Neuronal Communication Flashcards
What are Sensory receptors?
Specialised tissues in the body that detect changes in the environment
How do Sensory receptors work?
By converting energy - acting as transducers - from one form of energy to electrical energy, which relays a signal to another part of the body
What are Pacinian corpuscles?
Pressure sensors in the skin consisting of concentric rings surrounding a nerve ending
How do Pacinian corpuscles work?
Pressure causes the rings to apply pressure on the sensory nerve fibre
- Nerve fibre detects CHANGE in pressure, not constantly applied pressure
What do sensory neurons do?
Carry the action potential from sensory receptor to CNS
Describe the structure of the Sensory neurone?
Long Dendron and short Axon
What do Relay neurons do?
Connect sensory and motor neurons
Describe the structure of Relay neurones
Many short dendrites and a short axon
What do Motor neurones do?
Carry the action potential from the CNS to effectors (muscles, glands)
Where is the cell body in Motor neurones?
Cell body is within the CNS
Describe the Axon in a Motor neurone?
The Axon is long
What portion of neurones are myelinated?
1/3
What cells create the Myelin Sheath?
Schwann cells
Describe the structure of Schwann cells?
- Several layers of membrane
- Thin Cytoplasm
What are gaps in the Myelin sheath called?
The nodes of Ranvier
