Muscle twitching can be explained by the action of synapse. A. Cell signaling
B. temporal summation
C. spatial summation
D. all for nothing response

a

Explanation:

Neurons enter a stage of excitability to transmit neuronal signals and go through a process of potential generation of action. It may often reach its threshold and become hyperexcited when a neuron is excited.

b) the inside picture would look at a very high temperature in a very low ph

the answer is d p: cell, q: organ, r: organ system, s: tissue