Question

Where does residual noradrenaline (that which hasn't been taken back up by the presynaptic neuron) remain?

a) Synaptic vesicles
b) Mitochondria
c) Extracellular space
d) Nucleus

Answer 1

The residual noradrenaline that hasn't been taken back up by the presynaptic neuron remains in the extracellular space.

Step-by-step explanation:

The residual noradrenaline that hasn't been taken back up by the presynaptic neuron remains in the extracellular space. When a vesicle fuses with the presynaptic membrane, neurotransmitter is released into the synaptic cleft, which is the extracellular space between the presynaptic and postsynaptic membranes. The neurotransmitter then diffuses across the synaptic cleft and binds to receptor proteins on the postsynaptic membrane.