Lecture Two Flashcards
Inhibitory and Excitatory post synaptic potential
IPSP - causes the cell to become hyper-polarised
EPSP - causes the cell to become depolarised.
Discuss what happens at the voltage gated Na and K channels.
- the channels open when a the threshold is reached
- when the action potential is triggered the voltage gated sodium channels open
- electrical and concentration force pulls the sodium in.
- then the potassium ion channels opens
- electrical and concentration force is pulling it out.
Therefore creating equilibrium
In regards to Neurotransmitters discuss what happens at the synapse.
- Transmitter is synthesised and stored in vesicles
- Action potential invades the presynaptic terminal
- Depolarisation of the presynaptic terminal causes the opening of the voltage gated calcium channels to open
EXOCYTOSIS CAUSES THE NEUROTRANSMITTER TO RELEASE INTO THE SYNAPTIC CLEFT - Neurotransmitters bind to the receptors in the post synaptic membrane. Their channels open or close and it either inhibits or excites the cell.
What is the electrical and concentration inside the cell that has voltage gated sodium and potassium ion channels
It is more negative inside and has more sodium outside the cell than in.
What are afferent and efferent neurons?
Afferent neurons are those that carry information towards the neural processing structure. (From body to brain)
Efferent neurons are those that carry information away from the central nerve system. (Brain to body)
What are two electrophysiological recording techniques?
- Intracellular recording; electrode is placed inside the cell and records changes in membrane potential. Can also detect graded synaptic potentials which trigger action potentials.
- Extracellular recording; electrode is placed near the nerve cell of interest to detect action potential activity.
What are neural systems?
Typically grouped together to form neural systems that serve a broad functional purposes.
What are sensory systems?
(Visual, auditory, mechanosensory and chemosensory) that acquire and process information from the environment.
What are motor systems?
Motor systems allow an animal to respond to sensory and stored information by activating effectors (muscles or glands).
Motor neurons that activate the skeletal muscles to generate body movement make up the somatic motor system.
Those that govern the cardiac muscles, smooth muscle of the gut and other organs and glands constitute to the Visceral/autonomic motor system.
Within a tract what do the glial cells do?
The oligodendrocytes envelope central axons. In the same way that Schwann cells wrap the peripheral nerves.
The wrapping gives rise to myelin.
What are the different types of ganglia in the peripheral nervous system.
Sensory ganglia - lie adjacent to either the spinal cord (where they’re referred to as dorsal root ganglia) or the brainstem (where they’re called cranial nerve ganglia)
What is the enteric division?
It’s made up of small ganglia scattered throughout the wall of the gut. The ganglia of the enteric division modulate processes specifically concerned with digestion.
What is the forebrain made up of?
Diencephalon and cerebral hemispheres.
What are the seven parts that make up the central nervous system?
Spinal cord, medulla, pons, midbrain, cerebellum, diencephalon and two cerebral hemispheres.
What else does the brainstem contain?
Cranial nerves. That either receive input from cranial sensory ganglia via their respective cranial sensory nerves or give rise to axons that form cranial motor nerves.
