The depolarization of the normally generates the action potential that leads to depolarization of all other cardiac muscle cells.

The depolarization of the ___SOMA NEURONAL normally generates the action potential that leads to the depolarization of all other cells of the heart muscle.

Explanation:

The depolarization of the neuronal body, that is, the body of the neuron, generates an action potential that is transported throughout the axon, until in the motor unit (union between neuron and muscle) the action potential is transmitted to the cardiac cell, depolarizing the membrane of the myocardial cell and thus effecting cardiac contraction.

Cardiac contraction occurs in a controlled, rhythmic and systematic manner, with autonomic character and as a consequence of the release of calcium from REL to LIC

organisms that lack symmetry are called asymmetrical and belong to phylum porifera/sponges.

organisms with specialized stinging cells belong to phylum cnidaria. stinging cells are called cnidoblast cells.

cnidarians show two morphological forms : polyp (sessile) and medusa (mobile)

filter feeding is observed in porifera members.  

alternation of generation is observed in coelenterata or cnidaria. there is alternation of asexual polyp form and sexual medusoid form. it is also referred as metagenesis.

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