The Biology Project > Cell Biology > Cell Signaling > Problem Set

Cell Signaling Problem Set

Problem 6: Steroid Hormones

Estrogen and testosterone are steroid hormones, and are most likely to bind to:

A.	membrane ion channel
B.	enzyme linked membrane receptor
C.	G-protein linked membrane receptor
D.	cytoplasmic receptors

Tutorial

Membrane ion channels, enzyme linked membrane receptors, and G-protein linked receptors are integral membrane proteins that bind their ligand (signal) and then cause second messengers to be produced inside the cell.

Steroid hormones estrogen and testosterone are non-polar and can pass through the lipid bilayer without binding to a membrane receptor. Nonpolar steroid hormones bind to special receptors in the cell cytoplasm. These receptors are modified and migrate to the cell nucleus where they activate transcription.

The Biology Project > Cell Biology > Cell Signaling > Problem Set