Question

How does steroid hormone influence the cellular activities?

• A. Using aquaporin channels as second messenger
• B. Changing the permeability of the cell membrane
• C. Binding to DNA and forming a gene-hormone complex
• D. Activating cyclic AMP located on the cell membrane

Answer 1

The correct option is C Binding to DNA and forming a gene-hormone complex

Hormones bind to certain proteins called receptors, which are present on the cell membrane of the target cells or inside the target cells.

Binding of a hormone to its receptor results in the formation of a hormone-receptor complex.

The receptors that are present on the surface of the cell membrane are called membrane-bound receptors.

Hormone receptors which are present inside the target cells are called intracellular receptors.

Lipid soluble hormones, which include steroid hormones, can cross the cell membrane and enter the cell. They interact with intracellular receptors usually present inside the nucleus. This results in changes in the gene expression.

Fig: Mechanism of hormone action: Steroid hormone

On the otherhand, water-soluble hormones interact with membrane-bound receptors. To produce their effect, they generate second messengers (e.g., cyclic AMP, IP3, Ca++ etc.) inside the cell, which in turn regulates cellular metabolism.