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Welcome to Physics 475 Understanding biology using “ simple ” ideas from physics.

Welcome to Physics 475 Understanding biology using “ simple ” ideas from physics. with an emphasis on single-molecule biophysics. You’ve (hopefully) made a good choice!. Your host: Professor Paul Selvin; Office: 365 Loomis Office Hr: after class and 10:30-11:30 am Tuesday.

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Welcome to Physics 475 Understanding biology using “ simple ” ideas from physics.

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  1. Welcome to Physics 475 Understanding biology using “simple” ideas from physics. with an emphasis on single-molecule biophysics You’ve (hopefully) made a good choice! Your host: Professor Paul Selvin; Office: 365 Loomis Office Hr: after class and 10:30-11:30 am Tuesday. (Can anyone NOT make it?) selvin@uiuc.edu: 244-3371 Your co-host: Marco Tjioe: Biophysics student (Taught this last year). Murat Baday: Biophysics student; graduates in May. tjioe2@gmail.com: 364 Loomis: 217-721-9047 mbaday2@illinois.edu: 328 Loomis: 720-722-2787 Office Hrs: Either Sunday 3-5 pm OR Tuesday 1-3pm. [Depending on whether HW due on Mon. or Wed.] HW due 1 week from date of assignment Course Info: M, W, 11:00 am-12:20 pm Rm 136 LLP go to my web site Or: http://physics.illinois.edu/courses/ then Physics 475

  2. Why are you here? 1. Study Biophysics --Physics to understand biology (Not biology to understand Physics.) --Most cool subject you will take in Physics. • Recently: Single Molecule Biophysics (Cool of the cool) Santa Barbara CA. vs. Urbana IL

  3. Why Single-Molecule? Santa Barbara (58˚F) Champaign (53˚F) Temperatures in 2007 (By ensemble measurements)

  4. Why Single-Molecule?Daily Temperatures in 2007 Fluctuation/heterogeneity matters! Invest in a warm winter coat & a swimming trunks in Champaign-Urbana!

  5. Why are you here? 2. Personal: You presumably could get 90% of information from reading You will do plenty…. Physical Biology of the Cell by Rob Phillips et al. Interaction with those who do biophysics …me, Murat, Marco… And with other students (do HW together)

  6. BioPhysics Two areas: Method Development New techniques to see better. Model Development What it means. We will study both.

  7. Should you be here? Yes, if you want to know about the physics of biology (medicine), single molecules. Prerequisites Physics 111, 112 (or equivalent) Some Statistical Mechanics, Elementary calculus • You will have to know: (Can learn) • Boltzmann’s Constant, kB • (relationship between energy and temperature) • Boltzmann Factor: exp(-Ei/kBT) • (proportional of being in some state with energy i, • given that it’s at temperature T) Remember in useful units: kBT = 4 pN-nm at Room Temperature; Usually small—Covalent bond 100kT But not in Biology! Hydrogen bond 3-5kT Common unit of energy: ATP~ 20-25 kBT ~80-100 pN-nm ATP is universal food (Can measure distance and get maximum force) • Gibb’s Free Energy, DG = DH-TDS; ≈ DE-TDS • DH ≈ DE : DS = Entropy = ln Wi , Wi = # of states • If DG negative, reaction will go there spontaneously (Fall downhill); • If DG is positive, takes some “push”. No previous biology assumed. I teach it in course.

  8. E1 E0 Temp, T Boltzman factor + Partition function(review of basic Stat. Mech. – see Kittel, Thermal Physic)s If T = 0 ºK, what proportion of particles will be in E1, Eo? Answer: Eo= 1E1 = 0 If T > 0 ºK, what proportion of particles will be in E1, Eo? J= represents jth state Z = partition function

  9. Simple case: Ball in gravitational field. Thermal fluctuations, finite probability of being at height, h. E = ?? Partition Function for 2-state system As ball gets smaller, probability gets smaller / larger ? “Ball” the size of O2? Why can you breathe standing up? What is 1/e height for O2? For O2, 1/e height is ~10 km ~height of Mt. Everest. (10 kM is “death zone”) Probability of dying if you go over 20,000 ft is 10% for every trip!!

  10. Required Reading • Physical Biology of the Cell, 2nd edition • by Rob Phillips et al. Publisher Garland Press. • (www.garland.shareddbook.com) • This is the first time I have used this book, so I’m uncertain about what parts I will cover. • “Definitely” Chapter 1-5. • There are several ways you can get a hold of the book. • Buy it from Amazon.com : $102. (“good” price”) • Rent it for 180 day from Amazon: ≈ $70. • Buy it chapter by chapter: $9/chapter • From VitalSource e-book version, which can be purchased or rented. • https://store.vitalsource.com/show/9781134111589 • Get book fast because 1st assignment is Chapter 1—assigned now! Due in 2 weeks. (There will be a quiz.) • There will also be readings assigned in class. • Need to know biology in order to do biophysics! • Using physics to understand biology! • Not biology to understand physics!

  11. Course Information Physics 475 Biological Physics Alternative title: Introduction to the physics of quantitative biology with an emphasis on single molecule biophysics Major concepts of physics inherent to biological systems.  Basics of biology, including protein and DNA structure and their organization into cells are discussed, with a  focus on single molecule biophysics.  Major techniques including optical and magnetic traps, and fluorescence microscopy, including "new" super-resolution techniques. Applications to cytoplasmic and nuclear molecular motors, bacterial motion, nerves, and vision. It’s only been last 10-20 years that single molecule measurements have been possible! Single: molecules, cells, species (men vs. women), planets… very hot, very cold, only if you look In singulo Biophysics

  12. Course Syllabus Physics 498Bio DNA, RNA, ATP & Proteins (Making, Folding) 1. Jan 14: Introduction to Biophysics: The Earth’s Temperature, King Kong and Bacteria 2. Jan 16: The Language of Life: DNA, Proteins, Carbohydrate, Lipids: How you eat! 3. Jan 21: No class (Martin Luther King Day)  4. Jan 23: Protein Folding in Silico—Computer Simulation (VMD)– Klaus Schulten 5. Jan 28, 30: Reg. Class  6. Feb 4: No class 7. Feb 6: Reg class Magnetic Tweezers, Atomic Force Microscopy About March 6: Mid-term Exam (Lec. 1-13) Imaging and Microscopy—Seeing small things: Fluorescence, Optical Traps Spring Break: March 18, 20 Diffusion Ion Channels and Vision Extraneous: Most Genes are few in Number—some surprising results Studying Gene Activity in Individual Cells Studying Gene Activity in Individual Cells II Student lectures (given over many nights) May 1st: Last class

  13. Grading (may be modified slightly if changes to course ) Grading 25%: written Homework : (about 9 total; drop lowest 1): (You CANNOT drop the last homework!) Work together, but turn in separately. Hand in at start of class– in class! (Do not be late.) 10% in-class Quizzes: (covering Phiilip’s or extra-reading) 25%: Written Project & Oral Project– Same topic -- 12.5% on written report: 10 pg report. -- 12.5% on oral report: 8-12 min plus 4 min for questions. 15% on midterm exam 15% on final exam 10% on classroom participation /class evaluation

  14. Plagiarism Not allowed! You will flunk the course. In written project… Something has always been written… (unless you have truly come up with something new.) Usually what’s written will be clearer than you can write it. But you want to independently understand it. And show me that you independently understand it. So… Read book/article, then close it, Then write your own version. This way you know you understand it, and can explain it in your own words. Also, when you “steal” a picture from somewhere, write in your paper where you got it from. A picture is worth a thousand words, but give credit where due.

  15. Yes, you get to evaluate class!Three (or 4) questions: 1. What was the most interesting thing you learned in class today? 2. What are you confused about? 3. Related to today’s subject, what would you like to know more about? 4. Any helpful comments. Answer, and turn in at the end of class. (I’ll give you ~5 minutes.) I’ll typically start class with some of your questions.

  16. Get to know each other With someone you don’t know, Find out their: • Name, Year, undergrad vs. grad. • Why you’re taking the course. • Tell one thing that’s surprising. Take 4 minutes (2 min/person) A few people will have to report!

  17. Mass? (density is the same): 10 x 10 x 10 = 103 Strength? a Cross-sectional area (rope): 10 x 10 = 102. 1/10… 1/dimension Strength/Mass ratio? King Kong is proportionally speaking is 10x weaker than regular gorilla! Regular gorilla with 10 gorilla’s on him—couldn’t walk.

  18. In water– held up by buoyant force. Bones do not need to support weight If have to, have super big bones– would sink. If whale stranded on the beach? Bones break; also overheat (because warm-blooded and water is going at conducting away heat, whereas air is not.)

  19. Big Ideas…the most amazing story ever… How old are the atoms in you? Where did they come from? Physics says your atoms are billions of years old! 13.7 Billion years ago, Big Bang. Our Universe Wikipedia • Dark Energy: permeates all of space: • Necessary for expansion of the universe at accelerating rate. • Dark matter –unknown what it is. • Look at large scale gravity affect on visible matter, need this. • Baryonic “heavy” (atomic) matter • Protons and neutrons.--visible

  20. Formation of atoms In Big Bang, Hydrogen was formed; within 3-20 minutes, during the rapid “expansion” of the universe, the smallest elements formed (by fusion because of super hot temp.), H, He, Li (and some radioactive Beryllium): Big Bang Nucleosynthesis. Within 100-200 million years, density fluctuations caused the first stars formed. (Also [I think] dark matter appeared to form) (Based on NASA's Wilkinson Microwave Anisotropy Probe (WMAP) released in February 2003—Nobel Prize, 2006) Cosmic Microwave Background—nearly constant background, formed about 400,000 years after BB. Universe expanded and been cooling ever since. Now about 2.73 ˚K.

  21. Formation of atoms up till Iron In Sun, form He. In more massive stars, form Carbon up to Oxygen. Therefore we are derived from a long-dead star which exploded and reformed to make us (& sun, earth…) Big stars: Elements up to Iron formed. (≈ 1 billion years passed and galaxies proliferated. CMB ≈19˚K, a billion years after the BB) (Darkness to light.)

  22. Supernova A type II supernova, or stellar explosion, occurs when a star of at least eight times our sun's mass runs out of nuclear fuel at its core. (Stars that are more than 250 times more massive than the sun do not explode at the end of their lives; instead they collapse into similarly massive black holes. All atoms > Iron come from Supernova! (Sun & Earth is 4.54 Billion years old)

  23. What are we made of? Campbell We are mostly made of water (H2O): ≈75% C —very versatile: everything made of: Nucleic acids, Proteins, Lipids (fat), Carbohydrates. (Remember these families)! O —bonding, proteins, fats, nucleic acids N — proteins, genetic material Ca, P — bones

  24. What’s so special about Carbon?Carbon is backbone of life • Carbon, along with Oxygen, Hydrogen, Nitrogen, (and Phosphorous) make up “life”. • C is abundant (on earth). • C has 4 valence electrons. • C can make up huge array of C-containing polymers. • C is water-soluble. • C is small size and intermediate energy levels (so enzymes can manipulate). CH4 C2H6 C2H4 Si is alternative, but larger, more stable, tends tends to form crystals. Astrobiology: life elsewhere is probably C-based: carbon chauvinism. http://en.wikipedia.org/wiki/Carbon-based_life

  25. Homework Buy Book (or parts of it)! Read Chpt 1 You will get written homework on Wednesday, Jan 16th. Due following Wednesday, Jan. 23rd!

  26. Evaluate class 1. What was the most interesting thing you learned in class today? 2. What are you confused about? 3. Related to today’s subject, what would you like to know more about? 4. Any helpful comments. Put your name in upper right-corner. Then tear off your name before turning in. (That way you can be brutally honest!) Answer, and turn in at the end of class. (I’ll give you ~5 minutes.)

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