Neurons and glia Flashcards
List the parts of a cell
- cell soma
- axon hillock
- axon
- dendrite
- dendritic spines
- synapse
- terminal axonal boutons
What are the three types of neuronal connections?
- synapses with another neuron
- neuromuscular synapses
- neuroglandular synapses
What function does the Node of Ranvier serve?
- where an action potential is generated and jumps between cells
- because the myelin sheath is insulated and comprised mostly of fat it cannot propagate, therefore it needs to ‘jump’
What is the structural classification of sensory neurons (i.e. dorsal root ganglia)?
- (pseudo) unipolar neurons
What terminology for cells in the CNS is used, and what are they?
- nuclei: collection of neuronal cell bodies
- tracts: bundle of nerve fibres (axons/dendrites)
What terminology for cells in the CNS is used, and what are they?
- nuclei: collection of neuronal cell bodies
- tracts: bundle of nerve fibres (axons/dendrites)
What terminology is used for cell types in the PNS, and what are they?
- Ganglia: collection of neuronal cell bodies
- Nerves: bundle of nerve fibres (axons/dendrites)
Define neuroglia, and list those in the CNS and those in the PNS
- supporting cells of the nervous system
CNS: - oligodendrocytes
- microglia
- astrocytes
- ependymal
PNS: - Schwann cells
- Satellite cells
List the four types of glial cells and their neuroglia composition in both nervous systems
- Supporting cells (astrocytes and satellite cells)
- Phagocytic cells (microglia and macrophages)
- Cells of the ventricular system (ependymal cells)
- Myelin producing cells (oligodendrocytes and Schwann cells)
What are the functions of astrocytes?
- structural support
- regulate ion concentration
- remove excess neurotransmitters
- from blood-brain barrier
- participate int he synapse
What is the function of the blood brain barrier?
- responsible for maintaining homeostasis of the microenvironment in the CNS
What are microglia, and what are their functions?
- immune cells in the brain
- microglia are the main phagocytic cells (development and injury) and antigen-presenting cells
- different lineage to other glial cells
What are ependymal cells, and what do they do?
- line fluid-filled cavities in the CNS (ventricles)
- cover the choroid plexus
What are oligodendrocytes, and what do they do?
- myelinates CNS axons
- one cell myelinates numerous axons
- increase speed of numerous axons
- prevents escape of electrical energy
- impulses jump from one node of Ranvier to the next
- do not envelop unmyelinated CNS axons
What are Schwann cells, and what is their function?
- increases speed of nerve conduction
- prevents escape of electrical energy
- impulses jump from one node of Ranvier to the next
- a Schwann cell can only myelinate one axon
