Neuroanatomy Flashcards
The nervous system comprises the _________________ and _______________ nervous systems
Central
Peripheral
The brain and spinal cord make up the ________________ nervous system
Central
____________, _____________ and ____________ make up the brain stem of the brain
Midbrain
Pons
Medulla oblongata
Synapses are formed when _________
A neuron comes in contact with another neuron
The connection between a neuron and a muscle is termed a _______________
Neuromuscular junction
Nerves found in the central nervous system are called ____________
Tracts
Transmission of nerve impulses are multi-directional
True/False
False
Impulses travel only in one direction
A typical synapse is formed by the contact between the ____________ of a neuron and the ______________ of another
Dendrite
Axon terminal
In a situation where the terminal bouton of neuron A connects with the dendrite of neuron B, which is the presynaptic neuron?
Neuron A
Morphological
Ultrastructural
Functional
The above are _____________ of synapses
Classifications
____________ synapses are classified based on the neuronal components taking part in the synapse
Morphological
Axosomatic
Axodendritic
Dendritoaxonic
Dendriosomatic
The above are examples of ________________ classification of synapses
Morphological
What differentiates an Axoaxonic synapse from a serial synapse?
In Axoaxonic synapses , connection is made along the length of the other axon
In Serial synapses, both axons connect on the terminal bouton
_______________ classification of synapses are based on the neurotransmitters released by the synapse and their active sites
Ultrastructural
In the CNS, nerve fibres are called?
Tracts
In the PNS, nerve fibres are called?
Peripheral nerves
Nerve fibres comprise neurite processes, including?
- Axon
- Dendrites
What are peripheral nerves?
They are bundles of neurite processes
Nerves that transmit impulses to the sensory from the CNS is?
Afferent or motor neurones
Nerve fibres that return impulse from the sensory organs too the CNS are called?
Efferent or sensory neurones
Unmyelinated axons have a single covering called?
Schwann cell
A myelinated axon has?
Multiple myelin sheaths
The spaces between 2 myelin sheaths is called?
Nodes of ranvier
Transmission of impulse is faster in myelinated neurones. This is because of?
The presence of nodes of Ranvier, which speed up the transmission
A collection of nerve fibres in bundles are called?
Fascicles
There are 3 layers of covering for fascicles, namely?
- Endoneureum (inner most)
- Perineureum (middle)
- Epineureum (outer)
The membrane of an axon is called?
Axolemma
The membrane of a myelin sheath is called?
Neurilemma
Classification of nerves is by?
- By function
- By part innervated
- By velocity and Diameter of conduction
The destructive changes that take place when a nerve is cut is called
Nerve degeneration
The proliferative changes that take place after an injury for recovery is termed?
Nerve regeneration
How soon does nerve degeneration begin?
Hours after injury
When does nerve regeneration begin?
2 weeks after injury
Retrograde degeneration is degeneration in the ?
Proximal axon or Soma
Anterograde degeneration takes place in?
The distal Axon
When degeneration in one neuron transfers to another neuron, it is termed?
Transneuronal degeneration
Nissl bodies are composed of?
A collection of ribosomes
The disappearance of nissl substance is called?
Chromatolysis
The population of myelinated axons gives what colouration ?
White
The population of nissl bodies (soma) gives what colouration?
Grey colour
Factors necessary for regeneration?
- Absence of infection
- Separation or cut should be minimal and not total separation
Mention 2 clinical implications of regeneration in myelin sheaths
- Frey’s syndrome
- Neuroma
- Painful neurites
- Multiple sclerosis
A junction between 2 neurones is called?
A Synapse
The terminal end of an Axon is called?
Bouton or synaptic bag
The dense cytoplasm on either sides of the synapse is known as?
The Active zones
The space around the synaptic junction called ?
Synaptic cleft
