Osmosis in Quails' Egg

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Title: Osmosis in quails’ egg

Aim:
To observe the effect of different concentrations of sodium chloride on a de-shelled quail’s egg
To explain the effects in terms of osmosis

Research Questions:
Does the different concentrations of sodium chloride on a de-shelled quail’s egg effect the final mass of quail’s eggs that is measured by using electronic weighing balance?

Introduction:
“If a cell is to perform its functions, it must maintain a steady state in the midst of an ever-changing environment. This constancy is maintained by the regulation of movement of materials into and out of the shell. To achieve this control, cells are bounded by a delicate membrane that differentiates between different substances, slowing down the movement of some while allowing others to pass through. Since not all substances penetrate the membrane equally well, the membrane is said to be differentially permeable.

The external and internal environment of cells is an aqueous solution of dissolved inorganic and organic molecules. Movement of these molecules, both in the solution and through the cell membrane, involves a physical process called diffusion – a spontaneous process by which molecules move from a region in which they are highly concentrated to a region in which their concentration is lower.

A special kind of diffusion is the phenomenon of osmosis. Simply defined in biological systems, osmosis is the diffusion of water through a differentially permeable membrane from a region in which it is highly concentrated to a region in which its concentration is lower. More often, however, osmosis is defined in terms of the effects that solutes have on the thermodynamic activity of water (i.e., the activity of the water molecule due to the kinetic energy of motion). For example, the addition of solute to water tends to decrease the activity of the water. In other words, as more water molecules are displaced by solute molecules, the activity of the water goes down. Thus, in thermodynamic terms, water diffuses across membranes from a region in which the thermodynamic activity of water is high (low solute concentration) to one in which the thermodynamic activity is low (high solute concentration)”¹ __________________________________________________________________________ ¹ Joe Lockwood, (2012), Osmosis on Eggs: www.wasatch.edu/cms/lib/.../657/Egg_Osmosis_Lab_Packet.doc , visited August 30, 2012. Hypothesis:

When the concentration of sodium chloride on the de-shelled quails’ eggs is 0% the difference in mass of quails’ egg measured by using electronic weighing balance are the highest. When the concentration of sodium chloride on the de-shelled quails’ eggs is 30% the difference in mass of quail’s eggs measured by electronic weighing balance is the smallest. This is because the outermost layer of de-shelled quail’s egg is plasma membrane. Plasma membranes are usually permeable to water. It allows osmosis to occur. Osmosis is the passive movement of water molecules from a region of lower solute concentration to a region of higher solute concentration across a partially permeable membrane.

Variable:

Independent: Concentrations of sodium chloride on a de-shelled quail’s egg

Dependent: Different in mass of quail’s egg measured using electronic weighing balance

Control:Volume of sodium chloride solution, 70 ml.
Type of electronic weighing balance,
Type of de-shelled egg which is quail’s egg

Apparatus and Materials:

ApparatusQuantity (s)
Electronic balance 1
Beaker 500 cmᶾ1
Beaker 100 cmᶾ5
Petri dish1
Spatula 1
Measuring cylinder1
Table 1 shows: Apparatus and its quantity.
MaterialsQuantity (s)
Quail eggs 5
Sodium chloride solutions (0%, 5%, 15%, 30%, 45%)70 ml
Tissue paperSome piece
Paper towel / filter paperA piece
Hydrochloric acid 400 ml
Table 2 shows: Materials and its quantity

Procedure:

A. Preparation
5 quails’ eggs were place in a 500 ml beaker....
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