During the early stages of human reproduction and prenatal development, the developing organism progresses through several distinct anatomical stages. Five of these developmental stages are listed below in alphabetical order:

blastocyst, fetus, gastrula, morula, zygote

List these five stages in the correct chronological order in which they occur, starting with the earliest stage.

The sex chromosomes in the cells of a biological mother are $XX$. The sex chromosomes in the cells of a biological father are $XY$.

1. State the sex chromosomes present in the body cells of their male fetus.
2. State the total number of chromosomes found in a normal, healthy haploid gamete of a human.