Nervous Tissue Physiology Flashcards
The nervous system is divided into two parts. What are they?
Central and Peripheral
What does the CNS consist of?
Brain and Spinal Cord
What does the PNS consist of?
Everything outside of the CNS, eg. cranial nerves, spinal nerves, ganglia
What is the function of the CNS?
Control Centre
Integration
INTERPRETS sensory input
DDICTATES motor output
What is CNS interpretation based on?
Reflexes
Current conditions
Past experience
What are the two functional subdivisions of the PNS?
Sensory (Afferent)
Motor (Efferent)
Which neuroglia are in the CNS?
astrocytes
microglial cells
ependymal cells
oligodendrocytes
What are the neuroglia in the PNS?
satellite cells
Schwann cells
What is a neuron? What do they do?
A neuron is a nerve cell.
-structural units of the nervous system
-conduct messages from one part of the body to another through nerve impulses
What neurotransmitter do muscles use?
Acetylcholine
Role in brain functions eg. memory,
body functions eg. muscle contractio
At what voltage do voltage-gated channels open?
-55 mv
Explain summation?
Neuron can be stimulated into action potential by:
1) a single terminal stimulus numerous times over a short duration
2) multiple terminals all at onece
What is threshold?
Include voltage
When the value of the phosholipid bilayer reaches -55 mv
When this is reached, it triggers an action potential
At what voltage is resting state in action potential?
-70mv
In which period do the sodium-potassium pumps begin to work?
How many K+ and Na+ are transferred?
Refractory period
2 K+ are pumped into cell
3 Na+ are pumped out of cell
Cell eventually returns to resting state
