What are the two main types of hormones?

• A. Steroid and Non-Steroid
• B. Steroid and Peptide
• C. Steroid and Amino Acid
• D. Steroid and Protein

Answer: (A)

The main distinction is based on chemical structure and how they act on target cells: steroid hormones and non-steroid hormones. Steroid hormones are fat-soluble, derived from cholesterol, and slide through cell membranes to bind receptors inside the cell, often altering gene transcription to produce effects. Non-steroid hormones are water-soluble and stay outside the cell, so they bind to receptors on the cell surface and trigger signaling cascades (like cAMP or calcium pathways) that lead to rapid responses. This broad non-steroid group includes peptides, proteins, and amino acid–derived hormones, so pairing steroids with only one subset (for example, peptides) would miss the wide range of non-steroid hormones. That’s why the two main types are steroid and non-steroid.