A Sertoli cell (a kind of sustentacular cell) is a "nurse" cell of the testicles that is part of a seminiferous tubule and helps in the process of spermatogenesis; that is, the production of sperm.
It is activated by follicle-stimulating hormone (FSH) secreted by the adenohypophysis, and has FSH receptor on its membranes. It is specifically located in the convoluted seminiferous tubules (since this is the only place in the testes where the spermatozoa are produced). Development of Sertoli cells is directed by the testis-determining factor protein.
B.Grass, cause without grass there wouldn't be any field mouse and without field mouse there wouldn't be any corn snake and without any corn snake there wouldn't be any hawks Hope i Helped ^_^
Reactants are formed inside the plant, and products are taken in from the environment by the plant. Reactants are taken in from the environment by the plant, and products are formed inside the plant.