biological terms, males and females differ in the constitution of their sex chromosomes. The correct answer is: 1) Males have XY chromosomes and females have XX chromosomes. In human genetics, females inherit two X chromosomes (XX), one from each parent, resulting in a diploid cell that has a total of 46 chromosomes. Males inherit an X chromosome from their mother and a Y chromosome from their father, also totaling 46 chromosomes in their cells, but with the difference of the XY configuration. The Y chromosome is responsible for triggering the development of male-specific physical characteristics and biological functions during growth.
In the case of females, because they have two X chromosomes, one of them is inactivated in each cell and becomes a Barr body, ensuring equal expression of X-linked genes between both sexes. Chromosomal abnormalities, such as men having an extra X (XXY) or Y (XYY) chromosome or women having an extra X chromosome (XXX), can occur due to errors during the process of cell division known as meiosis.