Yam Core Diffusion Lab Report

The appearance after this period resulted in another color change back to white. The crucible, lid, and hydrated copper sulfate was weighed again to calculate the mass of water lost by dehydration (described in table 1.3). This was done by subtracting the final mass by the initial mass of the crucible, lid, and compound. The mass of the crucible would remain unchanged while the mass of the compound would be altered. This trial was repeated 3 times and 1 extra set of data was taken from 2 separate groups to include

First, it was hypothesized that test tube "A", the control, would not show any red concentration, test tube "B" which contains supernatant II would show the most red concentration and test tube "C" which contains sediment II would only show a little red concentration. The second hypothesis states that the raw corn kernels would have mitochondrial activity while the boiled corn kernels would not. The last hypothesis interprets that the "gunk" and sediment I will both contain starch granules. It was only expected to find mitochondrial activity in Supernatant II. Unfortunately, after performing this experiment, we were not able to support this hypothesis and come up with a conclusion.

Part A: Osmosis practical task Aim: To observe the effects of osmosis in rhubarb cells. Hypothesis: Water will be extracted out of the cells in the salt solution causing the cells to look different to the cells in the freshwater solution. Materials: Rhubarb Distilled water in a dropping bottle Salt solution in a dropping bottle Microscope, slides, and coverslips Forceps and razor blades or scalpel Paper Towel Method: Clean and dry a slide and coverslip.

For this lab I will be using water and sucrose to demonstrate the rate of osmosis. In this lab I will be exploring how temperature impacts the rate of osmosis by placing pieces of potato of equal size in solutions of different temperatures and observing the change in mass of potato after a given period of time. The change in mass will indicate the rate of osmosis.

We zeroed out the scale and weighed all four potato cores at once and recorded the mass. We then put those potato cores into the beaker of 75 mL of solution. With the potato cores in the beaker we then put a watch glass over the top of the beaker to minimize the amount of solution that evaporates. We let the potato cores sit in the solution overnight. The next day we then emptied the beaker of the solution by carefully draining the solution, while not letting the potato cores fall out.

In this practical agar jelly cubes will be used to represent a cell. AIM: To model diffusion in a practical form and investigate the effect of surface area to volume ratio. HYPOTHESIS: It is hypothesised the smaller the cube the quicker and bigger the rate of diffusion will be and with a larger cube there will be a smaller percentage of diffusion due to its bigger volume.

More specifically the aim was to investigate what effect 40% and 70% ethanol solutions had on a B. Vulgaris cell membrane and then compare them to the same test with distilled water. It was hypothesised that the ethanol solution would increase the membrane permeability. From the results the hypothesis can be supported. Cell membranes are a core aspect of understanding cells which helps to understand humans and other living creatures. Therefore the topic of cell membranes has been extensively researched, meaning that there is no limit to information and sources of information of the subject.

INTRODUCTION: In this experiment I was testing for antimicrobial sensitivity of Staphylococcus epidermidis by using the Kirby-Bauer Diffusion test. The three antibiotics utilized in this lab were: gentamicin, novobiocin, and penicillin. I determined the effectiveness of the antibiotic by observing and measuring the zone of inhibition for each antibiotic.

Diffusion and Osmosis Lab Report  By:  Jettica Williams  BIOL 1107 Lab  September 21, 2016  Prepared for Mrs. Fulford Lab Course  Page Break       The cell membrane act as a roadblock for cells.   The cell membrane has a very hectic job.   It restricts the access to what comes in and what goes out.   The bond the membrane shares with others is the idea of accountability.

By using the same mass of potato slices and putting them in different concentration of solutions for a specific amount of time will tell us how the concentration changes the mass of the potato slice. Therefore changing the rate of osmosis. Hypothesis: I predict that, if the piece of potato was put into a solution that has a high concretion of sucrose then the potato slice would lose mass as it would lose water from its cells because the water is moving out of the cell from a high concentration to a low concentration of water through a semi- permeable membrane. The cell is hypotonic and the solution is hypertonic.

Methanol, has a molecule containing CH3OH it being the smallest, ethanol having more carbons and hydrogens than Methanol comes second, CH3CH2OH, and propanol, CH3CH2CH2OH, is the largest of the three molecules. Aim: The aim of this experiment is to see the effects of different alcohols and concentrations on the biological membrane of the beetroot. Research Question: How do different alcohols and concentrations affect the biological membrane of a beetroot? Hypothesis: As the alcohols increase in toxicity and concentration, the damaging and breaking down of the membrane will increase leading to more red pigment being released into the solution causing the absorption of the solute to increase.

The hypothesis we came up with for this project was that in the distilled water there wouldn't be no change in the potato, we wouldn’t see a gain or loss with the water sitting in the beaker. The beaker with the 30% Sucrose and Distilled water we predicted that there was going to be weight gain to the potato. And for the distilled water with the 30% sucrose and we predicted weight loss. But the results came out to be the first bag content being isotonic the second bag came out to be hypotonic and lastly the result came out to be

In this experiment, the amount of water lost in the 0.99 gram sample of hydrated salt was 0.35 grams, meaning that 35.4% of the salt’s mass was water. The unknown salt’s percent water is closest to that of Copper (II) Sulfate Pentahydrate, or CuSO4 ⋅ 5H2O. The percent error from the accepted percent water in CuSO4 ⋅ 5H2O is 1.67%, since the calculated value came out to be 0.6 less than the accepted value of 36.0%.This lab may have had some issues or sources of error, including the possibility of insufficient heating, meaning that some water may not have evaporated, that the scale was uncalibrated, or that the evaporating dish was still hot while being measured. This would have resulted in convection currents pushing up on the plate and making it seem lighter by lifting it up

Chemistry IA Background information: Introduction: Electrolysis it’s a chemical process that when you pass an electric current into a solution or a liquid that contains ions to separate substances back to their original form. The main components that are required for electrolysis to take a place are:  Electrolyte: it’s a substance that when dissolved in water it ionize and then it will contain free moving ions and without these moving ions the process of electrolysis won’t take place.  Direct current (DC): This current provides the energy needed to discharge the ions in the electrolyte  Electrodes: it’s an object that conducts electricity and it’s used in electrolysis as a bridge between the solution and power supply. A great example

Biology Design Practical Joshua Edwards What are effects of the volume of a potato and the amount of weight it loses when placed in salt solution? Introduction This design practical uses a potato’s surface area to volume ratio to see what affects it has on osmosis in different concentrations. Osmosis is the movement of water molecules through a cell membrane into an area of a higher solute concentration. The movement goes the way of the solvent with more solute because the lower solute concentration is drifting through balancing the ratio of solute per solvent (En.wikipedia.org, 2018).