HUMAN NUTRITION

Detailed explanation-1: -Testosterone and estrogen are lipid-soluble signal molecules that cross the plasma membrane by simple diffusion. If these molecules can enter all cells, why do only specific cells respond to their presence? Nontarget cells possess enzymes that immediately degrade the molecules as they enter the cell.

Detailed explanation-2: -All classes of steroid hormones, glucocorticoids, mineralocorticoids, and sex hormones, are derivatives of cholesterol. Synthesis occurs in the placenta and ovaries (estrogens and progestins), testes (testosterone), and adrenal cortex (cortisol, aldosterone, and androgens).