THE CELL
CELL COMMUNICATION
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
The receptor is on the surface of the cell for a nonpolar hormone.
|
|
|
The receptor is inside the cell for a polar hormone.
|
|
|
The receptor is on the surface of the cell for polar hormone.
|
|
|
There is no difference.
|
Detailed explanation-1: -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-2: -The effects of polar-hydrophilic hormones are short-lived and fast, while the effects of nonpolar-hydrophobic hormones are longer-lasting, but take a longer time to take effect.
Detailed explanation-3: -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.
Detailed explanation-4: -Molecules that are nonpolar, such as steroids, diffuse across the cell membrane and bind to internal receptors. In turn, the receptor-ligand complex moves to the nucleus and interacts with cellular DNA. This changes how a gene is expressed.