NSCI 200 - L1: Cellular Anatomy

nervous system

organizes and controls an individual’s appropriate reactions with the environment, takes in sensory information that comes in and allows us to respond to it, functions are dynamic/vast/wide-ranging

neurons, glial

What 2 kinds of cells does the nervous system comprise of?

neurons

specialized nervous system cells that process and transmit information through electrical and chemical signals

multipolar, pseudo-unipolar, bipolar

What are the 3 types that neurons can be?

multipolar neurons

numerous branches that come from the cell body, including dendrites and axons

pseudo-unipolar (unipolar) neurons

sensory neurons that sense touch + temperature + pain, goes into spinal cord to convey information, has a cell body and an individual axon that splits into 2 axons

bipolar neurons

only found in the retina and inner ear

Golgi stain

silver stain that penetrates into the neuron, only shows a small number but allows you to see cell body in all of its processes

Santiago Ramon y Cajal

“father of cellular molecular neuroscience,” made incredibly detailed neuron drawings, concluded that the nervous system was made up of separate distinct nerve cells

The Neuron Doctrine

neurons are anatomically individual cells and these cells make up the nervous system

synapse

the site for rapid communication between neurons

~86 billion

Approximately how many neurons does the human brain contain?

~86 billion

Approximately how many glial does the human brain contain?

95

For most neurons, over ___% of their cytoplasm is in their axons.

1

Axons can be up to ____m long.

70 billion

Approximately how many neurons does the cerebellum contain?

1 billion

Approximately how many neurons does the spinal cord contain?

no — structures do

Does genome size predict nervous system size or complexity?

25 nm

The neuron cell body is approximately ____ in diameter.