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 7: Bacteria, Membranes, and Cell Signaling

by: Rachel Johnson

Week 7: Bacteria, Membranes, and Cell Signaling Bio 107

Marketplace > Washington State University > Biology > Bio 107 > Week 7 Bacteria Membranes and Cell Signaling
Rachel Johnson
GPA 4.0
William Davis

Almost Ready


These notes were just uploaded, and will be ready to view shortly.

Purchase these notes here, or revisit this page.

Either way, we'll remind you when they're ready :)

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

The end of the lecture on bacteria, the lecture on membranes, and the beginning of cell signaling
William Davis
Class Notes
25 ?




Popular in Biology

Popular in Biology

This 10 page Class Notes was uploaded by Rachel Johnson on Monday October 12, 2015. The Class Notes belongs to Bio 107 at Washington State University taught by William Davis in Summer 2015. Since its upload, it has received 23 views. For similar materials see Biology in Biology at Washington State University.


Reviews for Week 7: Bacteria, Membranes, and Cell Signaling


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: 10/12/15
Bacteria III Other Mechanisms of Genetic Transfer 339 Transduction Transfer of DNA from one cell to another by viruses Results in new genes being transferred to a recipient cell after viral infection 339 Transformation Uptake of DNA from the environment Demonstrated by the Griffith Experiment Antibiotic Resistance 339 R plasmids resistance plasmids Small plasmids transferred by conjugation Contain antibiotic resistance genes Presence in cell is similar to F factor Contribute to widespread resistance 339 How antibiotics work Kill bacteria by inhibiting disrupting Cell wall formation peptidoglycan synthesis Gene expression ribosomes and DNA polymerase Other targets Only affect bacteria not viruses or eukaryotic cells 339 Where antibiotics come from Fungi Fleming s discovery of penicillin Plaques demonstrated the antimicrobial nature Bacteria Chemically synthesized 339 Resistance mechanisms Mutations in genes can allow bacteria to Reduce drug uptake Remove drug from cell Protein binds to drug and pumps it out Alter amplify target Inactivate degrade drug Example penicillinase 339 Why Incorrect use of antibiotics Wrongful prescription of antibiotics Overuse of antibiotic cleaners Example hand sanitizer Misuse of antibiotics in animals Using them to enhance growth Membranes I Lipids 0 v Includes C H and O typically 0 v Found in many different types of biological structures Triacylglycerides Phospholipids Cholesterols and sterols Hydrocarbons 339 Made of only H and C 0 v Serve as energy storage molecules Allows energy storage in a very small space high energy density Isomers v Structural Differ in covalent arrangement bonds between the carbons are different 339 Cis trans Differ in spatial arrangement Cis the same molecules are on the same side of the carbon backbone Trans the same molecules are opposite sides of the carbon backbone Fats 339 Functions Storage Structure v Synthesized by dehydration reaction Between glycerol and fatty acids Forms triacylglycerol Triacylglycerol 339 Three fatty acids linked to glycerol via ester linkages Bond between a hydroxyl and carboxyl Saturated and Unsaturated Fats 339 Saturated with H No double bonds Solid at room temperature Highest energy density possible Found in animal products 339 Unsaturated with H One or more double bonds Causes bend in the chain Liquid at room temperature Found in plant products Trans Fats 339 Made in the process of hydrogenation Invented by the food industry to increase the shelf life of food 0 v Less reactive than naturally occurring fats 339 Increases level of bad cholesterol and decreases level of good cholesterol Membranes II Phospholipids 339 Contain Glycerol The backbone of the molecule Two fatty acids Phosphate group 339 Two different types of chemical regions Hydrophilic head Hydrophobic tail Lipid Bilayers 0 v Cell membrane structure is made of phospholipid bilayers 0 v Phospholipids line up with each other forms the bilayer Minimizes tail interaction with water and maximizes head interaction 0 v Fluid mosaic model Phospholipids can move within membrane as can the embedded proteins Lateral movement side to side movement very frequent 107 times per second Flip op moving from one face of the membrane to the other about once a month Flipase aids in the movement 0 v Factors affecting uidity Temperature Increase temperature increase uidity Decrease temperature decrease uidity Amount of unsaturated hydrocarbons Higher amounts increased uidity Lower amounts decreased uidity Achieved by changing membrane composition 0 v Cholesterol Reduces uidity at moderate temperatures Prevents solidification at low temperatures Membrane Permeability 339 Water Polar molecule 0 is more electronegativity than H Electronegativity affinity for electrons H has a partial positive charge and O has a partial negative charge Causes of solubility A high dielectric constant Ability of a solvent to keep opposite charges apart Forms a hydration shell around ions 0 v Easily cross membrane Hydrophobic molecules Small uncharged and nonpolar molecules 0 v Don t cross membrane easily need channels Hydrophilic molecules Large charged and polar molecules Membrane Transport 339 Passive transport Diffusion Random movement towards equilibrium Molecules will spread out Results from a net inbalance in concentration Substances move from high to low areas of concentration down their concentration gradient Only moves in one direction Facilitated diffusion Requires proteins but not energy 339 Active transport Solute moves up its gradient Used when an inbalance is needed ie neurons Requires proteins and energy input 339 Channel proteins Forms a corridor for solutes to pass through has some regulation Examples Aquaporins For facilitated diffusion of water Ion channels For facilitated diffusion of ions Na K Ca2 and Cl Can open or close in response to stimuli 0 v Carrier proteins Similar to a revolving door Alternate between shapes to move solutes Examples Glucose transporter For facilitated diffusion of sugar Sodium potassium pump For active transport Used for action potential in neurons Cell Signaling I Types of Differentiated Cells 0 v Muscle cells Used to generate force for movement pumping uids etc 0 v Neural cells Originate from a gt Used for commun1cation and Signaling Sing1e genome 339 Skin cells Used to separate the organism from the environment and to provide a selective barrier Mesenchynal Stem Cells MSCs O 39 Progenitor cells for many tissues Extracellular signals are needed 0 90 Decides What type of cell the MSCs turn into to Activates division to make identical copies or self renewal Stem Cells vs Differentiated Cells 0 9 Stem cells and differentiated cells Have the same genes Can send and receive signals 0 9 Stem cells Has potential to become anything can divide and differentiate O Differentiated cells 9 Can t divide further once differentiated Carries out a specific function until apoptosis Cell Signaling Overview 0 v Stage 1 signal receiving cell receives an external signal in the form of a molecule Signaling molecule binds to a receptor on the target cell surface 339 Stage 2 signal transduction A series of chemical changes Within the cell triggered by receptor binding 0 v Stage 3 cellular response Signal Transduction 339 Often a series of protein chemical transformations Kinase enzyme that adds a phosphate group to a protein Phosphatase enzyme that removes a phosphate group from a protein


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

Bentley McCaw University of Florida

"I was shooting for a perfect 4.0 GPA this semester. Having StudySoup as a study aid was critical to helping me achieve my goal...and I nailed it!"

Allison Fischer University of Alabama

"I signed up to be an Elite Notetaker with 2 of my sorority sisters this semester. We just posted our notes weekly and were each making over $600 per month. I LOVE StudySoup!"

Jim McGreen Ohio University

"Knowing I can count on the Elite Notetaker in my class allows me to focus on what the professor is saying instead of just scribbling notes the whole time and falling behind."


"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.