[Solved] "If you're really concerned about the rights and dignity of women," Yigal asked his older brother,"how can you justify buying pornographic magazines?" Yigal's question indicates that he is in the ________ stage of development. A) formal operational B) conventional C) preconventional D) concrete operational Acetylcholine: A neurotransmitter involved in many functions including muscle movement and memory. Catecholamines: Organic compounds, including epinephrine (adrenaline), norepinephrine, and dopamine, that function as neurotransmitters and hormones in the body. Myelin Sheath: The fatty covering around nerve fibers that increases the speed and efficiency of electrical signal transmission in the nervous system. Neuron: A specialized cell transmitting nerve impulses; a nerve cell, consisting of a cell body, dendrites, and an axon.