The endoplasmic reticulum is a series of folded which are used by the cell for the transport of materials through the cell. a)nuclei

b)membranes

c)molecules

d)atoms

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

after receiving a stimus, the sensory receptors send(s) signals to the appropriate area of the body.  

the must be sensory neurons.  

hope its .