1.1 neuro - neurohistology Flashcards
How are neurons classified?
By their structure and function, including types such as pseudo-unipolar, bipolar, and multipolar.
What are the important characteristics of neurons?
Excitable (generate and propogate action potentials), postmitotic (do not divide), and highly variable.
What are the parts of a neuron that should be sketched and labeled?
Cell body (soma), nucleus, dendrites, axon, myeline sheath
What is the function of an axon?
To send information and carry nerve impulses to other neurons, muscle fibers, or glands.
What is the function of a dendrite?
Cellular extensions that receive information.
What are the 3 types of neurons in vertebrates?
- Pseudo-unipolar (1 process exits the soma and splits into a central -to CNS- and peripheral -to environment- process)
- Bipolar (1 axon and 1 dendrite)
- Multipolar (1 axon, many dendrites)
What are the components of a synapse?
- Presynaptic neuron
- Synaptic vesicles
- Presynaptic membrane
- Neurotransmitters
- Synaptic cleft
- Postsynaptic membrane
- Receptors
- Postsynaptic neuron
What is the primary function of neuroglia?
Support, nourish, and protect neurons. Form the blood-brain barrier
What is the difference between neurons and neuroglia?
Neurons are excitable and postmitotic, while neuroglia outnumber neurons, do not propagate impulses, and can divide.
What are the types of glia found in the central nervous system?
- Astrocytes
- Oligodendrocytes
- Microglia
- Ependymal cells
What are the types of glia found in the peripheral nervous system?
- Schwann cells
- Satellite cells
What cells are responsible for myelination in the CNS?
Oligodendrocytes.
What cells are responsible for myelination in the PNS?
Schwann cells.
Which cell type lines the ventricles?
Ependymal cells.
Which cells migrate into the CNS and are not derived from the neural crest or neural tube?
Microglia.
What cell types form the blood-brain barrier?
- Astrocytes
- Endothelial cells of capillaries
What is the main component of gray matter?
Neurons and their proximal dendrites.
What is the main component of white matter?
Myelinated axons.