I think observation and measurable.
Since it is the hearts job to pump blood throughout the body of the organism, the circulatory system would fail and the entire organism would suffer if the heart cells stopped working properly.
Answer:
meee lol I need friends <3
Answer:
The major functions of the circulatory system is it delievers oxygen and nutrients to cells and takes away wastes.
Explanation:
Hope this helps! :)
Where are they? Would love to answer
