New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here

week 4 tues notes

by: Mary-elizabeth Notetaker

week 4 tues notes bio 390

Mary-elizabeth Notetaker
U of L

Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

week 4 notes
Intro to Immunology.
Shira Rabin
Class Notes
Bio, bio390, immunology, introtoimmunology, UofL, rabin
25 ?




Popular in Intro to Immunology.

Popular in Biology

This 2 page Class Notes was uploaded by Mary-elizabeth Notetaker on Tuesday September 13, 2016. The Class Notes belongs to bio 390 at University of Louisville taught by Shira Rabin in Fall 2016. Since its upload, it has received 2 views. For similar materials see Intro to Immunology. in Biology at University of Louisville.


Reviews for week 4 tues notes


Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 09/13/16
Week 4, tues Tuesday, September 13, 2016 3:53 PM  Diffusion of ions thru membrane ○ Movementof charged particle- conductance ○ Ion channels:  Selective  Bidirectional- diffusion in direction of electrochem gradient ○ Superfamilies- large classes that evolvedfrom commonancestor  Studied w site directed mutagenesis- mutate part of gene encoding protein to change one or several AAs ○ Most channels gated- prevent mols from freely diffusing thru memb  Only open in certain circumstances  Regulated in 3 ways: □ Voltage gated- depend on charge on each side of memb  K+ channel- two helices, cytoplasmic N & C termini ◊ Tetramer-pore ◊ Bacterial K+ channel- short AA domain selects K only  P helix- selectivity filter  pH change- swing open at cytoplasmicend--> conformationalshift(polar things move) ◊ Euk K channel- 4 helix voltage sensing domain  Change membranepotential--> E force on S4--> mvmt of S4 relative to S5--> channel opens ◊ Open short time amt(milisec), close fast, stop ion mvmt automatically  Inactivation, mediated by cyto domain(4, one for each subunit)  Open pore-> want to plug it, plug removedlater to close channel  New voltage chain needed to reopen ◊ Channel can be open/close/inactive ◊ Each cell has many diff channels controlling diff processes-respondto diff voltage/change  Fascilitated diff- transporters help phyllic subs cross memb ◊ Passive, specific, regulated, saturable(at somepoint all transporters are busy) ◊ Solute binds on one side of memb->confo shift of transporter->soluteexposed to other side ◊ Ex) glucose transporter- causes confo shift, glucose phosphorylated when enters cytoplasm  Normally few glucose transporters in memb, low uptake as transporters saturated  Active transport- created/maintainsion/charge gradients(pumps) for K+, Na+, Ca+ and other ions ◊ Like facilitated diff…selective regulated and saturable ◊ Needs E bc goes against gradient ◊ Couples mvmtof subs against gradients to ATP hydrolysis ◊ Na+/K+ ATPase needs K+ outside, Na+ inside(3:2), pumps change  Electrogenic- contributes to charge separation  P type pump- phosphorylation causes confo change and ion affinity that allow transport against gradient  Only in animals- evolvedearly to regulate Volume, needed for life ◊ Other ion transport systems  Other p type pumps: H+ and Ca+ ATPases(ER)and H+/K+ ATPases(plants/stomach)  V type(vacuoler)use ATP but no phosphorylation ◊ Light E used: bacteriorhodospinuses light E to transport protons out of cell – Some archeabac – First memb protein crystallized  Light E activated retinal (euk photosnyth)  Pumps proton out of cell  Proton gradient used to make ATP(mitochondria)  Cotransport- coupling active to existing ion gradient- gradients created by active ion pumping store E that can be coupled to other transport processes ◊ NA+/glucose cotransporter  Keeps Na+ low in cells, comes back down gradient pulling glucose w it  Can transport 20k-fold against gradient  Glucose not phosphorylated- want to send out in blood  Leaves cell thru facilitated diff  Secondary transport- use E stored in ion gradient ◊ Plants use H+ not NA+  Coupled transport: – Symporters-move2 mols same way- one w gradient/one against  Many disorders in genes encoding protein ion channels- affect channels on nerve/musclecells ◊ Exception: CF… 1/2500 kids, recessive(few heteros in class)  Caused by defectiveCl channel- (CFTR)- pumps Cl- and HCO3- out of lungs, water flows by osmosis Bio 329 Page 1  Caused by defectiveCl channel- (CFTR)- pumps Cl- and HCO3- out of lungs, water flows by osmosis  Ligand gated(cAMP)CL ion channel, bicarbonate transport, activationreduced import of other ions, causes thick lung mucus  Over 1000 mutations □ Ligand gated- open when bound by ligand, not solute (neurotransmitters,cAMPon Ca+ channels) □ Mechano-gate-open in response to stretch/tension(haircells in ear)  Membpotentials and nerve impulses- membrane potential generated whenever charged separated, in all cell types ○ Neurons- use changing memb pots to transmit E  Dendrites- receive incoming info(short) □ Cell body: nus + met center Axon- long, outgoing info ○ Resting potential- memb potential of nerve/musclecell  Measure w microelectrodes  K+ gradients maintained by Na/K ATPase creating resting pot □ 3Na pumped out for every K in □ Outside more pos Action potential- cell stim, Na channels open, memb depolarization ○  Stim too weak- nothing  Stim over threshold, voltage gated Na channels open->actionpot  Quickly inactivated, K channel opens and goes down gradient, closed  Some ions on wrong memb side, but charge change is only imp thing □ Pumpedback by Na/K ATP-ase  Refractory period- cant do anything until charged up again  na pump needs to go from inactive to closed  "all or none"  Local, depolarize certain part of memb, areas near it on right sense it and activate, and so on(cascade to right only due to refrac period)  Signal propagates-> nerve impulse  Higher intensity->higher threshold neurons □ Not depolarizationalong same neuron- all or nothing □ Can be restim faster after refrac period ○ Thicker neurons send signals faster- resistance to flow dec as diameter inc  Limited approach, can jump btwn nodes to speed up 20x faster w myelin □ Myelin- sheaths neurons, lipid containing membsfrom schwann cells  Na cant pass along it, Na pumps at Nodes of Ranvier btwn schwann cells  Jumping synapse from end of nerve □ Neurotransmitters-premade chemicals storedin vesicles □ Steps:  Signal in terminal knob  Voltage gated Ca2+ channel opens  Synaptic vesicle fuse w memb ◊ Neurotransmitterreleased, diffuse across memb  Neurotrans binds receptor  Ligand gated channel in target cell open and depolarize(excite)or hyperpolarize(inhibit) ◊ Depends whether channels are for Na or K  Same neurotrans can have opp effect based on target  ACh activatesskeletal, deactivates cardiac  Norepinephrine stims cardiac and other muscles, contracts skin muscles  Glutamate stim brain cells and GABA inhibits brain  Transmitteraction terminated by reuptake or enzymatic breakdown(fastso signal brief on off) ◊ Many drugs block reuptake/degradationof inhibitors Bio 329 Page 2


Buy Material

Are you sure you want to buy this material for

25 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."

Amaris Trozzo George Washington University

"I made $350 in just two days after posting my first study guide."

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."


"Their 'Elite Notetakers' are making over $1,200/month in sales by creating high quality content that helps their classmates in a time of need."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.