Neurons and Glia Flashcards
What is the cell theory?
the cell is the basic functional unit of all living things
What is the Neuron doctrine?
the idea that the cell theory also applies to neurons: Neurons are the basic functional units of the nervous system
Name 3 structures that neurons have in common with other cells
Mitochondria, cell nucleus and ribosomes
What technique allows for the observation of neuronal structure?
Golgi Stain
What is the reticular theory?
the idea that the neurites of neurons seemed to fuse in a neural net
what is histology?
the scientific study of cells and tissues
What is microscopy?
the field that uses microscope to see objects that are not visible to the naked eye
What is microtomy and tissue processing?
a laboratory technique used in studying extremely thin tissue sections
What do neurons communicate with?
electrical impulses called action potentials (nerve impulses)
What is the soma of neurons?
The cell body; contains nucleus and organelles, DNA
What are the dendrites?
Receptors for neurotransmitters
What is the axon?
joins cell body to axon terminals
What is the axon hillock?
point of contact between the soma and the beginning of the axon
What are the axon terminals?
contain packets of neurotransmitters (synaptic vesicles)
What is the synaptic cleft?
gap between neurons where neurotransmitters are released
What is the myelin sheath?
fatty tissue that insulates axons (produced by glia)
What are the nodes of Ranvier?
breaks in the myelin sheath
What is the neuronal membrane made of?
Phospholipid bilayer - channels embedded into it
What are the 3 strucutres of the cytoskeleton of the neurons?
○ Microtubules
○ Actin filaments
○ Intermediate filaments
Pathology of cytoskeleton may result in?
Pathologies such as Alzheimer’s
What is axoplasmic transport?
Microtubules act as railroad tracks for the transport of materials from one part of the neuronal cell to another
What are the 3 main types of neuron (regarding their function)
○ Sensory/afferent neurons (body-brain)
○ Motor/efferent neurons (brain-body)
○ Interneurons (mediators)
What are the 4 types of Glial cells?
- Astrocytes
- Microglial cells
- Olidodendrocytes
- Schwann cells
What do astrocytes do?
Help the migration of neurons from one part to the other
Support the neurons structurally
What do microglia do?
Help to clear debris
Cleaning out dying neurons (apoptotic cells) (ex; in strokes)
What does macroglia do?
- Myelin helps to insulate and speed conduction of action potentials
- CNS - oligodendrocytes (many axons)
- PNS - Schwann cells (single axon)
What are the 2 types of macroglial cells?
- Olidodendrocytes
* Schwann cells
What is demyelination?
(removing of the myelin sheath)
What causes demyelination?
Multiple sclerosis
What is anterograde transport?
Type of axoplasmic transport
Kinesin transports materials from the soma to the axon terminals
What is retrograde transport? What substance is responsible for it?
Type of axoplasmic transport
Dyenin transports materials from the axon terminals to the soma
