Passive transport vs active transport sounds like what it is. In passive transport, there is no energy needed to get the molecules across the cell membrane, whereas in active transport, energy is expended getting the molecules across the membrane. Basically in active transport the ATP in your cells gives one of it’s phosphates to the transport proteins in your cell membrane and it lets select molecules in. These molecules are moving through a concentration gradient during active transport(with the help of ATP), from an area of low concentration to an area of high concentration.
        
             
        
        
        
Answer:
Binding of   <u>ACh (acetylcholine)  </u>  to receptors (ligand-gated) on the sarcolemma at the neuromuscular junction is vital for depolarization of the muscle fiber.
Explanation:
It allows acetylcholine to be released into this synapse when an action potential hits a neuromuscular junction. Acetylcholine attaches to the nicotinic receptors localized on the post-synaptic membrane of the muscle fibre's motor end plate, a specialized region.
Hence , the answer is  <u>ACh (acetylcholine) .</u>
 
        
             
        
        
        
Reactions involving fire are typically characterized as combustion reactions in which a material is oxidized, producing carbon dioxide, water, and carbon monoxide in some incomplete combustion reactions.
        
                    
             
        
        
        
I think atleast one is Oxygen because it needs air to digest