Osmosis Lab Report Essay

Purpose: The purpose of this lab is to familiarize you with osmosis and, specifically, what happens to cells when they are exposed to solutions of differing tonicities.

The lab for this paper was conducted for the topic of osmosis, the movement of water from high to low concentration. Five artificial cells were created, each being filled with different concentrated solutions of sucrose. These artificial cells were placed in hypertonic, hypotonic, or isotonic solutions for a period of 90 min. Over time, the rate of osmosis was measured by calculating the weight of each artificial cell on given intervals (every 10 minutes). The resulting weights were recorded and the data was graphed. We then could draw conclusions on the lab.

Osmosis is the diffusion of water across a membrane to create an equilibrium between the levels of concentration of a solute both inside and outside the cell. In this case the solute will be sugar as the potato core will be immersed in sucrose solution.

The hypothesis states that if the solution is hypotonic the results will decrease, if the solution is hypertonic the results will increase and if the solution is isotonic the solution will vary and or remain constant. In order to test the predictions of the hypotonic, hypertonic, and isotonic hypothesis for the solution  made during the study,  four samples of sucrose were taken and placed into two different beakers each containing a different concentration. Then dialysis tubing A was placed into beaker 1 with B, C, and D placed into beaker 2 for 45 minutes and weighted at 15 minute intervals. My finding in the study was that each of the four samples changed from their initial weight and for the most part accurately proved the hypothesis.

The reasoning behind this experiment is the examine whether the rate of osmosis is changed due to a change in temperature. It was hypothesized that the rate of osmosis will increase as the temperature of the sucrose is increased. The rate of osmosis was tested by using the different jars full of different temperate water and testing how high the water rose on an osmometer over a span of 20 minutes. An osmometer is a tool used to measure rates of osmosis. The different temperatures tested on a sucrose solution were 5 degrees Celsius, 20 degrees Celsius, and 37 degrees Celsius. Rates of osmosis were higher in the hot water than in the cold water and control. The results showed that the rate of osmosis increased as the temperature increased, henceforth the hypothesis was supported. In conclusion, the experiment showed how changes in temperature affect the rate of osmosis.

Conversely, animal cells thrive best in an isotonic environment, where there is no net change in their concentration. During the osmosis portion of the lab we created four dialysis bags of varying concentrations and place the bags in solutions of either 30% sucrose or reverse osmosis water (RO water). Two bags held RO water and the two other bags held either a 15% or 30% sucrose solution. We then observed and recorded the mass of the bags over the course of an hour to determine in which direction the osmosis occurred for each bag and at what rate.

Diffusion is the transfer of molecules from an area that has a higher concentration to an area that has a lower concentration. Osmosis is the diffusion of water. The purpose of this experiment was to study the process of osmosis. In order to test osmosis, eggs that had been soaking in vinegar were taken and placed in four beakers of solution with different levels of glucose. Using this experiment we were able to determine the rate of osmosis of different solutions, with various amounts of glucose, through eggs. In the results of this lab it was found that the eggs were either hypertonic or hypotonic and that the

Osmosis is the diffusion within water in which a semi-permeable membrane allows for a higher concentration solution to diffuse across said membrane into the lower concentration solution. Osmosis drives most biological processes allowing for equilibrium to be met and the transportation of molecules to occur (Nave, n.d.). However, larger biological molecules cannot pass through semipermeable membranes such as sucrose and starch (“GCSE Biology…”, n.d.). Within this experiment, the percent change of weight must be calculated to be able to quantitatively define the concentration movement of the molecules across the gradient.

The objective of this lab was to learn how to identify diffusion and osmosis, through selectively permeable membranes. Diffusion is the process in which particles move from an area of high concentration to an area of low concentration. When water enters or leaves a cell, it is called osmosis, which is the same process as diffusion, but solely focused on water. Certain membranes allow only particular chemicals to pass. These are called selectively permeable membranes.

INTRODUCTION: Osmosis is a type of diffusion where high concentrated water molecules move to lower concentrated water molecules through a selectively permeable membrane. Different concentrations affect the rate of osmosis. By increasing the amount of solvent in a solution, there will be lower water potential. If the water molecules inside of a cell has a higher concentration than outside, the water molecules would end up moving out of the cell.

The purpose of this investigation lab is to observe osmosis of water into a cell, and also how. The goal of the experiment is to prove that a solution in an area of high concentration will move to an area of low concentration. In this experiment, we used sheep blood, 0.9% NaCl, 10% NaCl, and dH2O water to see what will cause when we add this to the cell. We will then record the rate of diffusion by measuring how did the blood flow into each solution and recording them. First, we placed with the wooden applicator stick, then dip the end into the blood and place tiny drop in the slide to observe what it will do.

One experiment was conducted for this lab report on osmosis and diffusion and how the concentrations effect a cell. The lab consisted of weighing 4 potato cylinders and putting them into 4 cups with different levels of sucrose solution. After incubating for two hours the potatoes were weighed again and the data was collected. The results showed two increasing, one staying the same, and one decreasing in mass. Osmosis is when water moves across cell membranes until both sides are balanced (Campbell 107).

The hypothesis that was stated prior to the lab was that the potato was going to be isotonic with the 0.1 solution. As seen from the data, the potato was isotonic with the 0.2 solution. This is because there was the least amount of weight change showing that the concentrations were isotonic and osmosis did not occur as much. As oppose to the concentration of 0.6 which caused weight percent to drastically decrease. This means that the two solutions were not equal and osmosis occurred and changed the initial weight of the potato.

Lab Objective: The purpose of this experiment is to test the membrane dynamics of different solutes when placed in unique solutions and the effect this has on diffusion rate, osmosis, and membrane permeability.

Cells are important because they carry out all activities necessary for life. Cell structure can be examined and observed under a light microscope. The cell membrane is a critical component of the cell because it controls which materials pass through the cell. Osmosis, the movement of free water across the cell membrane, is demonstrated by examining the movement of material across the cell membrane of potato tissues. Potato tissues were put into various concentrations of NaCl to examine the effect of concentration on the potato tissues. Our hypothesis is if there is a higher concentration of NaCl, then the potato tissues will decrease in weight. In addition, the effect of concentration gradient and temperature on the rate of osmosis in an artificial system were investigated by using dialysis tubing. In this lab, the investigated variables were the change in temperature between 15°C and 55°C and the change in concentration of the NaCl solution. Our hypothesis is if there is a greater concentration gradient, then it will have a greater effect on the increased rate of osmosis compared to temperature. Determined was that as temperature and concentration gradient increased in solutions, the rate