When a nerve is stimulated, the signal is sent from neuron to neuron throughout the nervous system. when the electrical signal that traveled down the axon of the neuron is released and transferred to a different nerve cell, the signal crossing the synapse is question 4 options: ?

The correct answer for the blank is -

Chemical signal.

Explanation:

Neuron is referred the basic unit of the nervous system that helps in the transmission of impulses throughout the body.

It is primarily composed of dendrites, cell body, axon, and axon terminal (nerve ending).

When electrical signal passes the axon and reaches terminals, certain chemical signals called neurotransmitters are released by the nerve endings into the synapse ( which is a space between two neurons). Thus, chemical signal is transferred to the next neuron, which is further converted to electrical signal. In this way, transmission of signals takes place throughout the body.

it has one origin of replication, but it proceeds in two directions - d)

an adaptation is a change or process by which an organism takes to be better suited for its environment. for example; migration is a behavioral adaptation, this is needed because birds are not built to last extremely cold climates. there are different adaptations because there are different species needing to adjust to different things, bears don't migrate; they hibernate.