Membrane Physiology Essay, Research Paper

IntroductionThe cell membrane is a unstable construction that is made up of phospholipids and proteins. Its chief map is to let osmosis and diffusion to happen in a cell. It protects a cell from taking in molecules that are excessively big and other chemicals that are non permeable without energy being used. The cell membrane is considered to be selectively permeable because it does non let the non-fat soluble chemicals and the larger molecules in, but it does let fat soluble chemicals and little molecules to go through into the cell. In order for the larger molecules and non-fat chemicals to come in the cell protein channels and energy are needed. In this lab you will see the cell membrane working. The experiment will demo the Osmosis of H2O and a sucrose solution. Osmosis is net motion of H2O molecules from a high to low concentration until equilibrium is reached. In other words, Osmosis is the diffusion of H2O. Through the diffusion of H2O Isotonic solutions may happen. This is where both sides of the membrane have an equal sum of H2O. There may besides be a Hypertonic solution. That is where the membrane has more H2O and the concentration will travel down a gradient doing the membrane to shrivel. Another solution that may happen is a Hypotonic solution. This type of solution allows the H2O molecules to go through through the cell membrane into the solution doing the cell to increase in size. Diffusion of dye in agar and H2O will be studied in this lab. Diffusion is the motion of a concentration from a high gradient to a lower gradient until country is at same degree. We will besides analyze the permeableness of the cell membrane when different solutions are used inside and outside of the cell. In this lab, we will detect the alterations taking topographic point during the diffusion of dye through agar gel and through H2O. We will find what type of solution is formed when puting the mock cell membrane in different degrees of solution. We will cipher the rate at which the dye diffused and plot the findings in a chart to demo the different rates each cell changed.

Hypothesis

In Part A of the lab the cell membrane of bags 2 through 4 will derive mass because of the usage of sucrose solution in the cell. The H2O will travel through the dialysis tubing to organize equilibrium between the membrane and outer concentration. Bag 5 will be a Hypertonic solution, the H2O is at a high gradient and the solution environing the cell is at a low concentration gradient, doing the bag to shrivel. Bag 1 will hold an Isotonic solution. In Part B of the lab, the K permanganate will spread faster in H2O so in the agar gel. In Part C of the lab, the solutions in the bag and the solutions around the bag will be the same after the testing is done. Starch, chloride, protein, and sulfate ions will be found in both countries tested.

Materials and Methods

See the affiliated sheets for stuffs and methods used.

Consequences

Part A: In bag 1 the mass changed 1/10 of a gm. In bag 2 the mass changed 4.4 gms. In bag 3 the mass changed 6.3 gms. In bag 4 the mass changed 8.3 gms, and in bag 5 the mass changed to a negative 6.0 gms.

Part B: The methylene blue diffused through the agar gel a sum of 4.5 millimeters and the K permanganate diffused 10.5 millimeter. The K permanganate diffused through the H2O a sum of 15 millimeter.

Part C: The solutions in the bag contained amylum, which caused the solution to turn black. Sulfate ions an

vitamin D proteins were non found. Chloride ions were found in the solution, the solution turned into an orange-milky colour. The solutions in the beaker contained no amylum. There were sulfate ions found, which caused the solution to hold white atoms drifting in it. Chloride was found in the solution, the solution turned into a xanthous colour. The beaker besides contained proteins, the colour of the solution turned to a violet colour.

Discussion and Decision

The findings for Part A backed up my hypothesis. Bags 2 through 4 did hold a Hypotonic solution. The 5th bag & # 8217 ; s solution was Hypertonic and bag 1 involved an Isotonic solution. The relationship between sucrose solution and osmosis is that the higher the sucrose solution the faster osmosis occurs. The H2O molecules are traveling faster through the sucrose solution so that equilibrium is met in the cell and environing solution. The H2O for bags 2 through 4 are traveling into the dialysis tube, that is why the dialysis tube expanded and had a Hypotonic solution. For bag 5 the H2O was traveling out of the dialysis tubing into the sucrose solution which is why there was a Hypertonic solution. The chart showed that the mass did increase steadily for bags 2 through 4 and the mass decreased steadily for bag 5. Bag 1 had a little lessening, which could be an mistake in reading the ternary beam graduated table used to happen the mass of the bag. Puting an ameba into a jar of H2O for a certain clip could do the ameba to split. The ameba contains 10 % solutes, which would do the H2O to flux into the cell to make equilibrium. This would be a Hypertonic solution. The Hypothesis for Part B was found to be true. The K permanganate diffused faster in H2O so in the agar gel. The agar gel has a thicker concentration doing the motion of the dye slower than the motion of dye through the H2O. The affiliated sheet will demo the consequences of the trials done in Part B to back up the Hypothesis made. The inquiries refering Part B are besides included on the affiliated sheet. In Part C of the lab, my hypothesis did non keep up. There was a discrepancy in which solutions were found in the beaker and in the bag. The findings in this experiment are outlined on the affiliated sheet. I believe the differences were caused by selective belongingss that the cell membrane has. The dialysis tubing working like the cell membrane would let the Na molecules to be pushed out of the cell and back in to the cell with the fond regard of other molecules. That is why sodium sulphate was non found in the bag but Na chloride was. The bag pushed out the sulphate molecules through active conveyance and brought in the chloride molecules besides through active conveyance. The amylum molecules must play an of import axial rotation in the cell and the molecules were non allowed to go through through the cell membrane. The protein molecules were non allowed to go through through the cell membrane because they perchance could non-fat solubles or the atoms were excessively large to go through through. They would necessitate energy to go through through the cell membrane and protein channels that were non present in the dialysis tube. The experiments done helped explicate what was being discussed in the reading assignments and gave me a better apprehension of how cells work. The work cells do maintain our organic structures healthy and keep a balance in our organic structures to assist contend against infections. The workss, animate beings, and all other life beings would non be able to last if the cells did non follow the simple regulations of which molecules are needed to keep equilibrium in all living things.