Lecture 5 Flashcards
What are the three main types of neuron?
Unipolar
Bipolar
Multipolar
What are the 2 main features of unipolar cells?
They only have a single process stemming from the cell body and they are common in invertebrates
What type of neuron is a sensory neuron?
A pseudo unipolar neuron
Give an example of a bipolar cell
A retinal bipolar cell
Where are multi-polar cells most common?
In the CNS
Give an example of a multi-polar cell
Spinal motor neuron
Hippocampal pyramidal cell
Purkinje cell of the cerebellum
How many cells are there in the CNS?
10^12 - 10^14
What are Nissl bodies?
stacks of rough ER and prominent Golgi in neurons
What did Ramon y Cajal do?
1st to classify neuroanatomy properly
What did Camillo Golgi do?
Developed silver staining
In neurons how does the impulse flow?
Dendrites -> Cell Body -> Axon Hillock -> Axon -> NT release
Which glial cell myelinates in the CNS?
Oligodendendrocytes
Which glial cell myelinates in the peripheral nervous system?
Schwann cells
How many neurons can one oligodendrocyte myleinate?
10-40
How many neurons can one schwann cell myelinate?
1
What are astrocytes?
Glial cells which act as support cells
What are an astrocytes possible functions?
Glial filaments can provide support for CNS tissue
They can form connections between the neuron and capillary
They can supply nutrients and remove waster
The can ensure the environment around the neuron remains constant
What are microglia?
Resident phagocytes of the CNS, which are only activated when the brain is damaged
What are satellite cells?
Glia which encapsulate the dorsal root and cranial nerve ganglion cells and regulate their microenvironment
What are the principal functions of glial cells? (There are 8 in total)
Structural support Axonal insulation Removal of debris Buffering of K ions Removal of NTs Guide axonal migration during development Contribute to the blood brain barrier Nutritive function
Outline the process of neurulation
- Dorsal side thickens to form the neural plate
- The neural plate invaginates to form the neural groove
- The neural groove pinches off and becomes internalised to form the neural tube
What does the caudal neural tube become?
Spinal Cord
What does the rostral neural tube become?
Brain
What does the neural cavity become?
Ventriculuar system and central canal
What could an uncommitted neural crest cell possibly become?
Melanocyte Glial cell Sensory Sympathetic neuron Chromaffin Cell SIF cell Cholinergic Neuron Peptinergic neuron Serotinergic neuron
From the 3 vesicle foetus what does vesicle 1 become sin an adult human?
Cerbral cortex, basal ganglion, hippocampl amygdala and olfactory bulb
Thalamus, hypothalamus, subthalmus, epithalmus, retinae, optic nerve and tracts
From the 3 vesicle foetus what does vesicle 2 become in an adult human?
Midbrain
From the 3 vesicle foetus what does vesicle 3 become in an adult human?
Pons and Cerebellum and Medulla
