3. How will the concentration of sucrose in water affect the amount of water that diffuses into or out of the potato cells and thereby change the mass of the potato cells? Hypotheses: 1. If the solution inside the dialysis tubing is hypertonic to the water in the beaker, then the glucose will diffuse out of the bag, and the water will diffuse into the bag, however the starch will remain in the bag. This will occur because the water and glucose are small enough to diffuse out of the pores in the dialysis bag, but the starch molecules are too large to fit through 2.
Juliana Park Mayumi Tamada CHEM 111B LAB/ M-F 1-4PM 15 August 2012 Spectroscopy Lab Introduction In this lab, the molar absorptivity of the complex FeLn2+ will be determined by using the absorbance of the complex and its concentration. The absorbance will be found by using a spectrophotometer. For the next part of the lab, the formula of the complex will be determined by also using the volume of ligand and the absorbance again. Experimental There are two different parts to the experiement. In the first part, five 100 mL flasks of 5 mL ligand solution, 5 mL 2 M sodium acetate, 4 mL 3 M NH2OH, and 1-5 mL Fe2+ solution are diluted with water.
6. Repeat step 5 four times. Data/Observations: Conclusion: Recall: We did a lab to learn about how the mass of an egg changes when it is put in different substances. Explain: We recorded the masses of two eggs every 15 minutes. One was put in water while the other was put in corn syrup.
It is important to correct the readings from the peas because the glass beads are used as a control in which no changes should occur in CO2 and oxygen levels due to their abiotic nature. 3. For both plants and animals, cellular respiration occurs not only during the daytime but also at night. However, cellular respiration cannot occur if there are not enough reactants to carry out the process. For example, because plants supply an abundant amount of oxygen to the atmosphere, it would be difficult for living cells in humans to respire if plants were ever to be demolished from Earth.
The reaction was stopped by adding 2 μL of 0.2 M EDTA at pH 8. Probe RNA was precipitated by centrifuging at 14,000 rpm at 4 degree Celsius for thirty minutes. The RNA transcripts were then analyzed by spectrometric and gel electrophoresis techniques. Spectrometric results showed an absorbance of 0.371 A at a wave length of 257 nm. We then calculated the concentration of RNA as 14.84 ng/μL, which
Cholesterol also makes the membrane less fluid by restraining the movement of phospholipids and lowers the temperature required to solidify the membrane. Complete depletion of cholesterol and sphingolipids results in cell death as their presence allows permeability to small molecules such as ions, glucose, and water. How does temperature affect lipid membrane? A membrane remains fluid as the temperature decreases, until it solidifies once it hits a critical temperature. The temperature at which a membrane solidifies depends on its fatty acid composition.
The seaweed will be cut and weighed (6 grams) and transferred into 150 mL solution. Using 40 mL of distilled water the seaweed is heated just under boiling for five minutes. After cooling, a filter will be used to remove the seaweed from the extract. The goal is to transfer 2-3 mL of filtrate into the evaporating dish. We now slowly pour the solution into a funnel with filter paper.
Then, 3.4 g of ammonium sulfate was slowly added to the supernatant 1 as it was stirred for 15 min to achieve 50% saturation (85g/L of solution). The supernatant was then centrifuged at 9000 x g and 40C for 15 min and 5 ml of the second supernatant was transferred to a conical tube. The obtained second pellet was resuspended in 4 ml of distilled water and transferred into another dialysis
BIOL1003 Methods: Lab 1: Cell Size and Structure THURSDAY Fall 2012 A Leica DME microscope was used for observations of Elodea canadensis, human cheek cell, Paramecium aurelia, Gonium sp., yeast and bacteria. A culture of the aquatic plant Elodea canadensis submerged in water was available in the lab. A single leaf was removed from a stalk and placed in a drop of distilled water on a slide. The preparation was covered with a coverslip and observed in the microscope. The preparation remained illuminated in the microscope for approximately five minutes.
Repeat steps 1-5 for trial 2. Variables and Control test: Independent Variable: Amount of each reactant poured into the test tubes Dependent Variable: Height of each solution Constant variables: Amount of time waiting for solution Data Table: Test tube # | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | Trial 1 | 0.5 cm | 1.0 cm | 1.1 cm | 1.5 cm | 1.5 cm | 1.5 cm | 1.3 cm | 1.5 cm | Trial 2 | 0.5 cm | 0.7 cm | 1.0 cm | 1.0 cm | 1.3 cm | 1.7 cm | 1.9 cm | 1.5 cm | Observation/Analysis: Solution turns yellow when a separate product is added, solid of the solution leaks down to the bottom after 20 minutes. Conclusion: The group tried to find the excess or limiting for the reaction between KI and Pb. In the end the hypothesis was supported by the data. We found that little amounts of each product led to a greater height of solids.