Hormonal action depends on whether the hormone is Lipid or water soluble. Lipid soluble hormones can cross the target cell membrane easily, get attached to the mobile receptors within the cytoplasm and reach the nucleus to perform their functions. However water soluble hormones are proteinaceous and these include insulin, oxytocin etc. These cannot cross the cell membrane easily. These get attached to the static receptors on the cell membrane. This attachment triggers the formation of secondary messengers that help these hormones to act on cells. Estrogen and Progesterone are steroid hormones that means these are lipid soluble hormones. Hence these attach to receptors within the cytoplasm.