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Can Glucose Pass Through Dialysis Tubing

Diffusions And Osmosis Lab

Diffusions And Osmosis Lab

15 mL 15% Glucose/1% Starch solution in a medicine cup 1. Fill cup with distilled water within 1-2 cm of the top of the cup 2. Dip a glucose test strip into the water in the cup for 1-2 seconds. Run the test strip along the edge of the cup to remove any excess liquid. 3. Wait 2-3 minutes to observe any color change on the strip. A positive (+) glucose test is indicated by a greenish color on the test strip. No color change will occur if the test result is negative (-). Record on Data table 4. Use a plastic pipet add 20-25 drops of the starch indicator solution (Iodine) to the water in the cup. 5. Observe (take a picture) as it mixes with the water. Record the color of the water in Data table 1. 6. Gently rub the tubing between your fingers to open it. 7. Tie one end of the tubing tightly with a piece of string. Fill the tubing with water and test it for leaks at a sink then empty the tubing. 8. Insert the funnel tip into the open end of the dialysis bag, and pour the 15 mL of 15% glucose/1% starch solution from the medicine cup into the tubing. 9. Squeeze all the air bubbles out of the tubing and tie the open end shut with another piece of string. Note the color of the starch-glucose solution in the dialysis tubing and record in Data table 10. Rinse the outside of the bag under running water. Squeeze the bag gently to ensure that there are no leaks. Adjust the string if there are leaks. 11. Completely submerge the model cell into the cup of water and starch indicator solution. Allow osmosis and diffusion to occur for 30 min. 12. After 30 min test the water in the cup for sugar content as in Step 2. Note any color changes in the dialysis tubing and in the cup (take a picture). Record in Data table 1. 13. Wash your hands and clean up your area. Hypothesis: I predict that Continue reading >>

Lab #3 - Membrane Transport

Lab #3 - Membrane Transport

Lab #3 - Membrane Transport Lecture Notes In todays experiments we will explore membrane transport processes, focusing on passive transport, specifically diffusion of molecules through various types of matter and across semipermeable membranes Diffusion - the movement of molecules/atoms from an area of high density/concentration to an area of low density/concentration all particles have kinetic energy; they vibrate and move randomly, in what is known as Brownian Motion - as particles move, they bump into each other and disperse, naturally moving into areas of lower concentration, until eventually there is no net diffusion occurring - this is known as equilibrium the rate of diffusion can depend on several factors; one of these factors is the state of matter that the particle is in - instructors demonstration Questions: diffusion is faster in what type of matter - gas, liquid or solid? Which state of matter has the highest kinetic energy? Which state has the most space between the particles? During the instructors demonstration - keep in mind, what is the difference in time scale (seconds, minutes, hours?) for diffusion in a gas vs. liquid vs. solid? Diffusion also depends on temperature - instructors demonstration - hypothesize - in which solution will the dye move faster? Why? Which solution has the greater kinetic energy? Diffusion can also depend on the size or molecular weight of the particle - looking at the agarose plate, you can come up with a hypothesis about which particle has the highest molecular weight, and which the lowest, based on rates of diffusion - was your hypothesis correct? If not, what other characteristics of the molecules may have influenced their rates of diffusion? Rates of diffusion also depend on the steepness of the concentration gradient - Continue reading >>

Permeability

Permeability

In this exercise you will focus on diffusion, passive movement, osmosis, anddialysis. The four are closely related, but not synonymous. They are vitalprocesses in living organisms, and understanding them helps one understand manyfeatures of human body function, such as blood pressure, how kidneys cleanseblood, why drinking sea water can be dangerous, and how an enema works. Toprepare for this, you should study the material on diffusion, passive movement,osmosis, and dialysis in your textbook and lecture notes. Diffusion is the movement of molecules or ions from a region in whichthey are more concentrated to a region in which they are less concentrated.Note that membranes are not in the definition. Direction of movement is downthe gradient (= with the gradient). Passive movement is diffusion ofmolecules or ions through a selectively permeable membrane. That is, theions or molecules in question will move through a membrane from the region oftheir greater concentration to the region of their lower concentration (downthe gradient). In a biological setting it will almost always be movement ofmolecules or ions in solution that are of interest. That may bediffusion of a type of molecule from place to place within a cell compartment(without passing through a membrane) or, more often, it will be movement of atype of molecule from one solution to another solution through a membrane.*Passive movement and diffusion are not synonyms.* For instance, a gas such asmethane may diffuse through the air (a mixture of other gases) in a roomwithout any involvement of a membrane. Osmosis is the special case of passive movement in which it is the solventmolecules (water, in living systems) whose movement through a membrane isthe point of interest. Biological membranes are freely permeable to Continue reading >>

Osmosis - Uw Dept. Of Chemistry

Osmosis - Uw Dept. Of Chemistry

saturated salt solution (about 1g NaCl/mL of water) Cut about 6 inches of dialysis tubing and soften it in water. Tie one end of the dialysis tubing in a double knot to make a leak proof bag. Secure the buret to a stand. Slide the open end of the dialysis bag around the 50 mL buret and pull the bag up so that the bag and tubing overlap for about one inch. Secure the bag around the buret using a rubber band. Use food coloring to color about 100 mL of saturated salt solution and then add the salt solution to the dialysis bag by pouring it through the top of the buret. The bag should be filled with salt solution. Immerse the bag in a beaker of saturated salt solution until classtime. To present the demo, Remove the beaker of saturated salt solution and immerse the bag in deionized water. Water will pass through the membrane into the bag causing the liquid level in the buret to rise. The dialysis tubing is a semipermeable membrane. Water molecules can pass through the membrane. The salt ions can not pass through the membrane. The net flow of solvent molecules through a semipermeable membrane from a pure solvent (in this cause deionized water) to a more concentrated solution is called osmosis. Continue reading >>

Bio Lab: Does Glucose Pass Through The Dialysis Tubing?

Bio Lab: Does Glucose Pass Through The Dialysis Tubing?

Bio lab: does glucose pass through the dialysis tubing? Here's the big picture, there's this dialysis tubing with starch and 40% glucose and some water. This tubing is submersed in a solution of iodine + water in a beaker. I know that iodine gets into the tubing and starch doesn't get out of it, but does glucose? Thanks Are you sure you want to delete this answer? Best Answer: Glucose does pass through the dialysis tubing, but there is also an equal amount of glucose from the dialysis fluid entering the blood in the dialysis tubing. We say that there is no NET change in glucose concentration in the blood. This is because there is an equal concentration of glucose in the bloof and dialysis fluid. Hence, the glucose concentration of the blood will be the same when it leaves and re-enters the body. Only urea and excess salt pass through the dialysis tubing. Proteins and blood cells and other large components of blood are too large to pass through the semi-permeable dialysis tubing, hence they remain in the blood. Source(s): AVOID Kidney Dialysis Naturally - It does not pass through because it is quite a large molecule c6h12o6 as an equation . Also the body needs it for respiration so the dialysis machine is designed to make it stay in the blood. It does not pass through because the dialysis fluid is a sugar solution made up of glucose and therefore it is at equilibrium with the blood and no glcose diffuses throught the permeable membranes. Hope I helped! Bio lab: does glucose pass through the dialysis tubing? Here's the big picture, there's this dialysis tubing with starch and 40% glucose and some water. This tubing is submersed in a solution of iodine + water in a beaker. I know that iodine gets into the tubing and starch doesn't get out of it, but does gluco Continue reading >>

Science Experiment : Diffusion And Osmosis

Science Experiment : Diffusion And Osmosis

Science Experiment : Diffusion and Osmosis My course is designed to prepare students for the New York State Living Environment Regents exam.During our unit of study on diffusion and osmosis, my students learn that all cells contain membranesthat are selectively permeable, allowing certain things to pass into and leave out of the cell. They learnthat diffusion is the process in which molecules of a substance move from an area of high concentrationto areas of low concentration. Osmosis is the process in which water crosses membranes from regionsof high water concentration to areas with low water concentration. While molecules in diffusion movedown a concentration gradient, molecules during osmosis both move down a concentration gradient aswell as across it. Both diffusion and osmosis are types of passive transport, which do not require help inthe form of energy. The cell membrane determines what substances can diffuse into a cell. This characteristic of a cellmembrane is called its permeability. Many cells are selectively permeable some substances can passthrough the membrane but others cannot. Dialysis tubing is an artificial semi-permeable membranewith similar properties to the cell membrane. The students were conducting an experiment to investigate the selective permeability of dialysis tubing.We tested the permeability of the tubing to glucose, starch and iodine (potassium iodide). The dialysistubing was clipped to form a bag so that glucose and starch was fed into the bag through the other end,and was also clipped to avoid the seeping of the solution.Water with several drops of iodine added to it until it was visibly yellow-amber was added to a 400mlbeaker. The bag was then placed in the beaker, which was stirred with a magnetic stirrer. It was leftthere for 30 minu Continue reading >>

Dialysis Lab Quiz Flashcards | Quizlet

Dialysis Lab Quiz Flashcards | Quizlet

Used medically to separate molecular components of a solution based on the size of the molecules Dialysis tubing has physical characteristics similar to a __________ Starch turns will turn ____ when mixed with iodine Positive Benedict's test for glucose results in an ______ precipitate after heating Starch molecules were too _____ to pass through dialysis tubing Starch molecules are _____ while glucose molecules are ______, which makes them smaller than starch Just _____ would be a good control run for the Benedict's glucose test since it absolutely has no glucose in it Iodine went _____ the tubing, which turned the contents of the tubing blue Starch was ______ the tubing, which resulted in only the inside of the tubing turning blue Glucose ____ through the tubing and went into the iodine and water solution The Benedict's glucose test was ______ for glucose When particles move from one area of high concentration to an area of low concentration (of the particles) When water passes through the cell membrane Osmosis did occur since _____ did pass through the dialysis tubing (solution with iodine went into tubing and turned starch blue) If an amylase enzyme was added (breaks down starch), starch would be able to pass through the cell membrane and turn the _____ of the tubing blue Continue reading >>

Osmosis - Why Is Dialysis Tubing Impermeable To Sucrose When It Should Retain >12,000 Da? - Chemistry Stack Exchange

Osmosis - Why Is Dialysis Tubing Impermeable To Sucrose When It Should Retain >12,000 Da? - Chemistry Stack Exchange

Why is dialysis tubing impermeable to sucrose when it should retain >12,000 Da? While writing up a lab for biology, I realized that the dialysis tubing for sale online seemed to retain large molecules (12-14,000 Da) but didn't specify an upper bound. I learned that the tubing is impermeable to Sucrose , molecular weight 342 Da, because it's too big. This doesn't make sense to me; the site says the tubing "retains >12,000 Da molecules", but Sucrose is clearly smaller than that. So either A) Sucrose does indeed pass through dialysis tubing and I misheard/mis-learned or B) my class used tubing with much smaller pores. So it seems that we used tubing with smaller pores and there is a discrepancy between the metric I was using to compare and the size of the molecules. Thank you to both answers. Maddy Byahoo Oct 13 '12 at 4:06 There exist many types of semi-permeable membranes (the ones used for dialysis tubing), with various pore sizes. One of the very common lab experiment on the topic of osmosis is using a sucrose solution (sucrose is cheap) and small-pores membrane, such that water and small ions (typically Na+ and Cl) can pass, but not sucrose. The one which you link to simply happens to be a variety with much wider pores. Dialysis tubing (and most semi-permeable membranes) operate based on differences of size and not molecular weight. While the size of a molecule or ion does increase as its molecular weight increases, there is some nonintuitive size-mass discrepancies that can occur. Many of these discrepancies are well known to polymer chemists. Most of the ways that we attempt to measure the average molecular weight of a polymer sample are actually measures of average molecular size. The shape that a molecule adopts in solution greatly impacts its apparent size. A po Continue reading >>

Act Science - Dialysis Tubing As A Cell Membrane

Act Science - Dialysis Tubing As A Cell Membrane

In cells, diffusion is the movement of a substance from high concentration to low concentration across the cell membrane, which is a semi-permeable barrier. This means that the membrane allows some things, but not all, to pass through. The permeability of a substance depends on various factors, such as the size of a substance. Objects that are too large cannot pass through the membrane on their own and require a protein channel for passage. Osmosis is a special type of diffusion in which water moves across a semi-permeable membrane. Water moves from an area of high water concentration and low solute concentration to an area of low water concentration and high solute concentration. Diffusion and osmosis occur to balance the concentrations of substances on either side of the membrane that divides them. The following studies were conducted to investigate diffusion and osmosis in cells. Dialysis tubing was used to create a small bag that was filled with various solutions. The material of the dialysis tubing was semi-permeable to small substances, but not to large substances. The dialysis tubing bags were submerged in a beaker with a different solution for 24 hours. Solutions included distilled water, glucose (permeable to the membrane), sucrose (not permeable), or starch (not permeable). Percent change was calculated to determine the percent mass gained or lost by each bag. Continue reading >>

Diffusion Through Dialysis Tubinglab

Diffusion Through Dialysis Tubinglab

The purpose of this lab was to observe the diffusion of iodine and glucose through dialysis tubing. Dialysis tubing is a type of semi-permeable membrane tubing, made mostly of cellulose. In medicine, it can be used to remove toxins from a persons blood because it allows some particles to pass through it, but blocks others. In this lab, the dialysis tubing represented a cell membrane. Diffusion is the process where substances move from places of higher concentration to places of lower concentration. When iodine and starch mix, a chemical reaction occurs that stains the starch blue-black. I predict that the dialysis tubing will as a semi-permeable membrane, allowing the iodine and glucose solutions to diffuse through it. First, we sealed one end of a moist dialysis tube by tying it into a knot. We then filled this tube with a starch solution and sealed the other end the same way. Next, we placed the dialysis tube into a beaker filled with distilled water. Finally, we added 25 drops of an iodine solution into the distilled water and waited for the solutions to diffuse. We observed any changes that occurred. We got another dialysis tube and sealed one end like before, but this time, we filled it with a glucose solution. We sealed the other end then placed the tube in a beaker filled with distilled water. We waited for the glucose molecules to diffuse, then dipped a glucose test strip into the distilled water. The starch in our first dialysis tube turned blue-black, but there were no noticeable color changes in the iodine solution. This led me to conclude that the iodine molecules from the iodine solution were passing through the dialysis tube into the starch solution and staining it blue-black, but the starch molecules were not able to pass through the dialysis tube, becau Continue reading >>

How Do Substances Move Across A Selectively Permeable Membrane?

How Do Substances Move Across A Selectively Permeable Membrane?

BIOL 1406 PreLab 5.2 A selectively permeable membrane is a membrane that allows some substances to pass through easily, while other substances pass through very slowly or not at all. All cell membranes, including the plasma membrane, are selectively permeable. In the exercise below, you will learn about 2 types of diffusion across selectively permeable membranes: Simple diffusion refers to diffusion of substances without the help of transport proteins. Facilitated diffusion refers to diffusion of substances with the help of transport proteins. Use the interactive exercise below to learn more about simple diffusion and facilitated diffusion. Your Turn Assume there is a higher concentration of each of the following substances in the extracellular fluid surrounding a cell than in the cell’s cytoplasm. Predict whether the substance would be more likely to enter the cell by simple diffusion or by facilitated diffusion, and explain why. Is O2 more likely to enter the cell by simple diffusion or facilitated diffusion: Explain why: Hint Check your answer. Is glucose more likely to enter the cell by simple diffusion or facilitated diffusion: Explain why: Hint Check your answer. Is Na+ more likely to enter the cell by simple diffusion or facilitated diffusion: Explain why: Hint Check your answer. Is insulin (a protein) more likely to enter the cell by simple diffusion or facilitated diffusion: Explain why: Hint Check your answer. Is estrogen (a lipid) more likely to enter the cell by simple diffusion or facilitated diffusion: Explain why: Hint Check your answer. Are hydrogen ions more likely to enter the cell by simple diffusion or facilitated diffusion: Explain why: Hint Check your answer. Dialysis tubing is composed of a selectively permeable membrane. However, its selectivit Continue reading >>

Selective Permeability & Dialysis

Selective Permeability & Dialysis

A physical process by which small sized molecules (water, glucose & maltose) are separated from large-sized molecules (starch & protein) by using a selectively permeable membrane. Experiment to show the selective permeability of visking (dialysis) tubing to starch and glucose Wash the filled visking tubing under water before immersion in the distilled water (to remove any starch and glucose on the outer surface). Test for the presence of starch and glucose (reducing sugar) in the distilled water after 1 hour. Only glucose (simple sugar) is present in the distilled water outside the visking tubing. Glucose molecules are small enough to pass through the tiny pores on the selectively permeable membrane of the visking tubing by diffusion. Starch molecules are too large so they cannot pass through the membrane. Experiment to show the action of saliva on starchy food Fill one visking tubing with starch solution. Fill the other visking tubing with starch and saliva solution. Tie the other ends of both visking tubings with threads and support them with glass rods. Wash the two visking tubings under water and then put them separately into a beaker of distilled water as shown. After 30 minutes, take samples of distilled water from the two beakers to test for starch and reducing sugar. No reducing sugar and starch are found in the distilled water surrounding the visking tubing containing only starch solution. Only reducing sugar is found in the distilled water surrounding the visking tubing containing both starch and saliva solution. Saliva contains a digestive enzyme, amylase, which can digest starch into smaller molecule - maltose. In the absence of saliva, the starch molecules are too large to pass through the visking tubing. In the presence of saliva, the large starch molecul Continue reading >>

K12.page2

K12.page2

MATERIALS NEEDED FOR ENTIRE CLASS (approximately 25): salt (NaCl) solution (approximately 1 liter) silver nitrate (Ag NO3) solution (approximately 200 milliliters) iodine (I) solution (approximately 200 millililters) Passive transport occurs when substancesdiffuse across biological membranes. Diffusion is the spontaneoustendency of molecules to spread apart and move from areas of highconcentration to low concentration. The spreading of a drop of foodcoloring in water is a good example of diffusion. The differencebetween diffusion and passive transport is that passive transportinvolves biological membranes, which can be found in virtually allliving organisms. Biological membranes are selectively permeable,which means that some substances can pass through the membrane andsome cannot. Passive transport does not require energy,distinguishing it from active transport, which does require energy(Campbell, 1990). The iodine and the silver nitrate used totest the samples from inside and outside the tubing indicate thepresence of specific molecules. Iodine turns a deep blue-black colorin the presence of starch. Silver nitrate will turn cloudy and willform a slight precipitate when it is exposed to salt. The sample fromoutside the tubing that was mixed with iodine will show no colorchange. Granted, the reddish yellow color of the iodine will give thesolution a golden tint, but no significant color change will occur.The sample from inside the tubing that was mixed with iodine willshow a noteworthy color change. The entire sample will turn a deepblue-black color, indicating the presence of starch. This color willbegin at the place where the iodine was dropped and spread throughoutthe rest of the sample. The sample taken from outside the tubing thatwas mixed with silver nitrate will Continue reading >>

Selective Permeability Of Dialysis Tubing Lab: Explained

Selective Permeability Of Dialysis Tubing Lab: Explained

Your online site for school work help and homework help. Science, English, History, Civics, Art, Business, Law, Geography, all free! Selective Permeability of Dialysis Tubing Lab: Explained Selective Permeability of Dialysis Tubing This experiment was conducted to investigate the selective permeability of dialysis tubing. The permeability of the tubing to glucose, starch and iodine (potassium iodide) was tested. The dialysis tubing was clipped to form a bag so that glucose and starch was fed into the bag through the other end, and was also clipped to avoid the seeping of the solution. Water with several drops of iodine added to it until it was visibly yellow-amber was added to a 400ml beaker. The bag was then placed in the beaker, which was stirred with a magnetic stirrer. It was left there for 30 minutes. It was seen that the color of the solution in the bag changed to blue-black color, this showed that iodine was able to pass through the membrane into the bag. The solution in the beaker became pale yellow-amber, this showed that starch didnt pass through the membrane into the beaker. To confirm the presence of glucose in the beaker and also the bag, a Benedict test was performed on the solutions including tap water (control) too. The beaker solution turned into light brown color after Benedict solution was added to it and suspended in water bath for 10 minutes. The bag solution also changed to brown color, while tap water remained blue. This experiment showed that dialysis tubing is selective in its permeability to molecules. It was permeable to glucose and iodine but not starch. PURPOSE: The purpose of the experiment was to test the permeability of dialysis tubing to glucose, starch and iodine. Living cells need to obtain nutrients from their environment and get rid Continue reading >>

Introbanner

Introbanner

1. Station 1: Identify the structureindicated by the pin matching the question number. 2. Station 1: Identify the structureindicated by the pin matching the question number. 3. Station 1: Identify the structureindicated by the pin matching the question number. 4. Station 2: Identify the organelleindicated with a pointer with the same question number. (Tues) Golgi apparatus / (Wed)Mitochondria 5. What is the function of the organelle inquestion #4? (Tues) packagingprotiens and other substances for export from the cell / (Wed) ATPproduction for cellular activities 6 & 7. The cells in your body all have thesame organelles but the number of organelles may differ depending onthe function of that tissue. For each cell type listed below name anorganelle that you are likely to find more of than the averagecell. 8. Define active and passive transport. Active transport is themovement of substances across a cell membrane through the use ofenergy and it may even be against the concentration gradient. Passive transport occurs because of a concentration gradient anddoesn't require energy. 9. Station 3: Identify the stage of mitosisthat this cell is in. (Tues)Prophase / (Wed) Anaphase 10. Describe 2 of the major events that takeplace in the stage of mitosis indicated in question #9. (Tues) Chromatin thickens into chromosomes,nuclear envelope dissolves, centrioles move to opposite poles of thecell (Wed) Spindle fibers contract pulling apart the daughterchromosomes at the centromere, daughter chromosomes migrate toopposite poles of the cell. 11. What are the two functions of mitosis? Growth and repair 12. In the osmometer experiment in lab we usedDextrose (a large sugar molecule) in the solution inside of thedialysis tubing. We used different concentrations to see how thatwould affect Continue reading >>

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