Please continue the question. Or is that it?
Answer: stroke volume
Explanation:
Stroke volume is the amount of blood ejected during ventricular contraction or for each stroke of the heart.
Bacteria were first observed by the Dutch microscopist Antonie van Leeuwenhoek in 1676
<u>-TheUnknownScientist</u>
Ecosystem and pond,
not sure though but good luck !