Question

The nervous system does not use a terminal synapse to communicate with an effector. Instead,

a) chemical signals are released directly into the bloodstream
b) electrical signals travel across the synapse
c) neurotransmitters are released into the synapse
d) hormones are transported through the nervous system

Answer 1

In the nervous system, neurotransmitters are released at synapses to communicate rapidly with local neurons or muscles, while hormones are released into the bloodstream for broader, longer-lasting effects.

Step-by-step explanation:

The nervous system communicates with an effector not by using a terminal synapse but rather through different mechanisms depending on the type of signaling molecules involved. When the communication is with local neurons or muscles, neurotransmitters such as serotonin or norepinephrine are released at synapses. However, if the communication is system-wide, hormones released into the bloodstream carry the signal.

At a chemical synapse, neurotransmitter chemicals are released from the presynaptic cell into the synaptic cleft between cells. These chemicals travel across the cleft to bind to receptors on the postsynaptic cell, resulting in a rapid response that enables functions like movement and cognition. On the other hand, the endocrine system relies solely on chemical signaling, with hormones being released into the bloodstream and inducing responses in target cells throughout the body, which might take a longer time to manifest.