Bio fianl exam Flashcards
Briefly Describe the conflict between Ramon y Cajal and Golgi. What did each one contribute to the ‘Neuron Doctrine’
They differed in how neurons communicate. Both got a noble prize, cajal was right but couldn’t do much without Golgi’s finding. Lead to the neural doctrine:
1) Neural Units: Neurons are individual cells with specialized compartments
2) Synaptic Contact: Neurons are non-continuous and contact each other at Synapses
3) Dynamic Polarization: Neurons transmission tends to be unidirectional
Golgi: suggests brain is physically connected to a “reticular network” , how they communicate. Reticular theory. Golgi develops silver impregnation methods to label a small number of cells, now termed Golgi Stain.
Cajal: suggested that the neurons communicate by synapsis
Neurosynaptic theory
- What is optogenetics, and how does it let us ‘take control of the brain?
TrpA1-tempature sensitive channelTRPA1 (heat sensitive channel)+ Laser heat->Neural activation
Channel light sensitive Channel rhodopsin + blue light ->neural activation
Insert using virus lets us control individual cell
Why is Wilder Penfield considered the father of modern Neuroscience? What and where were the two homunculi that he discovered? Briefly describe his experiments.
Wilder Penfield: Worked in epileptic patients to develop map of the sensory and motor cortex. Somatic sensory map, homunculus. He discovered the primary somatosensory cortex (S1) and the second somatosensory cortex (S2).
. Discuss the Action Potentials below
A. Describe the primary contributions of Na+, K+, and Ca2+ in action potentials and neurotransmitter release. Which ion(s) are critical for the generation of an action potential? Which ion(s) are critical for neurotransmitter release?
Na+ critical for generation of A.P need enough
K+ helps get axon terminal
Enough
Sodium Action potential start at axon helix Jumps in and out nods. K+ venalates mylenated areas Sodium Na+ and phosphate K+
what is the rise and what is the drop?
of the diagram?
Sodium Na+ and phosphate K+
If action potentials are ‘all or none’ how do neurons convey the intensity of a stimulus?
The intensity level of stimulius has the same peak/action potential , it wont change if not the right amount , thus it wont have NO intensety whatsoever. Signold grom the dendrites will meet at the axon helix if the right amount it will be able to proceed with the signaling/action
Who was H.M.? What could he remember? What could he not remember? Which area of his brain was damaged? (9 pts)
Developed anterograde amnesia following surgery
H.M bike accident could remember the past and couldn’t make new memories able to do motor exercises. Damage to the hippocampus.
6A) Describe three mechanisms that clear neurotransmitters from the synaptic cleft? (
- Reuptake
- Diffusion
- Enzymatic destruction inside terminal cytosol or synaptic cleft
) Give an example of a drug or toxin that that acts disrupts neurotransmitter clearance from the synaptic cleft. What type of protein does this drug target? (3pts
Cocaine dopemine pleasure. Dopemine dosnt reamin in synaptic cleft by reuptake pumps is taken away, cocain binds to dopemine reptake pumps and and block ability to remove dopemine from the synaptic cleft, ovetime the post s.c begins to cut back on number of dopemine receptors.
Nicotine activates Acetylcholine receptors
- In one or two sentences describe how each character responds to the news of Stephen’s diagnosis with ALS. What does this tell us about their personalities?
Jamie (2pts): wants to find the cure for the disease
Melinda (Jamie’s wife)(2 pts): sad, cries and writes about Stephan’s disease and family effects
Stephen (2pts) is in denial, ignoring the disease countinueing
w/ life, fell in love and wants to get married and have a baby.
A. Neurotransmitter is synthesized at synapse
B. neurotransmitter
C. calcium channels
D. receptor
E. reuptake channels
Why is ALS called Charcot disease in France and Lou Gehrig’s disease in the US? (4 pts)
In France Charcot discovered and came up with article describing ALS.
In the US Lou Gehrig was this famous baseball player Yankee athlete who ended to die from ALS.
Who are Jack Kevorkian and Thomas Youk? (2 pts)
Jack Kevorkian: Pro euthanasia, assisted Thomas youk in clinical suicide, he went to prison after this.
Thomas Youk: patient with ALS was on 60 min. show wanted dr.s help/assistant “clinical suicide”
- A person is born lacking all rods and cones. They cannot consciously detect light, but they have light-entrained circadian rhythms, meaning their brain sets itself to wake up at sunrise. How can the eye be sensing light in the absence of rods and cones? Which area of the brain regulates these circadian rhythms? Which type of special light receptor is involved? (6 pts)
- Rods
- High sensitivity to light, specialized for night vision
- More photopigment, increased light capture
- Low temporal resolution, slow response
- More sensitive to scattered light
- What is salutatory conduction? (4pts) Label the ‘*’ and ‘#’ on the diagram below. (2pts)
is the propagation of action potentials along myelinated axons from one node of Ranvier to the next node, increasing the conduction velocity of action potentials without needing to increase the diameter of an axon.
Mylenated sheath and rods of Ranvier
