The chemicals used as neurotransmitters in humans are found in:
A) no other species.
B) other mammals also, but not in non-mammals.
C) other vertebrates, but not in invertebrates.
D) apparently all or nearly all other species.

Question

Quizplus · Accepted Answer

The chemicals used as neurotransmitters in humans are found in apparently all or nearly all other species, including invertebrates. However, the specific types and amounts of neurotransmitters vary between different species.

The Chemicals Used as Neurotransmitters in Humans Are Found In