Question

The signal transduction of steroid hormone across cell is through

• A. binding of hormone to the cytoplasmic receptor and the complex binds to hormone response element on $DNA$ within promoter $DNA$
• B. binding of hormone to the transmembrane receptor which initiates the production of second messenger that activates enzymes which further activates transcription factors
• C. binding of hormone to the transmembrane receptor which diffuse inside the cell cytoplasm and then activates the enzyme necessary for the activation of transcription factors
• D. binding of hormone to the cytoplasmic receptor that initiates the production of second messenger which activates enzymes that further activates transcription factors

Answer 1

Answer: (A)

Steroid hormones, being hydrophobic molecules, diffuse freely into all cells and act within the cell. Steroid hormones enter the cytoplasm of a target cell and bind with specific receptor proteins (mobile). Hormone-receptor complex then diffuses into nucleus and activates specific genes to form a new protein. This protein carries out the specific response for a particular steroid hormone.