What is the significance of steroid hormones?

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Multiple Choice

What is the significance of steroid hormones?

Steroid hormones are lipid-soluble, so they diffuse directly through the cell membrane. Once inside, they bind to intracellular receptors (in the cytoplasm or nucleus). This receptor-hormone complex acts as a transcription factor, turning specific genes on or off and changing which proteins are made. That’s why their effects tend to be slower to start but longer-lasting, because they rely on changes in gene expression. The other ideas describe different hormone classes. Receptors on the cell surface and signaling cascades are typical of peptide or amine hormones that use second messengers like cAMP or calcium. Steroid hormones don’t usually need those second-messenger systems. Saying they can’t cross the membrane is incorrect because their lipid nature lets them pass the lipid bilayer easily.

Steroid hormones are lipid-soluble, so they diffuse directly through the cell membrane. Once inside, they bind to intracellular receptors (in the cytoplasm or nucleus). This receptor-hormone complex acts as a transcription factor, turning specific genes on or off and changing which proteins are made. That’s why their effects tend to be slower to start but longer-lasting, because they rely on changes in gene expression.

The other ideas describe different hormone classes. Receptors on the cell surface and signaling cascades are typical of peptide or amine hormones that use second messengers like cAMP or calcium. Steroid hormones don’t usually need those second-messenger systems. Saying they can’t cross the membrane is incorrect because their lipid nature lets them pass the lipid bilayer easily.

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