Which step precedes all of the other listed steps?
a) na+ rushes into the cell
b) ach is released by the motor neuron
c) an action potential starts on the sarcolemma
d) the sarcoplasmic reticulum is activated

answer: land bridge theory. land bridge theory held that shifting portions of dry land explained the finding of identical species on different continents. plate tectonic theory eventually eliminated the land bridge theory.

answer: if she breaths she a thho

explanation:

cellular respiration oxidizes food into energy in the form of atps.

glycolysis (6 c hexose) > 2x atps are used > 6c hexose biphosphate > 2 x 3c triphosphate >

2 x 3c pyruvate (2x nadh produced from nad) and (4x atp produced)

pyruvate actively pumped mitochondrial matrix.