<span>Collin often experiences a "runner's high" during his daily three-mile run. this is most likely produced by endorphins.
Endorphins are related to a group of hormones which are secreted within the brain and the nervous system, it is like morphine chemicals which are produced. It is mostly produced when you exercise a lot, run high or stress etc.</span>
B. The tick is a vector. Vectors are like vehicles that carry genetic material. The tick is carrying the genetic material of lyme disease to the animal.
