Cells of the Nervous System Flashcards
What are the two types of cells found in the nervous system?
Neurons
Glial cells
What are the features of a neurone?
Excitable cell
Carries AP
What are the features of a glial cell?
Non-excitable supporting cell
Much more plentiful than neurons
Much smaller than neurons
Describe the typical structure of a neuron
Dendrites
Cell Body
Axons
Synaptic terminal
Are there multiple dendrites and one axon or multiple axons with one dendrite?
Multiple dendrites with one axon
What cell organelles does a neuron contain?
Lots of mitochondria
rER
Diffuse golgi apparatus
Do neurons have a high or low metabolic rate?
High
What is the cytoplasm in the cell body of a neuron called?
Perikaryon
What is the cytoplasm in the axon of a neuron called?
Axoplasm
What is meant by amitotic?
Not going to regenerate
Under what circumstances can neurons grow back?
If the cell body has not been damaged
What is the function of the myelin sheath?
To insulate axons
Increase AP conduction speed
What forms the myelin sheath in the PNS?
Schwann cells
What forms the myelin sheath in the CNS?
Oligodendrocytes
How do glial cells form the myelin sheath?
Their cell membranes wrap around the axon
Mesaxon i =s formed
Cytoplasm gets extruded leaving on the cell membrane
What is MS?
Autoimmune disease in which the bodies immune system attacks the myelin sheath
What is the cause of MS?
Idiopathic
What does an MRI scan show with MS?
Whitish plaques of demyelination
What is the prognosis for MS?
Variable
Which country has the highest incidence of MS?
Scotland
What are the 3 types of neurons?
Pseuounipolar
Multipolar
Bipolar
What type of neurons are typical neurons?
Multipolar
What type of neuron are all sensory neurons?
Pseudounipolar
Are bipolar neurons common or rare?
Rare
Where are bipolar neurons found?
Retina of the eye
What composes grey matter?
Cell bodies
What composes white matter?
Myelinated ac=xons
In the peripheral NS what do myelinated axons form?
Nerves
In the PNS what do cell bodies form?
Ganglia
What are the main parts of the brain?
Cerebrum
Cerebellum
Brainstem
Diencephalon
What composes the cerebrum?
2 cerebral hemispheres
What composes the cerebellum?
2 cerebellar hemispheres
What composes the brainstem?
Midbrain
Pons
Medulla
What composes the diencephalon?
Thalamus
Hypothalamus
Where is the stalk of the pituitary gland found?
Below the hypothalamus
What are the 3 layers of cells in the developing embryo?
Ectoderm
Mesoderm
Endoderm
Which layer of the embryo forms the neural tube?
Ectoderm
How is the does the ectoderm form the neural tube?
Thickening of the ectoderm occurs
Neural plate thickens and fold over (invaginates)
Tube has a cavity
What are the cells in the periphery of the neural tube called?
Neural crest cells
What does the cavity of the neural tube persist as in the adult brain?
Ventricles
What do the ventricles of the brain contain?
CSF
What are the ventricles of the brain?
Lateral ventricles Interventricular foramen 3rd ventricles Cerebral aqueduct 4th Ventricle
What connects the 3rd ventricle to the lateral ventricles?
Interventricular foramen
What connects the 4th ventricle to the 3rd ventricles?
Cerebral aqueduct
What are the 3 meninges of the brain?
Dura
Pia
Arachnoid matter
Where is CSF present in the meninges?
Subarachnoid space
Where is CSF produced?
Choroid plexus
What are the dural folds present in the brain?
Falx cerebri
Falx cerebelli
Tentorium cerebelli
What does the falx cerebri separate?
Separate the cerebral hemispheres
What does the falx cerebelli separate?
The 2 cerebellar hemispheres
Where does the tentorium cerebelli lie?
Between the cerebrum and cerebellum
