NEET PG DENTAL EXAM

Detailed explanation-1: -Lipid insoluble hormones bind to receptors on the outer surface of the plasma membrane, via plasma membrane hormone receptors . Unlike steroid hormones, lipid insoluble hormones do not directly affect the target cell because they cannot enter the cell and act directly on DNA.

Detailed explanation-2: -Growth hormone, insulin, calcitriol, and secretin are examples of molecules that cannot pass the cell membrane.

Detailed explanation-3: -Non-steroid hormones are made of amino acids. They are not fat soluble, so they cannot diffuse across the plasma membrane of target cells. Instead, a non-steroid hormone binds to a receptor on the cell membrane (see Figure below). The binding of the hormone triggers an enzyme inside the cell membrane.

Detailed explanation-4: -Hydrophobic (fat soluble) hormones like the steroid hormones do not attach to surface receptors. They break off from their blood transport proteins and then pass right through the cell and nuclear membranes attaching to receptors near or on specific regions of DNA (genes).