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. If a solution is very hypertonic, then the most amount of water will diffuse across the semi-permeable membrane into the dialysis tubing. This occurs because the higher concentration of solute, the more water it takes to reach equilibrium, thus, the faster rate of osmosis. 3. If we place the potato in a sucrose solution with a similar solute concentration as a potato, then the least amount of water will diffuse into or out of the potato cells.
Water continually flows in and out to keep concentration even. Hypertonic Solution: Concentration of the cell is less than outside of the cell. Water moves out of the cell to try to even out the concentration. In this lab we are using four different simulated cells with three different solutions to simulate three differing tonicities. The first simulated cell will be 1% sucrose solution placed into a 1% sucrose solution.
Microbiology lab : task 1 Western Governors University Microbiology lab : task 1 The Methyl Red Test is used to identify bacteria according to their pattern of glucose metabolism. Phosphate buffers, glucose, and peptone make up the Methyl Red broth. Bacteria that produce mixed acids decrease the Ph of the broth. Non-acid end product producing bacteria do not decrease the Ph. Methyl Red turns red for a PH that is lower than 4.4 and it turns orange for a Ph between 4.4 and 6.0.
If there are higher levels of potassium, then the resting membrane potential will be less than normal and an action potential will be not likely with the same amount stimulation. More voltage is needed. • Explain how hypokalemia will initially affect the resting membrane potential and the generation of an action potential. The resting membrane potential is based on the polarization of the cell. If there are lower levels of potassium, then the resting membrane potential will be higher than normal and an action potential will be more likely with less stimulation.
BE READY WITH THE STOPWATCH. Record the time in the data table. Room Temperature Water: Fill beaker with 80mL of water. Use thermometer to record the temperature Drop Alka-Seltzer tablet in water. Measure the time it takes to completely dissolve.
When the average heart rate from the Control group, (151), is compared against the 3 average heart rates recorded from the three strengths of alcohol, (133, 109, 109), I interpreted that the heart rate is reduced at all alcohol strengths. My hypothesis for the Caffeine portion of the experiment was that at the introduction of caffeine to the water flea, as well as each stronger level of caffeine to its system, the water fleas heart rate would increase. When the average heart rate from the Control group, (176), is compared against the 3 average heart rates recorded from the three strengths of caffeine, (175, 173, 176), I interpreted that the heart rate is similar to both the control test, as well as with all alcohol strengths. I did not expect those results; I anticipated a higher heart rate. Were I to conduct this project again, I would find a more accurate way to measure the heartbeats, wait longer between applications of both alcohol and caffeine and wait longer after each application of alcohol or caffeine for it to take effect in the water fleas system.
Hypotonic means less salute and more water. For this lab, we can apply these principles to plant cells. The plant cells have a semi permeable membrane so they can experience osmosis and diffusion as discussed earlier. When it comes to the potato cells, added with NaCl (salt) it will experience a reaction changing the form of the cells. The hypothesis of this experiment goes as follows, If we place potato cells in a salt solution, then the cells will shrink.
The test was completed 27 times and each time the hotter tap water froze before the cooler water. Experimental design: Items used include: · 2 identical ceramic bowls that have been sitting at room temperature · 8 ounces of distilled water (water that has been heated and vaporized in order to remove contaminants and other elements) · A thermometer that reads between 0-220 degrees Fahrenheit (I will use a Taylor Classic Instant-Read Pocket thermometer) · A refrigerator freezer to freeze
This is called plasmolysis. Introduction The aim of this experiment is to investigate osmosis and plasmolysis in potato (Solanum tuberosum) cells when immersed in different solution types. The types of solutions that will be used in this experiment are distilled water, 0.5 NaCl and 1.0 NaCl. Osmosis is the diffusion of water across a permeable membrane from a region of high water concentration to low water concentration until even. The semi permeable membrane only allows small molecules such as oxygen, carbon dioxide, water and glucose to pass through, yet it does not allow larger molecules such as starch and proteins.
If the area around a cell has a higher water concentration it will gain water by osmosis. This is because the water molecules surrounding the potato cell are able to pass freely across the cell membrane in both directions; therefore more water will enter the potato than will leave it so it will swell up. Furthermore, if the area around the potato’s cells has a lower concentration of water than the cell will loose water by osmosis due to more water diffusing out through the partially permeable membrane than entering the cell, this will lead to a reduction in the size of the cell. When the concentration of water molecules in the potato is near equal to that of the area around it, the rate of osmosis will decline and the cell will stay the same size, as there is an equal amount of water entering the cell than there is leaving it. Below is a drawn diagram showing the process of osmosis.