In experiment 4, why was the final water displacement higher than the initial, r
ID: 67236 • Letter: I
Question
In experiment 4, why was the final water displacement higher than the initial, regardless of the type of potato?
Water flowed out of the potatoes due to osmosis
Water flowed into the potatoes due to osmosis
The tonicity of the potatoes' cells limited water movement
The cells of the potatoes' lysed and collapsed, taking up less space
Water flowed out of the potatoes due to osmosis
Water flowed into the potatoes due to osmosis
The tonicity of the potatoes' cells limited water movement
The cells of the potatoes' lysed and collapsed, taking up less space
Experiment 2: Tonicity and the Plant Cell Plant cells are able to generate osmotic pressure while other cells cannot. This is due to specialized plant structures such as the cell wall which prevent lysis caused by osmosis. By taking advantage of this system, you will be able to look at the effects of tonicity in a biological system. Knife for cutting Ruler Paper towel* Materials 20% sodium chloride (NaCl) solution Several types of potatoes (e.g. russet, s (e.g. russet, ach* Watch* Yukon, yams) 2 Plastic test tubes 100 mL Graduated cylinder Water 2 Pipettes Permanent marker You must provide 7: Osmosis Procedure 1. Label two test tubes (A and B) for each type of potato you will be testing. Be sure to write the type of potato on the tube as well. Fill in the types of potato used in this experiment in the "Type of Potato" column of Table 3. 2. Carefully cut two strips of each type of potato on a cutting board. The strips should be as close to 10 cm long and 1 cm wide as you can cut them so they fit into the test tube. Note: In the next step, you will account for any variability by measuring the volume of water displaced when submerged into a beaker containing a known volume of water 3. Place one strip of the first type of po- Fill the 100 mL graduated cylinder with 50 mL of water. tato (Sample A) into the graduated cylinder and record the amount of water it displaced in the "Initial Displacement column of Table 3 in the row corresponding with the sample tested. Note: Displacement is a measurement of change and is calculated by subtracting the original volume (50ml) from the final volume that you read after the potato is added to the 50 mL of water. (e.g. 57 mL-50 mL 7 mL) 4. Remove Sample A from the graduated cylinder and, if any water was lost, fill the graduated cylinder up again with 50 mL of water. Place Sample A into the corresponding test tube.Explanation / Answer
Water flowed out of the potatoes due to osmosis.
[The water tends to move towards higher concentrations of dissolved chemicals. That means that if the water outside the cell is saltier than the water inside, water will move from the inside of the cell to the outside. In our case outside concentration is 20 % sodium chloride which is much higher than normal physiological concentration]