Dialysis Tubing Is a Selectively Permeable Membrane That Can Be

question 52

Multiple Choice

Dialysis tubing is a selectively permeable membrane that can be filled with a solution to simulate a cell.A piece of dialysis tubing has been filled with a cloudy white solution of 5 percent starch, 5 percent egg albumin (protein) ,and 5 percent glucose (a small sugar) dissolved in water to simulate a cell.This cell is weighed and then placed in a beaker of 3 percent iodine dissolved in water.When iodine and starch are mixed together,they form a bluish-black compound that is easily seen.After soaking in the yellow iodine-water solution for one hour,the cell is once again weighed.You also notice that the solution inside of the cell is now a dark blue color while the solution in the beaker is still a light yellow color from the iodine.What do you expect to happen to the weight of the cell over time and what can you deduce from the color change?

• A)The cell should lose weight over time because it is hypotonic to the beaker environment and water will enter the cell through osmosis.The color change indicates that the iodine molecules were small enough to diffuse across the membrane and react with the starch inside the cell.
• B)The cell should lose weight over time because it is hypertonic to the beaker environment and water will leave the cell through osmosis.There is nothing that the color change can tell us.
• C)The cell should gain weight over time because it is hypertonic to the beaker environment and water will enter the cell through osmosis.The color change indicates that the iodine molecules were small enough to diffuse across the membrane and react with the starch inside the cell.No color change in the beaker tells us that the starch was too large to cross the membrane from the cell and into the beaker.
• D)The cell should gain weight over time because it is isotonic to the beaker environment and water will be drawn into the cell because of the albumin.The color change does not really tell us anything about the experiment.

Discern how brand loyalty and product differentiation affect market dynamics.

Comprehend the signaling theory in the context of advertising and product quality.

Assess the economic implications of brand names on consumer choice and market efficiency.

Understand the relationship between marginal revenue and pricing within a monopoly.

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Definitions:

Human Tissue

Biological material from the human body, such as organs and cells, used in medical or scientific research.

Whistle-blower

An individual who exposes illegal, unethical, or harmful practices within an organization to the public or authorities, often at personal risk.

Consumer Product Safety Commission

A U.S. federal agency responsible for the regulation and oversight of consumer product safety standards.

Falsified Safety Reports

Incorrect or misleading safety documentation, often created to meet regulatory compliance falsely or hide deficiencies.