<span>Mollusca have one heart while Annelids have five heartsMollusca can have open circulatory system but Nematoda and Platyhelminthes have closed circulatory systemMollusks are marine creatures while Nematoda and Platyhelminthes are land creaturesMollusks have a more complex system then any other phyla<span>Mollusks have shells, either externally or internally, but phylum such as Cnidarians, Annelids, Nematoda and Platyhelminthes do not
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Muscle cells contract because of contractile proteins.
The likelihood of a cell firing is typically determined by adding both the excitatory and inhibitory synaptic input.
<h3>What is a cell?</h3>
A cell can be defined as the fundamental functional, structural and smallest unit of life, which is found within the body of an organism.
Generally, the likelihood of a cell firing is typically determined by adding both the excitatory and inhibitory synaptic input. Thus, the net sum of the excitatory and inhibitory synaptic input would determine whether or not a cell fires.
Read more on cells here: brainly.com/question/13846411
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A should be the answer correct me if i am weong!!! sorry