What is a male

Genetic basis

Gonadal basis

Structural basis

Genetic basis Egg contributes an X

23 chromosome pairs

Female is XX –both sex chromosomes same

Sperm gives a Y or an X

23 chromosome pairs

Male has X and Y

Sex of child determined by the “dad”

division

All body cells have 46 chromosomes

Sex cells ( sperm or egg) have only 23

During development of sex cells, division occurs (meiosis) only 23 chromosomes

Male vs. female

Autosomes same (22 ) pairs

Sex chromosomes not same

Major differences on the “Y” chromosome

SRY segment

SRY Responsible for testes

formation

Testosterone production

Sex characteristics

Sperm function

The Gonadal Basis

Gonads give a sexual identity

Males testes develop at week 7

Ovaries at week 12

Structural Basis Before 6 weeks embryo

has possibility to become either sex.

Mullerian ducts fallopian tubes/ uterus

Wolffian ducts sperm making ducts

Female is the default model Testes, if present

androgenic hormones and MIS ( mullerian inhibiting substance)

Also, 5 alpha reductase changes testosterone into DHT, another form of testosterone

T, MIS and DHT are responsible for making a male and female structure deterioration.

Receptors respond to these chemicals male organ and physiology

Female

In absence of T, MIS or DHT…………….a female Forms initially.

Y SRY sperm production Testosterone male ducts

MIS mullerian duct disintegrate proteins to regulate dna