Answer:
The correct option is B) send chemical messages across small gaps between neurons.
Explanation:
Neurons are the cells that make up our nervous system. Although they are connected to each other, they do not maintain physical contact with each other. The nerve impulse travels through the neuron, and when it reaches its dendrites, it is transmitted to the next neuron through the synapse, which is produced through the exchange of chemical substances called neurotransmitters. Neurons communicate with each other through the small spaces (or small gaps) between them, in a process known as synaptic transmission (where synapses are the connections between neurons). This synapse requires neurotransmitters (for example dopamine or glutamate) for the transmission of the signal or message, which after being released will bind to specific receptors causing an ionic change by opening or closing a channel.
Only small, uncharged molecules (like 02 for example) can go in or out of the cell by simple diffusion.
Since glucose is a relatively large molecule and ions (like Na+, Cl-) have an electric charge, they are unable to diffuse into or out of the cell.
However, since ions, glucose and other big or charged molecules are necessary for the functioning of the cell, there are special means of transport for them.
Integrated into the cell wall there are membrane proteins which serve as canals for transporting specific molecules like ions, glucose, etc.
Coprolites:<span> are feces of organisms which becomes fossilized excrements. </span>