Nerous System (Lec 3) Flashcards
sensory neurons:
function example of disease
acquire info from environment, respond to physical features such as temp, light, chemicals, touch
disease: Syphilis
interneuron:
function example of disease
process info and pass to motorneurons
disease: Parkinson
motor neuron:
respond
disease: ALS
List and Explain Neuron Structure
Dendrites: receiver
Cell body: “factory”, organelles for protein creation, etc.
Axon: conducts action potential away from cell body
synapse/axon terminal (20 nm gap)
connection specificity: connects with some neurons but not others
info travels only in one direction
List and explain 3 types of glial cells
oligodendrocytes (myelin sheath )
scwhann cells
astrocytes: blood brain barrier, surrounds blood vessels in brain
Satellite cells
type of glial cell that line the exterior surface of neurons in the peripheral nervous system
glial cell diseas
multiple sclerosis, affects
astrocytes
star-shaped glial cel, many functions including supporting endothelial cels blood brain barrier
dendrites
long receivers of a neuron (could contain hundreds of thousands), summation of receptors firg
selective leak channel:
mechanically gated channels:
always open and allow only certain ion (K+) leak channel assists with creating negative potential (depolarization) along w/ sodium potassium pump
ion-gated channels:
open due to change in potential
chemically (ligand)-gated channel:
requires a specific chemical (ligand) to open the gate
mechanically gated channels:
conformational change caused by pressure etc.
synapse: what ion is involved in the release of neurotransmitters
Ca2+
what are excitatory signals? What are two examples of excitatory neurotransmitters?
Excitatory signals open Na= channels and increase potential (leading toward depolarization)
examples: acetylcholine, glutamate
what are inhibitory signals? What are two examples of excitatory neurotransmitters?
inhibitory signals open K+ or Cl - channels and decrease potential (leading toward hyper-polarization)
examples: GABA and glycine
What are the two types of post-synaptic receptors?
ionotropic receptor: ion channels, instantaneous change in membrane potential
metabotropic receptor: induced signal cascade that lead to changes in ion channels
(example: G Protein)
What was the importance of Broca’ patient?
Brocca’s Area: couldn’t speak but understood language, damaged the area of brain that is important for motor aspects of language
What was the importance of Wernicke’s patient?
Wernicke’s area: had difficulty concentrating auditory and visual information into a coherent conclusion
What was the importance of Penfield experiment?
Penfield: stimulating the brains of epilepsy patients led to triggering vivid and specific memories. Indicating memories can be activated by stimulation specific locations in the hippocampus.
What was the importance of HM experiment?
Removed part of temporal lobe (epilepsy). Short-term memory could no longer function after surgery, but long0term memory sustained. He could create long-term memories through repetition over time, Short-term and long-term memory are stored with different mechanism and in different locations.
Difference between explicit and implicit memory
Explicit: conscious recall, declarative memory
facts, events, people,
location: medial temporal lobe and hippocampus
Implicit: unconscious recall, once mastered, becomes unconscious
location: amygdala, cerebellum, reflex pathways
Explicit memories can move to implicit memories when mastered
Short-term memory to long-term memory require
repetition and the synthesis of new proteins
Aplysia experiment
1) Initial shocks to sensory organ (siphon) created an action potential and direct path to motor neuron, causing the gill to contract
2) Repeated short-term shocks led to the involvement of an interneuron that release seratonin that activates PKA, triggering another chemical pathway that enhances the release of glutamate causing a more vigorous response (contraction of gill).
3) Repeated shocks in the long-term led to continous release of seratonin, which activated CREB that enhanced gene expression. This led to a new synaptic connection. The long-term learnd behavior involved the creation of new proteins where the short-term learning did not.
What is G-Protein?
G Protein coupled receptor is a transmembrane receptor involved with secondary messaging. G protein coupled receptors have a an extracellular and intracellular domain. The extracellular domain binds with a ligand, that causes a conformational change that releases the intracellular domain of the G proetin. the alph subunit detaches from the beta and gamma sub units
