AP BIOLOGY

Detailed explanation-1: -Answer and Explanation: Lipid soluble cell signaling molecules bind to receptors that are in the cytoplasm while water-soluble cell signaling molecules bind to receptors at the cell surface membrane.

Detailed explanation-2: -Lipid-soluble hormones diffuse through the plasma membrane to enter the target cell and bind to a receptor protein. Water-soluble hormones bind to a receptor protein on the plasma membrane of the cell.

Detailed explanation-3: -Plasma Membrane Hormone Receptors. Amino acid derived hormones and polypeptide hormones are not lipid-derived (lipid-soluble) and therefore cannot diffuse through the plasma membrane of cells. Lipid insoluble hormones bind to receptors on the outer surface of the plasma membrane, via plasma membrane hormone receptors.

Detailed explanation-4: -Signaling molecules that bind to cell-surface receptors do not have to cross the plasma membrane; thus, they can be large or small, hydrophilic or hydrophobic. By contrast, signaling molecules that bind to intracellular receptors must be sufficiently small and hydrophobic to diffuse across the plasma membrane.

Detailed explanation-5: -Cell surface receptors (membrane receptors, transmembrane receptors) are receptors that are embedded in the plasma membrane of cells. They act in cell signaling by receiving (binding to) extracellular molecules.