For a rotating column of air connected to a storm cloud to be
considered a tornado, it must do
which of the following?
A. reach speeds of at least 300 kilometers per
hour
B. last for over 15 minutes
C. make contact with the ground
D. occur during the day

Hey me with this one❤☺❤ how do you say that a cell also has a life span and death like an organism? give one example.

Ras is a g-protein that is activated when a growth factor attaches to egfr. its activation results in the replacement of a gdp molecule with a gtp molecule, thus allowing a signal transduction pathway to be activated. considering the signal pathway illustrated on this page, what is one potential outcome of a mutation in the ras gene that leads to ras protein hyperactivity. be specific.

Aragonite shells of clams, snails, or scleractinian corals may be preserved unaltered in cenozoic deposits, but they are generally dissolved or recrystallized in older deposits. true or false