Biolab 1208 Lab Report
BIOL 1208
Lab Report
Cover Sheet
I certify that the writing in this assignment is my individual work and is my sole intellectual property. It does not contain the ideas or writing of other individuals/authors.
_Alexandra DeWitt_____________ __5/1/13____________
Author Date
_10_________
Lab Section #
Increasing Sucrose Concentrations Causes the Osmotic Concentrations of Disks of Potato Tubers to Decrease
Abstract:
Introduction: The biological membranes are composed of phospholipid bilayers, each phospholipid with hydrophilic heads and hydrophobic tails, and proteins. This arrangement of the proteins and lipids produces a selectively permeable membrane. Many kinds of molecules surround or are contained within cells, but water is perhaps the single most important molecule in any living system (Hayden and McNeil 2012). Since water molecules are so small, they are constantly going into and out of the cell. Osmosis is a situation where more water molecules are moving across the membrane in one direction than the other (Hayden and McNeil 2012). During osmosis the net movement of water molecules will be from a solution that has a lower osmotic concentration to a solution that has a higher osmotic concentration. When a solution has a higher concentration of solute within the cell than out, it is called hypertonic. When a solution has a lower concentration of solute within the cell than out, it is called hypotonic. And when there are equal concentrations inside and out of the cell, it is called isotonic. The relative osmotic concentration can be determined by a change in mass of the tissue.
The purpose of this experiment is to calculate the mass/change in mass of plant tissue, in our case potato tubers. The change in mass of the potato tuber disk determines the osmotic concentration. After soaking the potato tubers in different concentrations of sucrose, then calculating the percent change in mass, we can determine the osmotic concentration. The
Lab Report
Cover Sheet
I certify that the writing in this assignment is my individual work and is my sole intellectual property. It does not contain the ideas or writing of other individuals/authors.
_Alexandra DeWitt_____________ __5/1/13____________
Author Date
_10_________
Lab Section #
Increasing Sucrose Concentrations Causes the Osmotic Concentrations of Disks of Potato Tubers to Decrease
Abstract:
Introduction: The biological membranes are composed of phospholipid bilayers, each phospholipid with hydrophilic heads and hydrophobic tails, and proteins. This arrangement of the proteins and lipids produces a selectively permeable membrane. Many kinds of molecules surround or are contained within cells, but water is perhaps the single most important molecule in any living system (Hayden and McNeil 2012). Since water molecules are so small, they are constantly going into and out of the cell. Osmosis is a situation where more water molecules are moving across the membrane in one direction than the other (Hayden and McNeil 2012). During osmosis the net movement of water molecules will be from a solution that has a lower osmotic concentration to a solution that has a higher osmotic concentration. When a solution has a higher concentration of solute within the cell than out, it is called hypertonic. When a solution has a lower concentration of solute within the cell than out, it is called hypotonic. And when there are equal concentrations inside and out of the cell, it is called isotonic. The relative osmotic concentration can be determined by a change in mass of the tissue.
The purpose of this experiment is to calculate the mass/change in mass of plant tissue, in our case potato tubers. The change in mass of the potato tuber disk determines the osmotic concentration. After soaking the potato tubers in different concentrations of sucrose, then calculating the percent change in mass, we can determine the osmotic concentration. The