University:
Eastern Kentucky University
Course:
BIO 100 | Introductory Biology
Academic year:

2020
Views:

160

Pages:

3
Author:

sonalhava9qv

Osmosis of a potato Living Systems II MARCH 14, 2020 Lab 2 Hypothesis: The potato soaked in water will weigh more than the potatoes that were soaked in the different concentrations of salt water. Also, that the potato in the water with the higher salt concentration would weigh less than the one in the lower salt concentration water. Experiment:  Using a corer, we made a couple of potato sticks from the potatoes, then cut three pieces approximately 3cm long.  We obtained 3 small beakers and placed the potato sticks in them. We labeled the beakers with lab tape. o Beaker 1: water o Beaker 2: 0.5% salt o Beaker 3: 5% salt  We weighed (in grams) and measured each potato stick (diameter and length), and recorded the data (table below).  Into one beaker, we poured 15mL of distilled water in to cover the stick.  In the second beaker, we covered the stick with 15mL of .5% saline.  In the third beaker, we covered the stick with 15 mL of 5% saline.  After one hour, we began at 12:48pm and came back at 1:48pm, we measured the potato sticks once again.  Then after another hour (2:48pm), we measured and weighed our potato sticks again. Results Start After one Hour After 2 Hours Water .5% Saline 5% Saline Length 3cm 3cm 3cm Diameter 5.59mm 5.22mm 5.40mm Weight .936g 1.042g .891g Length 3.1cm 3.2cm 2.9cm Diameter 5.81mm 4.90mm 4.33mm Weight 1.044g 1.140g .821g Length 3.3cm 3.2cm 2.8cm Diameter 5.87cm 4.89cm 4.12cm Weight 1.111g 1.169g .798g Conclusion: After performing the experiment, I have concluded that my hypothesis was correct. The potato stick that was submerged in water grew in all three categories; weight, length, and diameter. The potato stick in .5% saline solution, shrunk slightly in diameter and weight, but grew in length. We can attest this to the fact that .5% salt in water is not a large amount. Regarding the potato stick submerged in the 5% saline solution, it shrunk in all 3 measurements. This can be explained using the principle of osmosis. Osmosis moves from an area with higher water concentration to an area with lower water concentration. Because the potato did not originally have any salt, the water went in the potato moved into the flask, because the flask water seemed to have more salt and less water than the potato. The opposite would explain what happened to the potato stick submerged in 100% water.