Exploration of Protein Folding
|
|
- Elisabeth Knight
- 6 years ago
- Views:
Transcription
1 Exploration of Protein Folding Question: What conditions affect the folding of a protein? Pre-lab reading Atkins & Jones (5 th ed.): Sections ; ; and Section Safety and Waste Disposal Eye protection should be worn at all times. Aqueous solutions can be washed down the drain with copious amounts of water. Place waste solids in the designated container. Background Proteins are biological molecules that play vital roles in the body. Proteins are responsible for a variety of functions, from making muscles contract to replicating DNA to carrying oxygen to cells. Proteins are made in the body when many amino acids small organic molecules found either in food or produced by the body are bonded together to make a very large molecule in much the same way that beads are strung together to make a necklace. The identity of the protein depends on the number and arrangement of these amino acids. For example, hemoglobin, the protein used by red blood cells to carry oxygen, contains 574 amino acids in a unique order. Depending on the chemical structure of their side chains, amino acids can be classified roughly as polar or nonpolar. The intermolecular forces between these amino acids determine the threedimensional structure of the protein. The protein s three-dimensional structure, in turn, determines the biological function of the molecule. In the case of hemoglobin, the interaction of the amino acids causes the protein to arrange itself in such a way that a binding site is created for oxygen molecules. The environment in which the protein is found also is critical in determining its three-dimensional structure. In aqueous solutions, amino acids that have polar side chains can form relatively strong dipole-dipole attractions or hydrogen bonds with water. These hydrophilic amino acids position themselves on the outside of the three-dimensional protein structure where they can be partially surrounded by water molecules. Since water is not able to form hydrogen bonds or dipole interactions with nonpolar side chains, hydrophobic amino acids are generally found inside the protein structure. The three-dimensional arrangement of the biologically functional protein is called its native structure. Denaturing Proteins There are a variety of ways in which the three-dimensional structure of the protein can be disrupted, that is, ways in which the protein can be denatured. The denatured protein is no longer able to carry out its biological function. Some possible ways in which a protein can be denatured include: 1. Addition of a large quantity of a small polar molecule. The added polar molecule interferes with intermolecular forces between the hydrophilic amino acids and the water by preferentially interacting with water. As a result, these hydrophilic amino acids, normally found on the outside of the protein, interact with other amino acids. These new interactions are weaker than the interactions between water and hydrophilic amino acids and therefore do not normally occur. 2. Addition of a detergent. A detergent is a molecule that has a nonpolar hydrophobic end and a polar hydrophilic end. The nonpolar end of the detergent interacts with the hydrophobic amino acids that are normally buried inside the protein while the polar end of the detergent interacts with the water. Thus the hydrophobic amino acids are pulled to the outside of the protein structure. 3. Increase in temperature. The increase in molecular motion caused by the increase in temperature disrupts molecular interactions.
2 4. Change in ph. Increasing or decreasing the ph changes the charge distribution in the protein and therefore alters the intermolecular forces between the protein and the solvent. 5. Mechanical shock. One example of permanently changing a protein structure by mechanical shock is beating egg whites to form a fluffy white foam (the meringue in lemon meringue pie). The egg white is a solution of albumin, a protein. The albumin is mechanically shocked or beaten until its structure changes and the protein is no longer water soluble. Stabilizing Proteins The three-dimensional structure of the protein can be made more stable by adding ions such as sulfate or phosphate to an aqueous solution containing the protein. Although the reason these anions stabilize the three-dimensional structure is not well understood, it is believed that sulfate and phosphate ions increase the surface tension of the solvent. In order to dissolve a protein in a solvent, a tiny cavity must be created in the solvent for the protein. If it is difficult to create the cavity in the solvent, the cavity will be very small and the protein has to be folded very tightly to fit inside. If it is relatively easy to make the cavity in the solvent, the protein doesn t need to be as tightly folded. Both sulfate ion and phosphate ion increase the surface tension of the solution, thereby making it much more difficult to form a cavity in the water and allowing the protein to remain folded. Detecting Structural Changes Cyanobacteria (commonly known as blue-green algae) contain an elaborate light-harvesting antenna complex in addition to chlorophyll molecules. The complex is made up of approximately 300 chromoproteins that absorb sunlight from 500 to 650 nm, a region of the solar spectrum in which chlorophyll does not absorb. Many health food stores and drug stores now sell dried Spirulina, one type of cyanobacteria, in capsule form as a protein source. As part of its antenna complex, this cyanobacterium contains phycocyanin, a chromoprotein composed of a chromophore called phycocyanobilin and a protein that is attached to the chromophore through the sulfur atom of the amino acid cysteine. Figure 1. The chomoprotein phycocyanin, which is composed of the four-ring chromophore phycocyanobilin and a protein. Phycocyanobilin is shown here in a linear conformation. The color of phycocyanin is strongly dependent upon its environment. In the native (folded) protein, the chromophore is held in a linear conformation by hydrogen bonding to nearby side chains of the protein. The protein acts as a scaffold to hold the chromophore in the desired linear position. If the protein is unfolded (i.e., denatured), the scaffolding of nearby side chains is removed from the phycocyanobilin, which then folds into a cyclic lockwasher conformation. The absorption spectrum of the chromophore in the cyclic lockwasher conformation is very different from the spectrum of the
3 linear conformation. Instead of absorbing in the visible region, the unscaffolded phycocyanobilin absorbs in the ultraviolet at around nm. Therefore, the chromophore indicates the threedimensional arrangement of the protein structure: when in its native form, the chromoprotein has a dark blue color; when the chromophore is unfolded, its blue color fades away. This color can be observed visually and more precisely with a spectrophotometer. In addition to absorption spectroscopy, fluorescence can be used to determine the integrity of the protein structure. When the phycocyanobilin is held in a linear conformation by the protein scaffolding, it displays a red fluorescence that is apparent even in room light. When the chromophore assumes the cyclic lockwasher position, this fluorescence disappears. Recall that this chromoprotein is used by the bacterium to collect photons for photosynthesis. Since in this procedure the chromoprotein has been isolated from the other photosynthetic proteins found in the living organism, these photons cannot be transferred to photosystem II and therefore escape as light in the form of fluorescence. Thus the red fluorescence indicates that the chromoprotein is functioning properly. The lack of red fluorescence means the protein has been denatured, i.e., unfolded. Another visual indication of the denaturing of the chromoprotein is the appearance of a cloudy mixture. When the chromoprotein is not properly folded, the molecules tend to aggregate together and precipitate out of solution. When a protein precipitate forms, the solution will look milky. In this experiment, you will investigate the intermolecular forces at work in aqueous solutions of phycocyanin by examining the specific conditions under which the chromoprotein exists in its native and denatured forms. Spectrophotometry What we see as "color" is the result of the absorption and/or reflection of light of specific wavelengths. White light consists of electromagnetic radiation having wavelengths ranging from 360 nm to 700 nm. When white light strikes a colored object, radiation of certain wavelengths is absorbed. The radiation that is reflected from or transmitted through the object will not contain the absorbed wavelengths, and the object will appear colored. Table I below lists the colors of various wavelengths of visible light: Red- Blue- Red Blue Red- Yellow Blue- Yellow Yellow- Table I. Wavelengths and Corresponding Colors Wavelength (nm) Color red orange yellow green blue violet Figure 2: Color Wheel The color wheel in Figure 2 shows the complementary relationship between colors absorbed by a solution and those transmitted. When a sample absorbs light of a particular color, we perceive the object as the complementary color, i.e., the color opposite the absorbed color on the color wheel. For example, if a sample absorbs red light, the sample will appear blue-green to our eyes.
4 According to theory, the amount of light of a specific wavelength absorbed by a sample depends on 1) the concentration of the absorbing substance in the sample, 2) the thickness of the sample, and 3) the chemical characteristics of the absorbing (colored) species. When the sample is in solution, the relationship among these factors is expressed by Beer's Law: - log T = lc (1) where and T is transmittance, the fraction of incident light that is transmitted is the molar absorptivity, which is a constant characteristic of the absorbing species l is the sample thickness c is the concentration of the absorbing species in solution. The absorbance, A, of a sample is defined as follows: A = - log T = - log (%T/100) (2) The percent transmittance, %T, is 100 times the transmittance. Most instruments report %T rather than T. Substituting the definition of absorbance into Beer's Law yields the useful form: A = lc (3) In this investigation, you will measure the absorbance of a series of protein solutions to investigate how protein structure is affected by adding different amounts of acid to the solution. Measure the absorbance of each solution at 620 nm (orange light, since the protein solution is blue). Terminology Procedure Hydrophilic: having relatively strong intermolecular attraction to water Hydrophobic: having relatively weak intermolecular attraction to water Native structure: the three-dimensional arrangement of a biologically functional protein Denature: the disruption of the three-dimensional arrangement of a protein resulting in loss of the protein s biological function Isolation of phycocyanin from blue-green algae (Spirulina) Each group should do this part of the experiment and obtain a sample of phycocyanin. Once you prepare your sample of phycocynin, add your sample to the beaker at the front of the lab. All lab groups will use this pooled phycocyanin sample for the rest of the lab to ensure that everyone starts with the same concentration of phycocynin. Pour the contents of a blue-green algae (Spirulina) capsule into a clean, dry mortar. Add an approximately equal volume of silica to the mortar and vigorously grind the mixture with a pestle until the mixture has a fine, smooth texture (about 4 minutes). Divide the solid roughly equally between four clean, dry test tubes and add 5 ml of 0.1 M sodium phosphate buffer (ph 7) to each test tube. Stir each solution well using a glass stirring rod and centrifuge the mixtures for about two minutes. Use a disposable pipet to transfer the clear supernatant liquid from the four test tubes to a small beaker (avoid transferring any of the solid material from the test tube). Use this supernatant liquid containing the phycocyanin for the experiments below. Observation of phycocyanin protein fluorescence Observe and record the color of the phycocyanobilin protein. Shine a flashlight up through the bottom of the small beaker containing the protein solution and record your observations.
5 Observation of phycocyanin protein under various conditions Preparation of the Control Sample Use a graduated cylinder to measure 5.0 ml of 0.1 M sodium phosphate buffer (ph 7) into a small test tube. Use a micropipette to deliver 1 ml (1000 L) of phycocyanin solution into the test tube. Mix gently. This tube contains a solution of the intact (native) protein. Record your observations of the color and appearance of the control sample, and retain this solution to compare to the test samples. Remove a small amount of the solution and place it in a cuvette. Measure the absorbance of the sample at 620nm. Preparation of Test Samples Effect of ph You will be assigned two volumes between 0.5 and 5.0 ml of 0.1 M HCl to test. Use a graduated cylinder to deliver your assigned volumes of 0.1 M HCl to two different clean dry test tubes. Use a conditioned glass pipet to deliver enough 0.1 M Phosphate buffer solution to each test tube to bring the total volume up to 5.0 ml. To each test tube, use a micropipette with a clean tip to deliver 1.0 ml of phycocyanin from the class s pooled sample. Record your observations of both color and fluorescence (with the flashlight) for each sample. Be sure to compare the color and the fluorescence with the control sample. When you have recorded the observations for your samples, place your test tubes in a centrifuge for 5 minutes. Compare the samples again with the control and record the observations. Remove a small amount of the solution in the centrifuged sample and place it in a cuvette. Measure the absorbance of the sample at 620nm. The data for all groups sample will be pooled. Be sure to give your results to your instructor. References Atkins, P.; Jones, L. Chemical Principles: The Quest for Insight, 5 th ed.; Freeman: New York Bowen, R.; Hartung, R.; Gindt, Y. M. J. Chem. Educ. 2000, 77, Heller, B. A.; Gindt, Y. M. J. Chem. Educ. 2000, 77, Jones, C. M. J. Chem. Educ. 1997, 74, 1306.
Physical Separations and Chromatography
Lab #5A & B: Physical Separations and Chromatography Individual Objectives: At the end of these experiments you should be able to: Ø Distinguish between Rf and tr; chromatograph and chromatogram; adsorption
More informationPhotosynthesis. Introduction
Photosynthesis Learning Objectives: Explain the importance of photosynthetic pigments for transformation of light energy into chemical bond and the advantage of having more than one pigment in the same
More informationPLANT PIGMENTS AND PHOTOSYNTHESIS LAB
AP BIOLOGY CELLULAR ENERGETICS ACTIVITY #6 NAME DATE HOUR PLANT PIGMENTS AND PHOTOSYNTHESIS LAB OBJECTIVES: After completing this lab you should be able to: 1. separate pigments and calculate their R f
More informationSkill Building Activity 2 Determining the Concentration of a Species using a Vernier Spectrometer
Skill Building Activity 2 Determining the Concentration of a Species using a Vernier Spectrometer Purpose To use spectroscopy to prepare a Beer s Law plot of known dilutions of copper(ii) sulfate so that
More informationAP Biology Lab 4 PLANT PIGMENTS AND PHOTOSYNTHESIS
AP Biology Laboratory Date: Name and Period: AP Biology Lab 4 PLANT PIGMENTS AND PHOTOSYNTHESIS OVERVIEW In this lab you will: 1. separate plant pigments using chromatography, and 2. measure the rate of
More informationLAB 05 Enzyme Action
LAB 05 Enzyme Action Objectives: Name the substrate and products of the peroxidase-catalyzed reaction. To understand the terms: enzyme, activation energy, active site, ph, and denaturation. Distinguish
More informationBiology 1208 Final Study Guide
* If there are any mistakes, fix them! * Laboratory Safety: Always wear closed-toed shoes (Sandals are NOT acceptable footwear) Long hair should be tied back to keep it out of your eyes and away from anything
More informationBuffered Solutions M HC 2 H 3 O 2 (acid) and 0.10M NaC 2 H 3 O 2 (conjugate base) 0.25 M NH 3 (base) and 0.20 M NH 4 Cl (conjugate acid)
Buffered Solutions Objective: Buffering of weak acid/weak base solutions is very important, especially in biological chemistry. In this experiment you will demonstrate the buffer effect to yourself, and
More informationChemistry 118 Laboratory University of Massachusetts Boston Beer s Law
Name: LEARNING GOALS: Chemistry 118 Laboratory University of Massachusetts Boston Beer s Law 1. Become familiar with the concept of concentration and molarity. 2. Become familiar with making dilutions
More informationExperiment 2: The Beer-Lambert Law for Thiocyanatoiron (III)
Chem 1B Dr. White 11 Experiment 2: The Beer-Lambert Law for Thiocyanatoiron (III) Objectives To use spectroscopy to relate the absorbance of a colored solution to its concentration. To prepare a Beer s
More informationLAB #6 Chromatography Techniques
LAB #6 Chromatography Techniques Objectives: To learn how to story board a procedure Explain how a chromatograph of pigments is formed from both paper and thin layer chromatography. Isolate and identify
More information#22 Visible Spectrum of Chlorophyll from Spinach
#22 Visible Spectrum of Chlorophyll from Spinach Purpose: Chlorophyll is extracted from spinach. From a spectrum of the solution produced, the ratio of chlorophyll a and b present is estimated. Introduction:
More informationWestern Carolina University. Chem 132 Lab 04 Introduction to Physical Changes and Chemical Reactions Introduction
Chem 132 Lab 04 Introduction to Physical Changes and Chemical Reactions Introduction This lab serves as an introduction to physical changes. Physical changes involve a change in the form of matter without
More informationExperiment 2: The Beer-Lambert Law for Thiocyanatoiron (III)
Chem 1B Saddleback College Dr. White 1 Experiment 2: The Beer-Lambert Law for Thiocyanatoiron (III) Objectives To use spectroscopy to relate the absorbance of a colored solution to its concentration. To
More informationPhysical and Chemical Properties of Matter Lab
Physical and Chemical Properties of Matter Lab Purpose To introduce the student to physical and chemical properties of matter and their use for the identification and separation of compounds. Each student
More informationExperiment 18 - Absorption Spectroscopy and Beer s Law: Analysis of Cu 2+
Experiment 18 - Absorption Spectroscopy and Beer s Law: Analysis of Cu 2+ Many substances absorb light. When light is absorbed, electrons in the ground state are excited to higher energy levels. Colored
More informationExperiment#1 Beer s Law: Absorption Spectroscopy of Cobalt(II)
: Absorption Spectroscopy of Cobalt(II) OBJECTIVES In successfully completing this lab you will: prepare a stock solution using a volumetric flask; use a UV/Visible spectrometer to measure an absorption
More informationChemistry 112 SPECTROPHOTOMETRIC DETERMINATION OF AN EQUILIBRIUM CONSTANT
Chemistry 112 SPECTROPHOTOMETRIC DETERMINATION OF AN EQUILIBRIUM CONSTANT INTRODUCTION The principle underlying a spectrophotometric method of analysis involves the interaction of electromagnetic radiation
More information1 st European Union Science Olympiad in Dublin, Ireland. task B
1 st European Union Science Olympiad in Dublin, Ireland task B Task B The Properties of Proteins Introduction In this task you will investigate some of the properties of proteins. Proteins consist of a
More informationA Study of Beer s Law Prelab
1. What is the purpose of this experiment? A Study of Beer s Law Prelab 2. Using the absorbance versus wavelength curve given in Figure I, determine the approximate value of max of the dye used to construct
More informationSolution Experiment Collin College
Solution Experiment Collin College Christian E. Madu, PhD and Michael Jones, PhD Objectives Predict the polarity of a molecule using the Lewis Dot Formula and molecular shape. Determine the polarity of
More informationPhysical Properties and Structure of Solids
49 Physical Properties and Structure of Solids INTRODUCTION: Depending on whether the kind of bonding in a pure substance is primarily ionic, covalent or metallic in character, a substance may be described
More informationBiology Unit 2, Structure of Life, Lab Activity 2-2
Biology Unit 2, Structure of Life, Lab Activity 2-2 Photosynthesis is the process by which energy used by living systems is converted from electromagnetic radiation from the sun to chemical energy. This
More informationINTRODUCTION bioactive compounds Pigmentation chromobacteria water soluble water insoluble
INTRODUCTION So far we have witnessed several useful applications of microbes including applications in food and the bioremediation of the environment. Besides consuming the desired substrate (oil) and
More informationChemistry Review. Structure of an Atom. The six most abundant elements of life. Types of chemical bonds. U n i t 2 - B i o c h e m i s t r y
Chemistry Review Structure of an Atom are organized into shells or levels around the nucleus. Atoms are most stable when their outer or valence shell is. The six most abundant elements of life Types of
More informationName Biology Chapter 2 Note-taking worksheet
Name Biology Chapter 2 Note-taking worksheet The Nature of Matter 1. Life depends on Atoms 1. The study of chemistry starts with the basic unit of matter, the. 2. The atom was first used by the Greek philosopher
More informationLec.1 Chemistry Of Water
Lec.1 Chemistry Of Water Biochemistry & Medicine Biochemistry can be defined as the science concerned with the chemical basis of life. Biochemistry can be described as the science concerned with the chemical
More informationPhotosynthesis. Photosynthesis is the conversion of light energy to chemical energy and its subsequent use in the synthesis of organic molecules.
Photosynthesis Photosynthesis is the conversion of light energy to chemical energy and its subsequent use in the synthesis of organic molecules. In its simplest form the process can be expressed as: Carbon
More informationChromatography Extraction and purification of Chlorophyll CHM 220
INTRODUCTION Extraction and purification of naturally occurring molecules is of the most common methods of obtaining organic molecules. Locating and identifying molecules found in flora and fauna can provide
More informationExperiment 2 Solvent-free Aldol Condensation between 3,4-dimethoxybenzaldehyde and 1-indanone
Experiment 2 Solvent-free Aldol Condensation between 3,4-dimethoxybenzaldehyde and 1-indanone Chemical Concepts Carbonyl chemistry, base catalyzed aldol reaction, melting point, recrystallization Green
More informationMOLEBIO LAB #4: Using a Spectrophotometer
Introduction: Spectrophotometry MOLEBIO LAB #4: Using a Spectrophotometer Many kinds of molecules interact with or absorb specific types of radiant energy in a predictable fashion. For example, when while
More informationLab Investigation 4 - How could you make more of this dye?
Lab Investigation 4 - How could you make more of this dye? USING SPECTROSCOPY TO DETERMINE SOLUTION CON- CENTRATION Guiding Question How could you make more of this dye? INTRODUCTION A solution is a homogeneous
More informationTo explore solubilities and reactivities of different metal ions. To identify ions present in unknown solutions using separation methods.
Qualitative Analysis PURPOSE To develop a separation scheme and confirmatory tests for Fe 3+, Ba 2+, and Ag + cations, and to use it to identify the ions in a sample of unknown composition. GOALS To explore
More informationExperiment 7A ANALYSIS OF BRASS
Experiment 7A ANALYSIS OF BRASS FV 10/21/10 MATERIALS: Spectronic 20 spectrophotometers, 2 cuvettes, brass sample, 7 M HNO 3, 0.100 M CuSO 4, 2 M NH 3, two 50 ml beakers, 100 ml beaker, two 25 ml volumetric
More informationWater Hardness and Softening (Bring a water sample from home) Minneapolis Community and Technical College Principles of Chemistry II, C1152 v.2.
Water Hardness and Softening (Bring a water sample from home) Minneapolis Community and Technical College Principles of Chemistry II, C1152 v.2.16 I. Introduction Hard Water and Water Softening Water that
More informationThe light reactions convert solar energy to the chemical energy of ATP and NADPH
10.2 - The light reactions convert solar energy to the chemical energy of ATP and NADPH Chloroplasts are solar-powered chemical factories The conversion of light energy into chemical energy occurs in the
More information9. Solubilities of Ionic and Molecular Substances
9. Solubilities of Ionic and Molecular Substances What you will accomplish in this experiment You ll investigate the like dissolves like rule for predicting the ability of a solute to dissolve in a given
More informationTo observe flame test colors produced by ions in solution.
Flame Tests PURPOSE To determine the identities of ions in two solutions of unknown composition by comparing the colors they produce in flame tests with colors produced by solutions of known composition.
More informationPeroxidase Enzyme Lab
Peroxidase Enzyme Lab An enzyme is a type of protein known as a biological catalyst. A catalyst speeds up chemical reactions by lowering the activation energy required. Enzymes, biological catalysts carry
More informationDETERMINATION OF K c FOR AN EQUILIBRIUM SYSTEM
DETERMINATION OF K c FOR AN EQUILIBRIUM SYSTEM 1 Purpose: To determine the equilibrium constant K c for an equilibrium system using spectrophotometry to measure the concentration of a colored complex ion.
More informationPart II. Cu(OH)2(s) CuO(s)
The Copper Cycle Introduction In this experiment, you will carry out a series of reactions starting with copper metal. This will give you practice handling chemical reagents and making observations. It
More informationPlant Pigments and Photosynthesis. By: Laura Cameron, Sarah Soppe, and Zahra Naseer
Plant Pigments and Photosynthesis By: Laura Cameron, Sarah Soppe, and Zahra Naseer The purpose of the lab was to separate the various pigments in spinach leaves through the process of chromatography. Purpose
More informationChemistry 213. A KINETIC STUDY: REACTION OF CRYSTAL VIOLET WITH NaOH LEARNING OBJECTIVES
Chemistry 213 A KINETIC STUDY: REACTION OF CRYSTAL VIOLET WITH NaOH The objectives of this experiment are to... LEARNING OBJECTIVES study the reaction rate of crystal violet with NaOH using a Spectronic
More informationSAM Teachers Guide Photosynthesis
SAM Teachers Guide Photosynthesis Overview This activity focuses on how certain molecules called pigments interact with light and determine the color of plants. Students explore how molecules such as chlorophyll
More information4.3A: Electronic transitions
Ashley Robison My Preferences Site Tools Popular pages MindTouch User Guide FAQ Sign Out If you like us, please share us on social media. The latest UCD Hyperlibrary newsletter is now complete, check it
More informationChromatography & instrumentation in Organic Chemistry
Chromatography & instrumentation in Organic Chemistry What is Chromatography? Chromatography is a technique for separating mixtures into their components in order to analyze, identify, purify, and/or quantify
More informationIntroduction to Binding Equilibrium Module
IntroductionToBindingEquilibrium.docx Page 1 Introduction to Binding Equilibrium Module Specific information about the spectrophotometer below will change depending on the make and model used. Avidin and
More informationSolutions, Suspensions, and Colloids
Movie Special Effects Activity 3 Solutions, Suspensions, and Colloids GOALS In this activity you will: Explore different ways that materials can be mixed together to make new materials. Test some materials
More informationThe Fluorometric Determination of Acetylsalicylic Acid in an Aspirin Tablet
The Fluorometric Determination of Acetylsalicylic Acid in an Aspirin Tablet Introduction: Fluorescence is the emission of radiation from an atom or polyatomic species after the substance has been exposed
More informationClassifying Chemical Reactions
Classifying Chemical Reactions Prepared by M.L. Holland and A.L. Norick, Foothill College Purpose of the Experiment To make observations when reactants are combined and become familiar with indications
More information#12. Acids and Bases.
#12. Acids and Bases. Goals: To determine the ph of common substances and observe buffer behavior. Background Acids and bases are very common in chemistry and biology. Understanding acids and bases is
More informationStudent Manual. Background STUDENT MANUAL BACKGROUND. Enzymes
Background Enzymes Enzymes are typically proteins (some nucleic acids have also been found to be enzymes) that act as catalysts, speeding up chemical reactions that would take far too long to occur on
More informationScience of Slime. Fig. 1 Structure of poly (vinyl alcohol)
Name: Science of Slime Understanding the structure of a material and how it behaves is a large part of what chemists and materials scientists do for a living. Scientists and engineers cannot use new materials
More informationChapter 7. Photosynthesis: Using Light to Make Food. Lectures by Edward J. Zalisko
Chapter 7 Photosynthesis: Using Light to Make Food PowerPoint Lectures for Campbell Essential Biology, Fifth Edition, and Campbell Essential Biology with Physiology, Fourth Edition Eric J. Simon, Jean
More informationNSW Higher School Certificate Senior Science 9.2 Lifestyle Chemistry
NSW Higher School Certificate Senior Science 9.2 Lifestyle Chemistry Section 2 Cleaning Products 9.2 Lifestyle Chemistry Section 2 ::: Cleaning Products 9.2.2 A wide range of cleaning products are made
More informationStudies of a Precipitation Reaction
Studies of a Precipitation Reaction Prelab Assignment Read the entire lab. Write an objective and any hazards associated with this lab in your laboratory notebook. Answer the following 6 questions in your
More informationChromatography. What is Chromatography?
Chromatography What is Chromatography? Chromatography is a technique for separating mixtures into their components in order to analyze, identify, purify, and/or quantify the mixture or components. Mixture
More information11. Introduction to Acids, Bases, ph, and Buffers
11. Introduction to Acids, Bases, ph, and Buffers What you will accomplish in this experiment You ll use an acid-base indicating paper to: Determine the acidity or basicity of some common household substances
More informationAdhesion Cohesion Surface tension Polarity
Adhesion Cohesion Surface tension Polarity Water molecules have an area that is negatively charged and another positively charged, and this will be responsible for many of the water properties The molecules
More informationSpectrometric Determination of the Acid Dissociation Constant of an Acid-base Indicator
Spectrometric Determination of the Acid Dissociation Constant of an Acid-base Indicator Learning Goals 1. Gain appreciation of the dynamics of perturbing a chemical equilibrium 2. Gain an understanding
More informationIntroduction. Objectives
Experiment: Acids, Bases, and Buffers * Introduction Many common household solutions contain acids and bases. Acid-base indicators, such as litmus and red cabbage juice, turn different colors in acidic
More informationChapter 5, Lesson 1: Water is a Polar Molecule
Chapter 5, Lesson 1: Water is a Polar Molecule Key Concepts The water molecule, as a whole, has 10 protons and 10 electrons, so it is neutral. In a water molecule, the oxygen atom and hydrogen atoms share
More informationPurpose. Procedure. Photosynthesis OVERVIEW:
Photosynthesis OVERVIEW: During lab this week you will perform experiments to help you understand two of the basic processes that convert energy from one form to another in biological systems. Your investigations
More informationProcedure for the Determination of Permanganate Oxidizable Carbon
Procedure for the Determination of Permanganate Oxidizable Carbon Overview: Steve Culman, Mark Freeman, Sieglinde Snapp Kellogg Biological Station, Michigan State University, Hickory Corners, MI, 49060
More informationRate law Determination of the Crystal Violet Reaction Using the Isolation Method
Rate law Determination of the Crystal Violet Reaction Using the Isolation Method Introduction A common challenge in chemical kinetics is to determine the rate law for a reaction with multiple reactants.
More informationPhotosynthesis: Using Light to Make Food
Chapter 7 Photosynthesis: Using Light to Make Food Lectures by Chris C. Romero, updated by Edward J. Zalisko 2010 Pearson Education, Inc. PowerPoint Lectures for Campbell Essential Biology, Fourth Edition
More informationExperiment 13H THE REACTION OF RED FOOD COLOR WITH BLEACH 1
Experiment 13H 08/03/2017 AHRM THE REACTION OF RED FOOD COLOR WITH BLEACH 1 PROBLEM: Determine the rate law for the chemical reaction between FD&C Red Dye #3 and sodium hypochlorite. LEARNING OBJECTIVES:
More informationSolution Chemistry: Making Solutions, Reactions, and Solubility
1 Solution Chemistry: Making Solutions, Reactions, and Solubility ORGANIZATION Mode: laboratory, groups of 4 Grading: goggles, closed-toe shoes, appropriate attire Safety: lab report, individual, due at
More informationTopic 9. Exercises on Photosynthesis. I. Where Photosynthesis Occurs in Plant Cells
Topic 9. Exercises on Photosynthesis The pathways of photosynthesis and respiration are quite different. However, at the global level, one is perfectly complementary to the other as the end products of
More informationLecture-17. Electron Transfer in Proteins I
Lecture-17 Electron Transfer in Proteins I The sun is main source of energy on the earth. The sun is consumed by the plant and cyanobacteria via photosynthesis process. In this process CO2 is fixed to
More informationAcids and Bases. How does ph affect biological solutions? Introduction. Prelab Preparation Review Section 2.3 on acids and bases in your textbook.
Acids and Bases How does ph affect biological solutions? Learning Objectives To relate the ph scale to how acidic or basic a solution is. To explain how a buffer affects the ph of a solution. Process Objectives
More informationBIOL 221 Concepts of Botany
BIOL 221 Concepts of Botany Topic 13: Photosynthesis A. Introduction Through photosynthesis, the abundant energy from the sun is collected and converted into chemical forms by photosynthetic organisms
More informationEXPERIMENT 6. Physical and Chemical Changes Part 2 INTRODUCTION
EXPERIMENT 6 Physical and Chemical Changes Part 2 INTRODUCTION Evidence of chemical change can be the evolution of heat or light, the formation of a gas (seen in Experiment 5), the appearance of a material
More informationSo, What Does it Indicate?
So, What Does it Indicate? Introduction Phenolphthalein is a common indicator you may have used in a previous science course, such as Chemistry 184. In solutions with a ph of less then 8.3, this compound
More informationChapter 2: Chemical Basis of Life
Chapter 2: Chemical Basis of Life Chemistry is the scientific study of the composition of matter and how composition changes. In order to understand human physiological processes, it is important to understand
More informationLife s Chemical Basis
Life s Chemical Basis Life s Chemical Basis Ø Atoms and Elements Ø Why Electrons Matter Ø Atomic Bonds Ø Water molecule properties Ø Hydrogen Power (ph) Matter & Elements Ø Matter is anything that occupies
More informationMinneapolis Community and Technical College. Separation of Components of a Mixture
Minneapolis Community and Technical College Chemistry Department Chem1020 Separation of Components of a Mixture Objectives: To separate a mixture into its component pure substances. To calculate the composition
More informationK sp = [Pb 2+ ][I ] 2 (1)
Chem 1B Saddleback College Dr. White 1 Experiment 11: Determination of K sp Objectives To determine the concentration of an unknown using a Beer- Lambert Plot. To determine the K sp for a relatively insoluble
More informationDrug Delivery with Alginate Dr. J. Vernengo and Dr. S. Farrell
Objectives Drug Delivery with Alginate Dr. J. Vernengo and Dr. S. Farrell Define a hydrogel. Define the chemical structure and ionic crosslinking of alginate to form hydrogels. Discuss the role of hydrogels
More informationChemical Reactions: The Copper Cycle
1 Chemical Reactions: The Copper Cycle ORGANIZATION Mode: pairs assigned by instructor Grading: lab notes, lab performance and post-lab report Safety: Goggles, closed-toe shoes, lab coat, long pants/skirts
More informationph Measurement and its Applications
ph Measurement and its Applications Objectives: To measure the ph of various solutions using indicators and ph meters. To perform a ph titration. To create and study buffer solutions. To determine the
More informationExperiment 12H, Parts A and B
Experiment 12H, Parts A and B AHRM 8/17 PRINCIPLES OF EQUILIBRIUM AND THERMODYNAMICS MATERIALS: PURPOSE: 0.0200 M Fe(NO 3 ) 3 in 1 M HNO 3, 0.000200 M KSCN, 2.0 M HNO 3, solid Fe(NO 3 ) 3. 9H 2 O with
More informationDetermination of an Equilibrium Constant
Last updated 1/29/2014 - GES Learning Objectives Students will be able to: Determine the numerical value of an equilibrium constant from measured concentrations of all reaction species. Use an absorption
More informationKang, Lin-Woo, Ph.D. Professor Department of Biological Sciences Konkuk University Seoul, Korea nd Semester
Kang, Lin-Woo, Ph.D. Professor Department of Biological Sciences Konkuk University Seoul, Korea 2018. 2 nd Semester Absorbance Assay (280 nm) Considerations for use Absorbance assays are fast and
More informationPhotosynthesis and Cellular Respiration
Photosynthesis and Cellular Respiration Introduction... 2 Photosynthesis and Cellular Respiration are energy conversion processes... 2 Photosynthesis and Cellular Respiration are enzyme pathways... 3 Photosynthesis...
More informationDetermining the Concentration of a Solution: Beer s Law. Evaluation copy. Figure 1
Determining the Concentration of a Solution: Beer s Law Computer 17 The primary objective of this experiment is to determine the concentration of an unknown copper (II) sulfate solution. You will use a
More informationMORE LIGHTS, COLOR, ABSORPTION!
Name Partner(s) Section Date MORE LIGHTS, COLOR, ABSORPTION! PRE-LAB QUERIES 1. The terms absorption and transmittance are often used when describing the interaction of light with matter. Explain what
More informationThermodynamics and the Solubility of Sodium Tetraborate Decahydrate
Thermodynamics and the Solubility of Sodium Tetraborate Decahydrate In this experiment you, as a class, will determine the solubility of sodium tetraborate decahydrate (Na 2 B 4 O 7 10 H 2 O or Na 2 [B
More informationEXPERIMENT 8 Determining K sp
EXPERIMENT 8 Determining K sp Introduction The solubility product constant, or K sp of a compound is an equilibrium constant that describes the degree to which a solid dissolves in water. The K sp is calculated
More informationCopy into Note Packet and Return to Teacher
Copy into Note Packet and Return to Teacher Section 1: Nature of Matter Objectives: Differentiate between atoms and elements. Analyze how compounds are formed. Distinguish between covalent bonds, hydrogen
More informationPhotosynthesis Lecture 7 Fall Photosynthesis. Photosynthesis. The Chloroplast. Photosynthetic prokaryotes. The Chloroplast
Photosynthesis Lecture 7 Fall 2008 Photosynthesis Photosynthesis The process by which light energy from the sun is converted into chemical energy 1 Photosynthesis Inputs CO 2 Gas exchange occurs through
More informationPrinciples of Thin Layer Chromatography
REVISED & UPDATED Edvo-Kit #113 Principles of Thin Layer Chromatography Experiment Objective: The objective of this experiment is to gain an understanding of the theory and methods of thin layer chromatography.
More informationThin Layer Chromatography
Experiment: Thin Layer Chromatography Chromatography is a technique widely used by organic chemists to separate and identify components in a mixture. There are many types of chromatography, but all involve
More informationBis sulfone Reagents. Figure 1.
Bis sulfone Reagents An intact IgG molecule has four accessible inter chain disulfide bonds that can be reduced to form eight free cysteine thiols, which can serve as sites for conjugation. The reaction
More informationCHAPTER 2. Life s Chemical Basis
CHAPTER 2 Life s Chemical Basis The Chemistry of Life We are made up of elements. Atoms of one kind make up an element. Atoms are the smallest unit of an element still maintaing the element s properties.
More informationEXPERIMENT 14. ACID DISSOCIATION CONSTANT OF METHYL RED 1
EXPERIMET 14. ACID DISSOCIATIO COSTAT OF METHYL RED 1 The acid dissociation constant, Ka, of a dye is determined using spectrophotometry. Introduction In aqueous solution, methyl red is a zwitterion and
More informationExperiment 7: SIMULTANEOUS EQUILIBRIA
Experiment 7: SIMULTANEOUS EQUILIBRIA Purpose: A qualitative view of chemical equilibrium is explored based on the reaction of iron(iii) ion and thiocyanate ion to form the iron(iii) thiocyanate complex
More informationSo, What Does it Indicate?
So, What Does it Indicate? Introduction Phenolphthalein is a common indicator you may have used in a previous science course, such as Chemistry 130 or Chemistry 170. In solutions with a ph of less then
More informationDetermining the Concentration of a Solution: Beer s Law
Determining the Concentration of a Solution: Beer s Law Vernier Spectrometer 1 The primary objective of this experiment is to determine the concentration of an unknown copper (II) sulfate solution. You
More informationWater is one of the few compounds found in a liquid state over most of Earth s surface.
The Water Molecule Water is one of the few compounds found in a liquid state over most of Earth s surface. Like other molecules, water (H2O) is neutral. The positive charges on its 10 protons balance out
More information