Question

what hormone causes the heart to beat faster?
insulin
oxytocin
epinephrine
prolactin

Explanation:

• Insulin: Regulates blood - glucose levels, not heart rate.
• Oxytocin: Associated with social bonding and uterine contractions, not heart rate increase.
• Epinephrine (adrenaline): Released in stress or fight - or - flight situations. It acts on the heart's beta - 1 receptors, increasing heart rate (chronotropic effect) and contractility (inotropic effect).
• Prolactin: Involved in milk production, not heart rate regulation.

Answer:

epinephrine