It is found it the blood vessels so it should be the circulatory system.
Circulatory system. Veins and arteries
it is an organ, it doesn't belong to any other organs in the body but it does belong to a system in the body the digestive system.
The bicep is in the muscular body system.
Respiratory System
The cardiovascular system.
nervous system
The immune system
reproductive system
the digestive system
skeletal system :)
Circulatory system
The male reproductive system.