Which type of hormones require the use of secondary messengers to exert their effects?

• A. Lipid-soluble hormones
• B. Steroid hormones
• C. Peptide hormones
• D. Thyroid hormones

Answer: (C)

Verified step by step guidance

1. Understand the nature of peptide hormones: Peptide hormones are composed of amino acids and are generally water-soluble, which means they cannot easily pass through the lipid bilayer of cell membranes.
2. Recognize the mechanism of action: Since peptide hormones cannot enter the cell directly, they bind to receptors on the cell surface. This binding initiates a cascade of events inside the cell.
3. Learn about secondary messengers: When a peptide hormone binds to its receptor, it activates an enzyme or a protein on the inside of the cell membrane, which then generates secondary messengers.
4. Explore common secondary messengers: Secondary messengers such as cyclic AMP (cAMP), calcium ions, and inositol triphosphate (IP3) are often involved in transmitting the signal from the receptor to the target molecules inside the cell.
5. Understand the effect: The secondary messengers amplify the signal and lead to a physiological response by activating or inhibiting specific pathways within the cell, ultimately exerting the hormone's effect.