Here are three examples each of protein hormones and steroid hormones:
Protein Hormones
Protein hormones, also known as peptide hormones, are hormones made up of amino acids. They are generally water-soluble and bind to receptors on the cell surface, triggering intracellular signaling cascades.
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Insulin: Regulates blood glucose levels by facilitating glucose uptake into cells. It is produced by the beta cells of the pancreas.
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Growth Hormone (GH): Stimulates growth, cell reproduction, and cell regeneration. It is secreted by the pituitary gland.
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Prolactin: Stimulates milk production (lactation) in mammary glands. It is also secreted by the pituitary gland.
Steroid Hormones
Steroid hormones are derived from cholesterol. They are lipid-soluble and can pass through the cell membrane to bind to receptors inside the cell, influencing gene expression directly.
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Testosterone: The primary male sex hormone, responsible for the development of male reproductive tissues, secondary sexual characteristics (e.g., facial hair, deepened voice), and muscle mass. It is primarily produced in the testes.
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Estrogen (Estradiol): The primary female sex hormone, crucial for the development of female reproductive tissues, the menstrual cycle, and pregnancy. It is produced mainly in the ovaries.
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Cortisol: A glucocorticoid involved in the regulation of metabolism, immune response, and stress response. It is produced by the adrenal cortex.
