You are presented with the question "What travel throughout the body in the blood?" and the following answer choices: 
- testes
 - matter vibrating
 - zygotes
 - gametes
 - kinetic energy
 - chemical messengers
 - Veins and arteries.
 - electromagnetic energy

Now knowing that endocrine hormones travel throughout the body in the blood and hormones, produced by the endocrine system, act as chemical messengers targeting specific organs, choose the best answer.


 

      chemical messengers   