Neurons Flashcards
What factors limited the discovery of the neurone?
Its size and the requirement for very thin slices of brain tissue.
When was the neurone first described?
1740
In what year did the Golgi stain reveal neurones in the brain?
1873
In what year was the Golgi stain used to study circuitry of many brain issues?
1888
When was the term neurone coined?
1891
Who came up with Reticular Theory?
Golgi
What is Reticular Theory?
Nervous system was made up of a single continuous syncytium of neurones which communicate via continuity.
Who came up with the Neurone Doctrine theory?
Cajal
What is Neurone Doctrine Theory?
Nervous system was made up of individual neurones separated by small gaps which communicate via contact.
What is the function of the neurone?
The Neurones function is to receive, process and transmit electrical signals from one part of the nervous system to another.
What is the neuronal membrane?
A lipid bilayer membrane, consisting of different regions each with different proteins.
What proteins are located at the axon region?
Ion Channels
What proteins are located at the dendrites?
Receptor Proteins
What is the cytosol?
Suspends the organelles inside the cell in a protein matrix.
What is the soma?
Carries out cellular activities for the neurone. Contains:
A nucleus, ER and a golgi body (which stores intracellular calcium), mitochondria.
What is the Cytoskeleton?
Composed of a tubulin microtubule, a neurofilament and an actin microfilament which are constantly breaking down to allow new connections to be made.
Describe the structure of the axon?
The axon hillock is the part of the axon that connects to the soma, and it is possible to have multiple axons per neurone called axon collaterals.
How are proteins transported along the axon?
There is no RER so proteins must be transported from the cell body by microtubule and motor proteins which walk proteins to where their needed on the axon (anterograde or retrograde).
What is the function of the axon?
Action potentials are propagated and move along the axon by jumping between the nodes of ranvier.
What is the axon terminal?
Links one neurone to another and is the site of synaptic transmission.
What are dendrites?
Make up a dendritic field which receives input from connecting neurones.
What is Convergence?
Multiple presynaptic neurones pass their electrical signals to a single postsynaptic neurone.
What is Divergence?
One presynaptic neurone passes its electrical signal to multiple postsynaptic neurone.
What are the features of a dorsal root ganglion cell?
Its axonal projection goes to a distant brain area to affect different brain areas.
What are the features of a retinal bipolar cell?
Its axonal projection stays in a local brain area to affect only nearby neurones.
What are the features of a pyramidal cell?
Pyramid-shaped spread of dendrites to provide a large area for receiving synaptic input
What are the features of a stellate cell?
Radial-shaped spread of dendrites to provide a large area for receiving synaptic input
What is a unipolar cell?
A cell with one process exiting the cell body to provide a small area for receiving synaptic input.
What is a bipolar cell?
A cell with two processes exiting the cell body to provide a small area for receiving synaptic input.
What is a multipolar cell?
A cell with many processes exiting the cell body to provide a large area for receiving synaptic input.
What is a sensory neurone?
Receives input from sensory receptors.
What is a motor neurone?
Connect muscles to neurones.
What is a relay neurone?
Connect a synapse to another neurone.
What are interneurons?
Normally inhibitory neurons that lie within the spinal cord.