Subsequent loss or inactivation of the remaining normal allele in a somatic cell, known as loss of heterozygosity causes cancer to develop.

TLS Online TPP Program

#Id: 1009

#Unit 5. Developmental Biology

Mammalian sex determination is governed by the gonad-forming genes and by the hormones elaborated by the gonads.

TLS Online TPP Program

#Id: 1010

#Unit 5. Developmental Biology

In mammals, the conversion of the genital ridge into the bipotential gonad requires, among others, the Sf1, Wt1, and Lhx9 genes.

TLS Online TPP Program

#Id: 1011

#Unit 5. Developmental Biology

In mammals, the bipotential gonad appears to be moved into the female pathway (ovary development) by the Foxl2, Wnt4, and Rspo1 genes.

TLS Online TPP Program

#Id: 1012

#Unit 5. Developmental Biology

In mammals, the bipotential gonad appears to be moved into the male pathway (testis development) by the Sry gene (on the Y chromosome), which triggers the activity of Sox9.

TLS Online TPP Program

#Id: 1013

#Unit 5. Developmental Biology

The testis makes two major hormones involved in sex determination-

-Anti-Müllerian hormone (AMH), causes the Müllerian duct to regress.

-Testosterone, causes differentiation of the Wolffian duct into the male internal genitalia.

TLS Online TPP Program

#Id: 1014

#Unit 5. Developmental Biology

A fruit fly’s sex is determined predominantly by the number of X chromosomes in each cell.