A Muscle Contraction Is Triggered When an Action Potential Travels Along the Nerves to the Muscles. Muscle contraction begins when the nervous system generates a signal. The signal, an impulse called an action potential, travels through a type of nerve cell called a motor neuron.
        
             
        
        
        
I think you’ll be able to be able to breathe better
        
             
        
        
        
No. The answer is C, 1/4.
        
             
        
        
        
Answer: Food Web
Explanation:
A food chain is a linear network of links in a food web starting from producer organisms and ending at apex predator species, detritivores, or decomposer species. A food chain also shows how the organisms are related with each other by the food they eat.
        
                    
             
        
        
        
It is because they have hydrophilic phosphate groups that are attracted to water and hydrophobic fatty acid tails that avoid water. 
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