What are the series of events in the SA nodal cells that directly cause autorhythmic contraction of cardiac muscle cells

Adrought killed all the plants in an agricultural farmland. gradually, due to wind and some birds for. nearby areas, new plants started sprouting l. what stage of succession was taking place in the farmland? a) competition b) nudation c) ecesis d) reaction e) migration

An area has a few days of low humidity, warm air temperature, and high air pressure. what kind of weather is this area experiencing? o fog o snow storms o sun

Which statement describes the punctuated equilibrium theory?