Hormones are chemical signals that stimulate specific target tissues. Their specificity is due to the presence of signal receiving ‘receptors’ only in the respective target tissues. Where are these receptors present in case of hormones of protein nature.
Plasma membrane
Hormones carry out their functions by Binding to their specific receptors present on the plasma membrane of their target cell in the target tissue/organ. These receptors are also proteins, which are embedded in the plasma membrane.