Cambridge O Level Biology · Syllabus 5090 · Coordination and Control
Adrenaline
What is Adrenaline?
A hormone secreted by the adrenal glands in situations such as fear or vigorous activity. It prepares the body for action by increasing the heart rate and increasing the blood glucose concentration, so that more glucose and more oxygen are delivered to the muscles for respiration.
This definition is part of the Coordination and Control chapter in Cambridge O Level Biology.
Questions students ask about Adrenaline
What does adrenaline do?
Adrenaline is secreted by the adrenal glands in demanding situations such as fear or vigorous activity. It increases the heart rate and increases the blood glucose concentration, so that more glucose and more oxygen are delivered to the muscles and they can respire faster. Adrenaline does not itself release energy; respiration does.