49. The rate of heartbeat is accelerated by the hormone A.Adrenaline B.Acetylcholine C.Thyroxine D.Pituitrin
Answer: Option A Solution: The rate of heartbeat is accelerated by the hormone. The hormone adrenaline also called epinephrine is known as a stress hormone. In emotional upsets( like fear, anger etc.) this hormone is poured into the blood and it accelerates heart beat.
