16/09/2020
BIO304 – Lecture 2
Understanding neuron shape and structure.
- We are going to think about historical observations. A researcher Ramon y Cajal,
the Neuron doctrine.
- Golgi- labelling neurons, advances in neuronal tracing.
1. Early Inreoads into Understanding the Nervous System
o We didn’t always know that neurons are cells
o The cell theory in 1838 was
 made possibly by technological advances in microscopy
 Based on combined observations by numerous scientists. Robert Hooke
was the first to coin the word cell
o Cell Theory
 All living organisms are composed of cells
 The cell is the basic unit of structure and organization in organisms
 All cells come from pre-existing cells. Living things are cellular
o Reticular Theory of the Nervous System ingot\red the cell theory (1861)
 A camp of researchers referred to the nervous system as a reticulum- a
nervous system is made up of a single contiguous network, not sperate
cell.s
 This shows that they wanted to show neural transmission. This
kind of violates cell theory.
 Camillo Golgi and von Gerlach were strong proponents of the reticular
theory
 Camillo Golgi (found the golgi apparatus) invented reazone near,
o “the black reaction’ aka Golgi Stain
o It randomly labels some neurons in the tissur but not all of
them.