Session 17 - Nervous Tissue Flashcards
What is the perikaryon of a neuron?
The cell body
What is the cell body of neuron called?
Perikaryon
What are Nissl-bodies?
Granulations created by accumulation of organelles
What is the axon hillock?
The part where the axon begins from the cell body. It is characterised by a lack of Nissl-bodies
What is the axolemma?
The cell membrane of a neuron
What are the 3 classifications of neurons?
- Multipolar
- Bipolar
- Pseudo-unipolar
What are multipolar neurons?
Neurons that have a single axon and multiple dendrites extending from the perikaryon
Give 2 examples of where multipolar neurons can be found?
- Spinal cord
- Sympathetic ganglion
What are bipolar neurons?
Neurons that have only two processes from the perikaryon, an axon and a dendrite
Give 3 examples of where bipolar neurons can be found?
- Vestibulococchlear ganglion
- Retina
- Olfactory mucosae
What are pseudo-unipolar neurons?
Neurons that have a single process extending from the perikaryon which then splits into an axon and a dendrite
Give examples of where pseudo-unipolar neurons are found?
- Spinal ganglion
- Most of the cranial ganglia
What is another name for motor neuron?
Efferent neuron
What is another name for sensory neuron?
Afferent neuron
What are the 3 types of synapses?
- Axodendritic
- Axosomatic
- Axoaxonic
Name the 5 types of neuroglia found in the CNS.
- Oligodendrocytes
- Fibrous Astrocytes
- Protoplasmic astrocytes
- Ependymal
- Microglia
Name the 2 types of neuroglia found in the PNS.
- Schwann cells
- Satellite cells
Where are Oligodendrocytes found?
The white matter of the CNS
What is the function of Oligodendrocytes?
They are responsible for the production of the myelin sheath of the CNS
Where are fibrous astrocytes found?
White matter
Where are protoplasmic astrocytes found?
Grey matter
What is the function of astrocytes?
- Give structural and metabolic support to neurons
- Participate in repair process in nervous tissue
- Participate in the formation of the blood-brain barrier
- Cover the bare areas of neurons
- Forms glia limitans
Where are Microglia found?
White and grey matter
What is the function of Microglia?
They are phagocytic cells
Where are Ependymal cells found?
- Canalis centralis of spinal cord
- Brain ventricles
What is the function of Ependymal cells?
They produce, circulate and absorb cerebrospinal fluid
What is the function of Schwann cells?
They produce the myelin sheath of the PNS
