Neuroscience: CHAPTER 2 Neurons and Glia

Neuron Doctrine

Neurons are separate cells

By Cajal, using the Golgi stain

Nissl Stain

Stains mainly free ribosomes, which are abundant in neuron cell bodies. Highlights cell bodies of neurons and glia.

Golgi Stain

This stain Helped identify that neurons are separate cells.

Fills about 1 in every 100-200 neurons

Camilo Golgi

(1843-1926)

Believes that ns is a web.

Santiago Ramón y Cajal

(1852-1934)

Believed that CNS made up of individual cells or neurons

Input Zone

Chemical input is transformed here to electrical signals—postsynaptic potentials

Conducting Zone

Axon conduct electrical signals—action potentials

Output Zone

Those electrical signals lead to chemical output—release of neurotransmitter

Sensory Neuron

Neurons that Sense stimuli in the environment

Interneurons & projection neurons

Neurons that Receive from and send to other neurons

Motor neurons

Neurons that Command body responses

Projection neurons

A type of interneuron

Has long axons and communicate between regions of CNS.

Pretty excitatory

Interneurons

Have short axons and communicate in one region of the CNS

Inhibitory

How many neurons are in the human brain?

86 BILLION NEURONS