A cofactor<span> is a non-protein chemical compound or metallic ion that is required for a protein's </span>biological<span> activity to happen. These proteins are commonly enzymes, and </span>cofactors can<span> be considered "helper molecules" that assist in biochemical transformations.</span>
        
                    
             
        
        
        
First blank I think is similar or the same and the second one is repell
        
             
        
        
        
-All signal transduction cascades are shut down immediately so as to prevent the cell from mounting a response.
-Cells are unable to respond quickly to hormones, and therefore signal transduction cascades always occur over a long time.
-Cells have to be able to function alone, because they are unable to work together in a coordinated fashion.
-Cells often have to respond very quickly to changes in their internal and external environments.
 
        
             
        
        
        
According to the bell magendie law, " the ventral spinal roots transmit motor impulses and the posterior roots sensory impulses,which establish a major landmark in the history of neuroscience."
The nature and physiology of the phenomena were described independently by sir charles bell , he is British anatomical scientist and french physiologist francois magendie after that Johannes peter muller confirmed it.
The ventral roots preganglionic sympathetic fibers of the atomic nervous system exit the spiral cord with ventral roots T1 through L2. It consist predominately of efferent somatic motor fibers. There are also 31 pairs of spinal nerves and roots. Eight pairs of cervical nerves exit the cervical cord at each vertebral level.
To learn more about the  Johannes peter muller here
brainly.com/question/16010930
#SPJ4
 
        
             
        
        
        
Answer:
Neurotransmitter
Explanation:
A neurotransmitter is a signal which transmits information between neurons at the end of the axon. This neurotransmitter can either be excitatory or inhibitory. Whenever an action potential is triggered within a neuron, the neurotransmitter releases this action potential into the synapses at the axon as either an excitatory or inhibitory signal before a new action potential is triggered.