Research Question
What is the effect of different concentrations of sodium Chloride (NaCl) on the mass of the de-shelled quail’s eggs?
Introduction
Osmosis is an example of passive transport. Osmosis is defined as the movement of water molecules, down its concentration gradient, from an area of high water concentration (low solute concentration) to an area of lower water concentration (high solute concentration) through a selectively permeable membrane. Osmosis doesn’t need energy in form of ATP since it is passive transport and move down the concentration gradient. Cells respond to their external environment by shrinking, swelling, or staying the same based on the movement of water molecule.
The eggshell is made of calcium carbonate. When calcium carbonate is in contact with hydrochloric acid, a chemical reaction will takes place and carbon dioxide is released. This results in production of gas bubbles on the surface of the egg.
Hypothesis
The higher the concentration of sodium chloride (NaCl), the lower the mass change of the quail’s egg after being immersed in the sodium chloride solution for 24 hours. In low concentration of sodium chloride solution, the solution will be hypotonic to the egg because the concentration of solute in sodium chloride is lower than the concentration of solute in water. Water molecules move from hypotonic to hypertonic solution. Thus, water diffuses in the egg membrane by osmosis and the mass of egg increases. In high concentration of sodium chloride solution, the solution will be hypertonic to the egg because the concentration of solute in sodium chloride is higher than the concentration of solute in water. Water molecules move from hypotonic to hypertonic solution. Thus, water diffuses out from the egg membrane by osmosis and the mass of egg decrease.
Variables
Table 1 : Types of Variable Types of Variables | Methods of Controlling | Independent Variable : The concentration of sodium chloride
References: * Walpole, B, Merson-Davies, A & Dann, L 2011, Biology for the IB diploma, Cambridge University Press, United Kingdom. * 2 http://www.kidzone.ws/science/egg.htm -------------------------------------------- [ 2 ]. Walpole, B, Merson-Davies, A & Dann, L 2011, Biology for the IB diploma, Cambridge University Press, United Kingdom. [ 3 ]. http://www.kidzone.ws/science/egg.htm