...Lab 2 Cell Structure and Cell Transport-14 Name __ carson held__________________ Introduction: The cell is the basic unit of structure of all living organisms. The cell carries out the functions required for the organism to reproduce, protect itself, metabolize food, move, produce substances to support the entire organism. In this experiment, you will explore the cell membrane’s role in allowing materials to enter or leave the cell. This is a vital function of the cell membrane. Using the Physio Ex CD 9.0, you will be able to conduct experiments showing the important cell membrane processes of diffusion, osmosis, filtration, and active transport. The simulations will allow you to alter conditions to show the effect of concentrations, pore size, pressure, carrier, and ATP have on movements of materials through the cell membrane. Purpose: To conduct experiments showing the effects of concentration, ions, and particle size of movement through the cell membrane. Materials: Lab manual, PhysioEx 9.0 Procedure: Cell Transport Mechanisms and Permeability in the lab manual. You will also need the PhysioEx 9.0 CD for this lab. Read over exercise overview and introduction. Complete the following questions from the exercise as you complete the simulation exercises. Go to Exercise 1 Cell Transport Mechanisms and Permeability on the CD. Follow the directions and complete each part. Answer questions or fill in tables as...
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...Marisa M Souza AP Biology Mrs.Therrien October, 6, 2015 Diffusion and Osmosis Exercise 1A: Diffusion In our diffusion experiment glucose is leaving the bag and Iodine-Potassium-Iodide or IKI is entering the bag. The change in color within the bag indicates the presence of glucose. The IKI moved from the beaker into the dialysis bag, this resulted in a change of color to black within the bag. This made the concentration within the bag equal to the concentration outside the bag. The glucose solution moved out of the bag making glucose present in the beaker. The glucose moved to make the solute concentration inside and out equal. If the initial and final % concentration of glucose and IKI for in the bag and in the beaker were given they...
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...Exp’t 112 Isolation of Casein, Lactose, and Albumin from Milk Adapted by R. Minard (Penn State Univ.) from Introduction to Organic Laboratory Techniques: A Microscale Approach, Pavia, Lampman, Kriz & Engel, Saunders, 1990. Revised 3/20/2000 PreLab Exercise: Draw a mechanism for the acid-catalyzed hydrolysis of the acetal bond in lactose; see reaction below. Hint: your textbook may be of some help; first identify the functional group that is undergoing a reaction and consider the catalyzed used. H HO OH CH2OH O O H OH H2C OH O HO HO OH OH H2C OH O HO HO + HO OH H2O OH CH2OH O HO H + D -Galactose D -Glucose OH α-Lactose: D -Galactose+ D -Glucose Introduction: The Chemistry of Milk Milk is a food of exceptional interest. Not only is milk an excellent food for the very young, but humans have also adapted milk, specifically cow’s milk, as a food substance for persons of all ages. Many specialized milk products like cheese, yogurt, butter, and ice cream are staples of our diet. Milk is probably the most nutritionally-complete food that can be found in nature. This property is important for milk, since it is the only food young mammals consume in the nutritionally significant weeks following birth. Whole milk contains vitamins (principally thiamine, riboflavin, pantothenic acid, and vitamins A, D, and K), minerals (calcium, potassium, sodium, phosphorus, and trace metals), proteins (which include all the essential amino acids), carbohydrates (chiefly lactose), and lipids...
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...(Simple Diffusion) Lab Report Pre-lab Quiz Results You scored 100% by answering 4 out of 4 questions correctly. 1. The driving force for diffusion is You correctly answered: b. the kinetic energy of the molecules in motion. 2. In diffusion, molecules move You correctly answered: a. from high concentration to low concentration. 3. Which of the following dialysis membranes has the largest pore size? You correctly answered: d. 200 MWCO 4. Avogadro's number is a constant for the number of You correctly answered: b. molecules. 01/14/16 page 1 Experiment Results Predict Question: Predict Question 1: The molecular weight of urea is 60.07. Do you think urea will diffuse through the 20 MWCO membrane? Your answer : c. No, not at all. Predict Question 2: Recall that glucose is a monosaccharide, albumin is a protein with 607 amino acids, and the average molecular weight of a single amino acid is 135 g/mole. Which of the following will be able to diffuse through the 200 MWCO membrane? Your answer : b. both glucose and albumin Stop & Think Questions: The reason sodium chloride didn't diffuse left to right is that You correctly answered: c. the membrane pore size was too small. Glucose is a six-carbon sugar. Albumin is a protein with 607 amino acids. The average molecular weight of a single amino acid is 135 g/mole. There is no reason to run these solutes at the 20 MWCO because You did not answer this question. Correct answer: d. glucose and albumin are both...
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...In our lab, we were able to witness the process of osmosis and diffusion through dialysis tubing, starch, glucose, iodine, and water. The reason we chose to use these materials is because the dialysis tubing could act as a selective permeable cell membrane to view which molecules are able to pass through and which weren’t. We used the starch, since it is a polymer, and found out that it could not pass though the membrane. We used the glucose, which is a monomer, and found that it was easily able to go into a state of equilibrium with the water. The monomer was able to pass through the dialysis tubing due to its small size and the polymer was not due to its large size. This was what we had predicted in our hypothesis except for the fact that although the glucose did pass through the membrane it did not completely pass through only some of it to create equilibrium. In the starch and iodine solution it was the iodine which was allowed to pass thought the starch was not able to due to its large size further explaining why the water had eventually turned almost clear again compared to its brown looking initial state and the inside of the membrane had turned almost completely blue compared to the clear color it was before. When measuring the glucose both inside and out of the membrane we found that they both had some glucose in it, and although we could not visibly see the changes, it was noticed that the diffusion had occurred and since there was some glucose in each it is safe to...
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...through a selectively permeable membrane. Water will diffuse from the place with higher concentration to the place with a lower concentration. Water goes through the concentration gradient. Which is when molecules without energy diffuse from the place with higher concentration to the one with lower (1). The ability to diffuse through water all depends on the size of the molecule as well. For example, starch is a large molecule therefor it should not fit through the cells membrane. Starch is a polysaccharide because it is comprised of lots of sugars. Individually these glucose molecules are able to pass through the cells membrane but due to the amount of them in starch it can not pass through. Amylase is an enzyme that catalyses the hydrolysis (splitting of a compound by addition of water molecules) of starch into sugars (1). Amylase breaks the starch down into smaller sugar molecules going from C6 H10 O5 to glucose which is C6 H12 O6. The...
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...Introduction Most aspects of a cell depend on the fact that atoms and molecules have kinetic energy and are constantly in motion. Kinetic energy causes molecules to bump into each other and move into different places. Diffusion is the random movement of molecules from an area of higher concentration to an area of lower concentration. Cells have selectively permeable membranes that only allow the movement of certain solutes. Diffusion is vital for many of life’s functions in a cell. It allows oxygen and carbon dioxide exchange in the lungs and between the bodies of intracellular fluid and cells. An example of this process is the diffusion of a smell in a room. Eventually dynamic equilibrium will be reached. This means that the concentration...
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...Diffusion And Osmosis Introduction: There are several valuable aspects of this lab that must be understood before it is conducted. The first of these concepts is called diffusion. Molecules are constantly moving and as they are moving they tend to move from areas of higher concentration to areas of lower concentration. Diffusion can be defined as the net movement of molecules from higher to lower concentrations. One example, of diffusion is when an item like perfume is opened in a room. Shortly after it is opened the smell can be detected throughout the entire room. Diffusion can occur through a membrane such as that of a cell which explains how something can enter the cell. One special type of diffusion is called osmosis or the diffusion of water. Osmosis describes how water moves through a membrane from areas that have high water potential to areas that have lower potential. Water potential is defined as the measure of free energy of water in a solution. Biologists use this term to help describe why water moves from one area to another. Water potential can be affected by two major aspects pressure and the amount of solute. Water potential can be calculate by the pressure potential added to the solute potential. In order to calculate the solute potential one must multiply the ionization constant, the molar concentration, the pressure constant, and the temperature. When looking at a solution one can categorize it into several different relationships based...
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...across membranes, expending adenosine triphosphate (ATP) (biological energy) to accomplish the movement. Other substances move passively, without expenditure of ATP from the cell, but only if the cell membrane is permeable to those substances. Water and selected solutes move passively through the cell and cell membranes by diffusion, a physical process in which molecules move from an area where they are in high concentration to one where their concentration is lower. The energy driving diffusion comes only from the intrinsic kinetic energy in all atoms and molecules. If nothing hinders the movement, a solute will diffuse until it reaches equilibrium. EXERCISE 1. Diffusion of Molecules Through a Selectively Permeable Membrane Materials string or rubber band 500 – mL beaker one-third filled water sharpie handheld test tube holder 30 % glucose solution 3 standard test tubes starch solution disposable transfer pipettes I2KI solution 2 400 – mL beakers to hold dialysis bag Benedict’s reagent 30 – cm strip of moist dialysis tubing hot plate Introduction Dialysis tubing is a membrane made of regenerated cellulose fibers formed into a flat tube. If two solutions containing dissolved substances of different molecular weights are separated by this membrane, some substances may readily pass through the pores of the membrane, but others may be excluded. Working in groups of four students, you will investigate the...
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...What did caffeine and ethanol do to the heart rate of Daphnia? Increasing the concentration of ethanol in Daphnia decreases heart rate. Increasing the concentration of caffeine in Daphnia increases heart rate. Independent vs. Dependent Variable Independent Variable: One or more factors that the scientist varies during the experiment. Dependent Variable: A feature that the scientist measures in order to determine if it changed in response to the independent variable. What solutions were used to test for the 4 types of organic molecules? Iodine- Polysaccharide Benedict’s Reagent- Sugar Biuret Test- Protein Brown Paper Test- Lipids Vegetable Oil- Solubility of Lipids What does a positive test look like? -Iodine test for polysaccharide: dark purple/black/blue -Vegetable Oil test for solubility of lipids: 1 layer -Biuret test for protein: violet color -Benedict’s Reagent for sugar: very high concentration/orange-red How do you convert Celsius to Fahrenheit and vise versa? ...
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...DETERMINATION OF CONCENTRATION OF MONOSACCHARIDES BY POLARIMETRY Background Polarimetry is is a very useful method to analyze chiral substances. The magnitude and direction of rotation of the plane of lineraly polarized light by a chiral compound is a specific physical property of the compound that can be used to characterize it. Most biomolecules are chiral and hence rotate polarized light. In this experiment you will study the optical rotation of a series of mixed monosaccharide solutions and determine the relative concentrations of them. The instrument used to study optical rotation in chiral molecules is called a polarimeter. A polarimeter takes light vibrating in all planes, isolates the light vibrating in a single plane, projects the light through a tube filled with a solution of chiral compound, and measures the amount of rotation. The observed angle of rotation of the plane of polarization by an optically active liquid, solution, or (more rarely) gas or solid is usually denoted by the symbol α. The angle may be either positive (+) or negative (-) depending on whether the rotation is clockwise, that is, to the right (dextro) or counterclockwise, that is, to the left (levo) as seen by an observer towards whom the beam of polarized light travels (this is opposite from the direction of rotation viewed along the light beam). Biot discovered that the observed rotation is proportional to the length l of the cell or tube containing the optically active liquid or solution...
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...BIOS256 Week 5 Lab Exercise Renal Absorption and Secretion To complete this worksheet, select: Module: Balancing Fluids Activity: Animations Title: Renal Absorption and Secretion Introduction 1. Where does renal absorption and secretion occur? Renal Tubules 2. Define what happens during these processes. a. Absorption: Returns materials to the bloodstream thereby conserving those materials. b. Secretion: Moves materials from the blood stream into the tubule for eventual disposal. 3. Because of very high glomerular filtration rates, nearly the entire volume of the blood enters the renal tubules every 30 minutes. Obviously, most of it must be reabsorbed to avoid dehydration. a. What part of the tubule achieves most of the reabsorption? In the proximal convoluted tubule. b. Where does further reabsorption and “fine tuning” occur? In the rest of the nephron. 4. a. Describe paracellular reabsorption. Paracellular reabsorption is the mechanism where substances diffuse between cells. b. Describe transcellular reabsorption. Transcellular reabsorption is the mechanism whereby the substances pass through the cell. c. What kind of transport mechanisms are used for reabsorption? Transcellular reabsorption is the mechanism whereby the substances pass through the cell. 5. a. Identify two reasons that make secretion important...
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...Cell Membrane Transport Harjot Dhesi Zoology 2011-13 Amon Gekombe 17 February 2014 Introduction The human body must maintain a balance within itself in order to abstain from disturbances caused by the external environment, for example a sudden increase in the outside temperature, or even the internal environment of the body, such as a dramatic drop in blood pressure. The body maintains this equilibrium through various methods and regulators, beginning in the cellular level. The human cell has a selectively permeable plasma membrane, allowing only certain substances to easily pass through to reach the inside or outside of the cell. Small, uncharged, and nonpolar molecules pass with the most ease through the plasma membrane (Tortora and Derrickson 2012). The constant moving in and out of substances is crucial in sustaining the life of the cell. Tortora and Derrickson explain in their book Principles of Anatomy and Physiology that, “Certain substances must move into the cell to support metabolic reactions. Other substances that have been produced by the cell for export or as cellular waste products must move out of the cell” (Tortora Derrickson 2012). Because of the selectively permeable nature of its plasma membrane, the cell can retain chemicals that have a difference in concentration on the inside than on outside of the cell. This is called the concentration gradient. A substance can either move against its concentration gradient by an active process, which requires...
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...biomolecules), are often exceptionally slow: often hours or days, and sometimes even years are required before equilibrium is reached. Yet life requires seconds or even fractions of seconds to produce the same results, and it does this through the use of biological catalysts called enzymes. Enzymes are proteins with special clefts or pockets in their structures in which the reactions occur: the tremendous advantage that enzymes have is that these pockets, by nature of their shape and chemical environment, force the reactants to form transition states much lower in energy than the transitions states the reactants would form under other circumstances, say in solution. Thus, life can subsist at a reasonable pace and it does not take us a week to walk across a room or digest an apple. Of the many kinetic models for enzymes currently used, the first (and simplest) developed is the Michaelis-Menten Model, developed in 1913 by Leonor Michaelis and Maud Menten, which is still quite useful today. One of its early triumphs was the successful explanation of the kinetics of sucrase, or β-fructofuranidase, an enzyme found in yeast which cleaves sucrose (common table sugar) into glucose and fructose, and it is this process that will be the focus of our lab. Theory The overall reaction catalyzed by sucrase is: (1) where S is sucrose, E is the enzyme, and G and F are glucose and fructose, respectively. The overall rate law for the rate of reaction, r, predicted by the Michaelis-Menten...
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...MY BIOLOGY S.B.A Lab #1 Topic: Classification Aim: To classify organisms into groups Apparatus: Method: A list of 10 organisms in my school environment was made and observed. A table was constructed to show the organism and their visible characteristics. Another table was constructed to show the kingdom, phylum and class to which the organisms belong. Observation Organism | Visible Characteristics | Bird | They are vertebrates with a pair of wings. They also have a beak | Cat | They are vertebrates that have sharp claws, a smooth coat of hair (fur) and panted teeth | Earth Worm | Has a long, ring-like segmental body, lives in the soil, has a clitellum | Lizard | Has a scaly skin, 2 pairs of legs | Crab | Has a hard exo-skeleton, has claws, four pairs of jointed legs, seen in wet places | | | Plants | | Pine | Has stems, roots and leaves, produces seed that grow inside cones | Fern | Has roots, stems and leaves, has spores on the underside of the leaves, does not have flower | Hibiscus | Produces flowers, has root, stems and leaves | Leaf of Life | Does not produce flower, has roots, stems and leaves | Mahogany | Has roots, Stems and leaves | | Organism | Kingdom | Phylum | Class | 1 | Bird | Animalia | Chordata | Ares | 2 | Cat | Animalia | Chordata | Mammalia | 3 | Earthworm | Animalia | Chordata | | 4 | Lizard | Animalia | Chordata | Reptilia | 5 | Crab | Animalia | Chordata | Crustacea | Plants 1 | Pine | Plantae...
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