Timeline of sexual development (masculine)

Fetal Development
Main article: SRY signaling cascade
 * 1) The SRY gene on the Y chromosome acts binds to the TESCO promoter sequence on DNA, causing SOX9 to be produced, but shuts down 3 days later.
 * 2) SOX9 continues to promote at TESCO, which leads the transcription of more SOX9 and a protein called DMRT1.
 * 3) DMRT1 also upgregulates at TESCO, but in addition blocks the transcription of FOXL2, which is part of the female gene regulatory network.
 * 4) Gonadal cells differentiate into Leydig and Sertoli cells due to the action of SOX9. Additional hormones such as Anti-Mũllerian Hormone, Testosterone/DHT etc. are released, and the tissue organizes into the male testis.

Puberty Induction
Main article: Hypothalamic-pituitary-gonadal axis
 * 1) The HPG axis becomes active at the start of puberty when a cluster of GnRH-producing neurons finishes its slow migration to the hypothalamus.
 * 2) GnRH pulses released by these neurons stimulates the production of FSH and LH (gonadotropins) in the pituitary gland.
 * 3) FSH and LH stimulate the production of testosterone in the testes.
 * 4) Testosterone inhibits the production of FSH and LH in the pituitary gland, to prevent too much circulating testosterone.
 * 5) Masculinization occurs as testosterone binds to the androgen receptor in many different tissues.

Masculinization from the Androgen Receptor

 * Vocal fold tissue lengthens, and the larynx protrudes to cause an "adam's apple".
 * Sebum production increases in skin cells, causing acne.
 * Bone Morphogenic Protein is activated in osteoblasts, causing skeletal structure to masculinize.
 * Androgenic body hair goes from vellum hair to pigmented, thicker terminal hair as the hHa7 keratin gene is activated (facial hair growth).
 * Growth Hormone and IGF-1 are stimulated, causing the Epiphyseal plate to form later than in feminine development.
 * Enlargement of penis and scrotal sack.
 * Many other things