Question

Describe “The intracellular superfamily of hormones and how they mediate their effects”

Answer 1

Intracellular superfamily of hormones include steroid hormones and thyroid hormones because the target receptors of these hormones are located within the cell either in the cytoplasm or in the nucleus.

Steroid hormones enter the cell by the process of simple diffusion across the plasma membrane as steroid hormones are lipid. Thyroid hormones enter the cell by the process of facilitated diffusion. A series of events occur after binding of hormones with their receptors.

Receptor activation: binding of hormones induces conformational changes in the receptor and thus receptor becomes competent to bind DNA.

Binding with hormone response element: activated receptors bind with hormone response element which is short specific sequences of DNA located in promoters of hormone-responsive genes.

Alteration in transcription: Transcription if the gene to which receptor is bound becomes altered resulting into changed phenotypic expression.