Answer: Closed
Explanation:
At resting membrane potential( RMP) sodium channels remained shut, this is because , previously in depolarisation,the voltage gated sodium channels were opened for sodium to diffuse into the Axon. However these channels closed after reaching their refractory period,s.
Therefore a change in the extracellular concentration of sodium will not open them
Answer:
D. Ligase
Explanation:
Ligase is an enzyme that can catalyze the fusion of two large molecules through the formation of a new chemical bond, which is usually accompanied by the hydrolysis of a small end chemical group.
Ligases play an important role in linking DNA breaks during excision repair, DNA damage, or spontaneous lesions such as basal sites or oxidized bases.