How Nerves Work 1 Flashcards
What structures are part of the nervous system?
- The brain
- The spinal cord
- The peripheral nerves
What are the subdivisions of the nervous system?
- Somatic nervous system
- Autonomic nervous system
- Enteric nervous system
What are the parts of the brain?
- Meninges
- Gyrus and sulcus
- Cerebellum
- Cerebrum
- Diencephalon
- Brainstem
What is the cerebrum made up of?
- Frontal lobe
- Temporal lobe
- Parietal lobe
- Occipital lobe
What is the diencephalon made up of?
- Thalamus
- Hypothalamus
What is the brainstem mad up of?
- Midbrain
- Pons
- Medulla oblongata
How many spinal nerves are there at each level?
- 8 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral
- 1 coccygeal
- 31 in total plus 12 pairs of cranial nerves
What is a ganglion?
A set of cell bodies
Where are the cell bodies of sensory fibres?
Ganglion
Where are the cell bodies of motor fibres?
Ventral horn
What is inside the white matter?
Axons
What is inside the grey matter?
Cell bodies
What happens at the dorsal horn?
Afferent sensory fibres come in
What happens at the ventral horn?
Efferent motor fibres go out
What components make up a neuron?
- Cell body (soma)
- Dendrites
- Initial segment (axon hillock)
- Axon
- Axon (presynaptic terminals)
What do dendrites do?
Receive information
What does the axon hillock do?
Triggers the action potential
What does the axon do?
Sends the action potential
What happens at axons act presynaptic terminals?
Release transmitter
Describe afferent (sensory) neurones.
- Peripheral nervous system
- Detect things in the environment
Describe the interneurons.
- CNS
- Decide what to do about detections
Describe efferent (motor) neurones.
- Peripheral nervous system
- Send signals for resolution
What are glia?
Non-neuronal cells that maintain homeostasis
What are the 3 types of glia?
- Astrocytes
- Oliodendrocytes
- Microglia
What do astrocytes do?
- Maintain the external environment for the neurone
- Surround blood vessels and produce the blood brain barrier
What do ogliodendrocytes do?
Form myelin sheaths in the CNS
What do microglia do?
Phagocytic hoovers mopping up infection
