For RNA polymerase II, the positioning factor is TFIID, which consists of TBP associated with up to 14 other subunits called TAFs (for TBP -associated factors). 

TLS Online TPP Program

#Id: 6572

#Unit 7. System Physiology – Animal

Human pancreatic polypeptide contains 36 amino acid residues and is produced by F cells in the islets

TLS Online TPP Program

#Id: 6573

#Unit 7. System Physiology – Animal

Pancreatic polypeptide is closely related to, 

polypeptide YY, a gastrointestinal peptide

neuropeptide Y, found in the brain & autonomic nervous system

TLS Online TPP Program

#Id: 6574

#Unit 7. System Physiology – Animal

In the normal male fetus,  the wolffian duct system on each side develops into the epididymis and vas deferens

TLS Online TPP Program

#Id: 6575

#Unit 7. System Physiology – Animal

The Y chromosome is necessary and sufficient for the production of testes, and the testis-determining gene product is called SRY (for sex-determining region of the Y chromosome)

TLS Online TPP Program

#Id: 6576

#Unit 7. System Physiology – Animal

SRY is a DNA-binding regulatory Protein, bends the DNA & acts as a transcription factor that initiates transcription of a cascade of genes necessary for testicular differentiation

TLS Online TPP Program

#Id: 6577

#Unit 7. System Physiology – Animal

When the embryo has functional testes, Leydig cells of the fetal testis secrete testosterone, and the Sertoli cells secrete MIS (MRF)