MOSIS TENTI IN TATOE PERIM T Rebecca on Osmosis Potential In Potatoes
Osmosis Potential In Potatoes Investigating the water potential of a potato cell The aim of this investigation was to investigate the water potential of a potato cell in six different solutions. Research question: Cube’s cut from inside of potato is submerged within different sucrose concentrated solutions. Will the size of the cube decrease or increase with a higher sucrose concentration? (athenology.com) Introduction “Water potential is the potential energy of water in a system compared to pure water, when both temperature and pressure are kept the same. It can also be described as a measure of how freely water molecules can move in a particular environment or system.” (biologydictionary.net, Ref.2) When the potato is in the test tube along-side the solution, the solution enters the potato slice through osmosis. The potato cell contains pores which allows the solution to enter, we call this aquaporin. “Osmosis is the spontaneous net movement of solvent molecules through a selectively permeable membrane into a region of higher solute concentration, in the direction that tends to equalize the solute concentrations on the two sides.” (en.wikipedia.org, Ref.3) Aquaporin is “any one of group of proteins in cell membranes that allow the passage of water across the membrane” (thefreedictionary.com, Ref.4) Cell Membrane Structure Above Shows A Diagram Of A Fluid Mosaic Model Fig.1 “The cell membrane (plasma membrane) is a thin semi-permeable membrane that surrounds the cytoplasm of the cell.” (thoughtco.com, Ref 5) The function of the cell membrane Is that it acts as a barrier between the inside and outside of the cell, it also chooses which materials enter or leave the cell. The cell membrane has a phospholipid bilayer which allows for cellular shape changes. There are two parts of a phospholipid; 2
Osmosis Potential In Potatoes hydrophilic head and hydrophobic tails. The phospholipid head also known as the hydrophilic head “ contains a negatively charged phosphate group and glycerol” (en.wikipedia.org, Ref 6) The phospholipid tails also known as the hydrophobic tail s “usually consist of 2 long fatty acid chains; they are hydrophobic and avoid interactions with water. When placed in aqueous solutions, phospholipids are driven by hydrophobic interactions that result in the fatty acid tails aggregating to minimize interactions with water molecules. These specific properties allow phospholipids to play an important role in the phospholipid bilayer .” (en.wikipedia.org) Integral Protein cross all the way through the membrane bilayer, they are generally used for anything that requires transmission across the membrane, such as receptor signals or small molecule transport.