14. What is the structure of proteins?the sequence of amino acids21. How do concentration gradients, size of NT, charge, and temperature affect the rate of electronic signaling?bigger gradients = higher rate
bigger NT = lower rate
bigger charge = higher rate
higher temp = higher rate22. Why are rbcs natural osmometers?their membranes are very permeable to water, but not so much to salts23. What are distinct characteristics of only protein-mediated transport?- have a maximum capacity
- specific to one substance
- competition between them
- transport can be inhibited by other compounds24. What does primary active transport have to do with phosphorylation?Primary active transporters, such as the sodium-potassium ATPase (also called Na+-K+ pump), are activated when ATP is hydrolyzed. When the ATP is hydrolyzed, the protein pump in the membrane becomes phosphorylated by the phosphate group that is removed from the ATP molecule. This activation allows for the transport of solutes across the plasma membrane against concentration gradients25. What are the generic regions of specialization for a "typical" nerve cell?cell body - input zone
axon hillock - trigger zone
axon - conducting zone
axon terminals - output zonewhere are the anatomically distinct neuron types located in the body?psuedounipolar - sensory neurons
bipolar - photoreceptor cells
multipolar - motor neuron26. What physiological processes are in common for all neuron types?All pass electrical signals in the form of an action potential27. Do all cells that have a negative resting potential have the capacity to fire an action potential? Why or why not?nope, some cells like a gut cell have like -15 mv but still won't fire an action potential28. In what form is information encoded in the nervous system?electricityHow does changing the action potential shape change the information?the longer an Action potential, the slower/less rapid/slower rate that the neuron fires at, like your heartIf you were to block certain ionic conductances underlying the action potential with drugs, how would various scenarios alter the encoded information?it wouldn't fire, or it could disrupt the rate and it would fire more slowly29. What is absolute and relative refraction?absolute - action potential cannot fire again
relative - action potential can fire again, but must be stronger than normal, can fire during repolarizationwhat type of ion channel blockers (drug targets) would affect rates of action potential firing?cocaine, adderall, TTX, Botulism, nicotine, caffeine30. Why do we clinically want to measure ion channel physiology?can't know if neurotransmission is actually working, all of our thought is done like this, no diagnosis of disease, open heart surgery possible32. What are the classic principles of the action potential?- all-or-none
- threshold = .15(amplitude)
- axon hillock - site of excitatory and inhibitory inputs
- propagated at specific conduction velocities
-non-decrementing33. How are local currents distinct from action potentials? If the former are decrementing, what is their physiological function?- local currents - decrement (1/e), action potentials don't
- local currents causes an action potential by causing ion channel proteins to open34. Does the ALL-or-NONE principle contradict the theory of recruitment?nope, they are a summation of individual fibers, but still obey all-or-none35. Do all nerve cells have the same threshold and space constant? Why or why not?No they do not, because some are myelinated and some need to be bigger. Like the one that reaches down your thigh36. What is a myelinated axon? How does saltatory conduction velocity assist the nervous system in terms of energy, space, and speed?- Myelin is a fatty white substance that surrounds the axon of some nerve cells, forming an electrically insulating layer
- take up less space, and much faster because the current doesn't run through the myelin parts37. What is the physiological basis for Multiple Sclerosis? What other environmental factors could induce similar patient symptoms?- fibers fail to conduct at the proper conduction velocity, and myelin is degraded by their own immune system, axons become scarred
- lead/tin exposure, cleaning products38. Do Schwann cells or Oligodendrocytes assist in regeneration? Discuss?- Schwann cells
- they digest the damaged axons39. Compare and contrast electrical synapses with the traditional chemical synapse.- electrical - directly connect two cells, depolarizing, quick
- chemical - connect cells by a synaptic cleft, both depolarizing and hyper polarizing, and need an electrical signal to fire40. Why do scientists know so much about the NMJ and the ACh-R over that of all other synapses?- ACh-R - first structure of a protein in a lipid membrane to be studied
- were able to use a cobra and electric eel to discover the structure and map of ACh-R41. How do microtubules assist in synaptic transmission?- they shuttle down NT down the axon so it can be sent out to the synaptic cleft through exocytosis42. If you had a drug that blocked -ligand-gated ion channels -presynaptic uptake -phosphorylation -AChE -anterograde transport How would taking this "prescription" affect the excitability of your muscle?um, like nothing43. What are the properties of neuroglia?- do not branch or conduct impulses
- serves as connective tissue
- protects and nourishes brain44. What are the four classes of neuroglia?- astrocytes - establishes BBB, form scar tissue, uptake GABA
- oligodendrocytes - form myelin sheath cells
- ependymal - forms CSF
- microglia - engulfs foreign particles or other microgliaWhich class is protective again brain damage?ependymalWhich class is important during a stroke (and why?)astrocytes - they cannot keep up with excess glutamate and GABA, and then that causes neuronal deathWhich assists in immune responses?microgliaWhich assists to increase the conduction velocity of nerve impulses?oligodendrocytescerebral cortex- language centers
- "homunculus"basal nuclei- Parkinson'sThalamus- relay stationHypothalamus- thermostat
- endocrine systemsCerebellum + Hippocampus- Learning-memory
- Alzheimer'sBrain Stem- coma
- sleep centers
- reception/integration from spinal cord46. What are some common clinical causes of brain damage?-shaken or jarred by forceful impact
-neural tissue damage due to head injuries
-O2 deprivation
-Stroke47. What are the physiological mechanisms underlying a cerebrovascular accident and what are some new treatments to prevent further neuronal cell death?- rupture of brain vessels
- blockage of O2 and glucose
- neurons release L-Glutamate
- neurotoxicity
- massive neuronal death
- treatment - glutamate antagonists, anticoagulants48. What are some modern technical devices used to detect brain tumors and what are their principles of operation?- CAT - x-ray absorption
- MRI - vibration of protons, computer reconstruction
- PET - O2 emits positrons, gamma ray energy, & computer reconstruction49. What is plasticity and how is it related to use-dependent competition for cortical space?- remember small child with missing brain (mostly)50. What are some selective language disturbances that occur due to stroke or genetic defects?- Broca - can't find words
- Wernicke's - doesn't make sense52. What cell type does Parkinson's disease target? Be familiar with clinical symptoms, cellular causes and mechanisms, putative causes of this disease, and present as well as controversial treatments of the disease. How is this disease related to Schizophrenia?- dopaminergic neurons
- loss of basal nuclei
- muscle rigidity, involuntary tremors, memory impairment, facial motor cortex loss of control
- L. Dopa
- Selegiline
- fetal transplants
- deep brain stimulation53. What cell type does Alzheimer's disease target? Be familiar with clinical symptoms, cellular causes and mechanisms. How is this disease associated with a metal?- cholinergic fibers
- B - amyloid proteins
- confusion, disorientation, personality changes
- Too much Al messes it up, and they get caught in the tangles, calcium leakage can also cause it55. What is the reticular formation? How does it relate to your alertness? How can we measure alertness and what IS this electrical signal? What are the levels of consciousness? What is an electrocerebral silence?- part of the brain stem
- center of alertness
- by EEG, on the skull surface
- full alertness, wakefulness, sleep stages, coma
- no more waves can be measured, brain dead56. Describe why sleep is an active process. Distinguish between slow-wave and paradoxical sleep (delta and beta waves respectively).- consumes O2
- slow-wave - 30-45 minutes, nightmares, motor body movement
- paradoxical - REM, dreaming, deepest sleep, 10-15 minutes
