Preparation for the lab included making 1 molar solutions of each sucrose, NaCl, dextrose, and ovalbumin; filling each semipermeable tube with 20 mL of the solution; taking the initial weight of the tubes and submerging each tube in a beaker of the corresponding solution. For example, when the cube doubles from a length of 1 cm to a length of 2 cm, the surface area increase by a factor of four, going from 6 cm 2 1 cm x 1 cm x 6 sides to 24 cm 2 2 cm x 2 cm x 6 sides. Variables: The independent variables are the dimensions of surface area to volume ratio of the agar cube. This experiment consists of using agar mixed with an indicator that changes color when places in a basic solution. Conclusion Questions: 1 In terms of maximizing diffusion, what was the most effective size cube that you tested? I concluded that diffusion varies with time and solutions. Strain out the cabbage, and use the remaining purple water to mix with the agar powder. Immerse your 3 cubes in the sodium hydroxide solution, noting the time.
At about 33% of sucrose, the potato would have been isotonic to the solution. Which of these cubes is going to be the most effective at maximizing diffusion, how do you know this? These systems, such as the cardiovascular, digestive and respiratory systems, perform life processes necessary for survival. If you're using phenolphthalein, you should have two sets of pink cubes. Record any observations in your lab book. We made 3 cubes out of each mold to have multiple trials.
Data: Cube color Cube Size cm Volume not Cube diffused Volume cm³ cm³ Volume % Diffusion diffused cm³ Surface area cm² Ratio Clear Clear Clear Pink Pink Pink 3 2 1 3 2 1 18 8 1 18 8 1 16. A hypertonic solution is a solution in which the solute concentration is higher outside of the cell; therefore, water will flow to the external environment, causing the cell to shrink. The quantitative results I base my hypothesis on was the differential in milliseconds of a faster reaction time between the control group and the experimental group. Upon investigation, our hypothesis was, sadly, proven to be correct. They must regulate moving necessary materials in and out of the cell in order to maintain homeostasis. Solutions in the bag that consisted of more water lost weight, while solutions in the beaker which contained more water gained weight. Then, we microwaved the agar and water mixture in durations of 45 seconds each, watching the beaker carefully until it was clear, and a bubbling liquid.
My hypothesis is that the glucose and sucrose will be hypertonic to other solutions due to its concentration of water. Cells are able to move through selective permeable cellular membranes. Also, multicellular organisms have separate organ systems to perform specific tasks. Diffusion is known as the simplest form of movement, where solutes spread from a high concentration area to a low concentration. In this experiment, I tested the diffusion in a cell- in this case, the dialysis tube. There are a number of methods that would have optimized the results of the experiment to come to a more definite conclusion. With osmosis, water can move throughout the membranes of a cell, down its concentration gradient.
Among these errors, and the data collected, it is safe to conclude that our hypothesis was correct but could have been better represented without these flaws. The potato was then pierced 4 more times from each of the four concentrations, to have a total of 5 trials. One possible answer can be found in the relationship between cell size and the diffusion of substances across the cell membrane. To find the volume, multiply the length of the cube by its width by its height. Research Question: How does the size of the cell affect its efficiency in exchanging substances through several ways, like diffusion? This will give you the area of one face of the cube.
Some fungi produce fruiting bodies which bear spores. Carefully return all of the treated cubes to the vinegar. Purpose:Determine how surface area and volume relate to one another and how the rate of diffusion varies with the ratio of surface area to volume. There are a few types of diffusion. This solution was an error because it should have continued the line and digressed but instead, it increased more that the solution of 75% sucrose sand 25% water. A series of membrane-bound structures continuous with the plasma membrane, such as the endoplasmic reticulum, provide additional surface area inside the cell, allowing sufficient transport to occur. It is important to make each tube in a medium between flimsy and firm.
Potatoes, sweet potatoes, and yams are ideal starches to use in this lab. The sizes of the cubes were not exact as mentioned Ex: 1 cm3 is not exact and as a result the results obtained may not be very accurate. When cutting, a more precise instrument must be used. The placement of the agar in the beaker could be an error because some cubes may be more exposed to the dye than cubes at the edge of the beaker. To determine the volume of this inner cube, measure the length of this inner cube and multiply it by the width and height. In order to make results to this lab more precise, it is ideal to use cubes instead of blocks.
As the size of an object increases, the volume also increases, but by more than you might think. Diffusion Introduction Diffusion is the net movement of ions or molecules from a region of high concentration to a region of low along the concentration gradient until equilibrium has been reached. By dividing this number by the original volume and multiplying by 100%, you can determine the percentage penetration for each cube. Subject 2 of the control group had a faster a reaction time of 8 seconds with 166. The smallest cube was the most effective at maximizing diffusion because it has the smallest volume, so the diffusion can occur all the way through the cube. Each mold was set to dry overnight. Interaction between selectively permeable membranes, water, and solutes play a major role in the functions of cells and organisms.
Keep your eye on it as it can boil over very easily! The goal of this lab was too see what surface area to volume ratio of the cubes would yield the greatest percentage of diffusion. The movement of the solution was from the area of high concentration to the area of low concentration. When using diffusion and osmosis you are trying to separate different solute concentrations on either side of the membrane. Diffusion affects smaller cells more with the same time period, compared to a cell of more mass. The rate of diffusion depends on the dimensions of each cell. Agar is similar to gelatin and must be made perfectly.