UPSC CAPF AC 2020 Paper

In human body, the hormone which is secreted into blood and which controls the rate of heart beat is adrenaline. Adrenaline hormone is secreted by adrenal glands, located at tops of each kidney. This hormone is also called emergency hormone or fight or flight hormone as it is secreted in emergency or life threating conditions and increases the rate of heart beat and prepares body for appropriate response.