The hormone adrenaline interacts with proteins located on the surface of cell and does not cross the cell membrane. however, larger steroid molecules such as estron cross cell membranes and inter act with protiens located in the cell nucleus. why is a large steroid molecule able to cross the cell membrane when a smaller molecule such as adrena; ine

The layers of the cell membrane is made of lipid

Explanation:

The cell membrane is made of a double-lipid layer, so it permits large steroid molecules like Estron or cholesterol since they are non-polar and lipid-friendly, whereas it does not permit the hormone adrenaline because it is a polar and charged molecule and non-lipid friendly.

your answer is "the 1950's"