The first step in designing an experiment is the form a testable question.
Doctors inject medicines in veins because veins are more accessible and donot have high pressure due to which there is no risk of blood backing up with into the infused fluid.
However there are some cases when medicine is injected in artery but a lot of precautions needs to be taken while doing so.
<span>The wings on
the beetles are examples of vestigiality. Vestigiality is a structure with
attributes that have apparently loss its ancestral function but stil present
during evolution. It is a normal evolutionary process in the changing
environment that does not pressure them to evolve.</span>