Xylem tissue is important is the transport of water and minerals from the roots to the leaves of the plant. It is this water that is used in photosynthesis and also significant in the transpirational pull that significant in plant support. When the xylem is destroyed the plant wilts because it loses turgidity and dies because water is unable to reach the leaves for photosynthesis so the plant cannot make its food.
Answer:
Human blood contains a buffer of carbonic acid (H2CO3) and bicarbonate anion (HCO3-) in order to maintain blood pH between 7.35 and 7.45, as a value higher than 7.8 or lower than 6.8 can lead to death. In this buffer, hydronium and bicarbonate anion are in equilibrium with carbonic acid.
The both have a tail AKA A Spine in a embryonic
Basically they say "null hypothesis" according to source:
http://www.statisticshowto.com/what-does-it-mean-to-reject-the-null-hypothesis/