Hormone X produces its effect in its target cells via the cAMP second messenger system. Which of the following will produce the greatest effect in the cell?
Hormone X produces its effect in its target cells via the cAMP second messenger system. Which of the following will produce the greatest effect in the cell?
The correct option is A Molecule of hormone X applied to the extracellular fluid surrounding the cell
A molecule of hormone X applied to the extracellular fluid surrounding the cell will have the greatest effect inside the cell. One molecule of hormone which uses cAMP as the secondary messenger is capable of producing 100s of cAMP molecule inside cells, so the greatest effect will be produced when the hormone is applied to the extracellular fluid outside the cell. Injecting the hormone inside the cell will have no effect as the machinery to produce cAMP is associated with the membrane. Injecting cAMP inside the cells may not be sufficient to bring on the desired changes.
Molecule of hormone X applied to the extracellular fluid surrounding the cell
A molecule of hormone X applied to the extracellular fluid surrounding the cell will have the greatest effect inside the cell. One molecule of hormone which uses cAMP as the secondary messenger is capable of producing 100s of cAMP molecule inside cells, so the greatest effect will be produced when the hormone is applied to the extracellular fluid outside the cell. Injecting the hormone inside the cell will have no effect as the machinery to produce cAMP is associated with the membrane. Injecting cAMP inside the cells may not be sufficient to bring on the desired changes.
