Name: NYS DIFFUSION LAB REVIEW Date: PACKET 1: Difusion Through a Membrane

Transcription

1 Name: NYS DIFFUSION LAB REVIEW Date: PACKET 1: Difusion Through a Membrane 1. The diagram below represents a laboratory setup used to demonstrate the movement of molecules across a selectively permeable membrane. In the diagram below, draw the 5 starch and the 12 glucose molecules to show where they would most likely be located after 15 minutes. Explain WHY you have placed the specific amount of each molecule on each side of the membrane 2. Glucose indicator was added to a beaker of an unknown liquid. Starch indicator was added to a different beaker containing the same unknown liquid. The color of the indicator solutions before they were added to the beakers and the color of the contents of the beakers after adding the indicator solution are recorded in the chart below. Which carbohydrate is present in the unknown liquid? Support your answer.

2 Base your answers to questions 3 and 4 on the diagram below and on your knowledge of biology. The diagram represents two solutions, A and B, separated by a selectively permeable membrane. 3. Which statement best describes the outcome after 20 minutes? 1) Solution A will contain approximately the same number of glucose molecules as solution B. 2) Solution A will contain all of the water molecules. 3) Solution B will remain unchanged. 4) Solution B will lose all of the glucose molecules to solution A. 4. A sample from solution A and solution B were each tested with blue-colored glucose indicator solution before the solutions were placed in the beaker. Which row represents the results? 1) 1 2) 2 3) 3 4) 4

3 5. Base your answer to the following question on the information and diagram below and on your knowledge of biology. Two models of a cell were made with dialysis tubing and placed in two beakers of fluid, A and B, each containing starch indicator solution, as represented in the diagram below. Enzyme Z was added to the artificial cell in beaker B. The solution outside each cell was tested for the presence of sugar. Initially, no sugar was present in the solution outside each cell. The results after one hour are represented below. How would the results have been different in beaker B if an enzyme that digests protein was used instead of enzyme Z?

4 Base your answers to questions 6 and 7 on the following experiment. A model of a cell is prepared and placed in a beaker of fluid as shown in the diagram below. The letters A, B, and C represent substances in the initial experimental setup. 6. Identify substance B and explain why it did not move out of the model cell. 7. Complete the table below to summarize a change in location of substance C in the experimental setup.

5 Base your answers to questions 8 and 9 on the diagram below and on your knowledge of biology. The diagram shows the changes that occurred in a beaker after 30 minutes. The beaker contained water, food coloring, and a bag made from dialysis tubing membrane. 8. Which statement best explains the changes shown? 1) Molecular movement was aided by the presence of specific carbohydrate molecules on the surface of the membrane. 2) Molecular movement was aided by the presence of specific enzyme molecules on the surface of the membrane. 3) Molecules moved across the membrane without additional energy being supplied. 4) Molecules moved across the membrane only when additional energy was supplied. 9. When the colors yellow and blue are combined, they produce a green color. Which statement most likely describes the relative sizes of the yellow and blue food-coloring molecules in the diagram? 1) The yellow food-coloring molecules are small, while the blue food-coloring molecules are large. 2) The yellow food-coloring molecules are large, while the blue food-coloring molecules are small. 3) Both the yellow food-coloring molecules and the blue food-coloring molecules are large. 4) Both the yellow food-coloring molecules and the blue food-coloring molecules are small.

6 10. The diagram below represents a laboratory setup used by a student during an investigation of diffusion. Which statement best explains why the liquid in tube A will rise over a period of time? 1) The starch concentrations are equal on both sides of the membrane. 2) The water will pass from a region of lower starch concentration to one of higher starch concentration. 3) Water and starch volumes are the same in both tubes A and B. 4) The fluids in both tubes A and B will change from a higher temperature to a lower temperature. Base your answers to questions 11 and 12 on the information below and on your knowledge of biology. Students prepared four models of cells by using dialysis tubing containing the same blue solution. Each of the model cells originally weighed 10 grams. They then placed each model cell in a beaker containing a different concentration of water. After 24 hours, they recorded the mass of the model cells as shown in the data table below. 11. What was the concentration of water in the original blue solution? State evidence in support of your answer. 12. Why did the model cell that was placed in 100% water increase in mass?

7 Base your answers to questions 13 and 14 on the information and diagram below and on your knowledge of biology. The diagram illustrates an investigation carried out in a laboratory activity on diffusion. The beaker and the artificial cell also contain water. 13. State what is observed when there is a positive test for glucose using the glucose indicator. 14. Predict what would happen over time by showing the location of molecules I, G, and S in diagram B above.

8 Answer Key NYS Diffusion Lab: Part 1 REVIEW Example: starch The solution in beaker 2 changed color Sugar would not be present. The protein enzyme would not digest the starch to sugar. 6. Example: starch -- polysaccharide -- complex carbohydrate Acceptable responses include, but are not limited to: 80%, because the model cell did not increase in mass 80%, because the model cell did not change According to the table, when the mass of the model cell is 10 grams, the concentration of water outside the model cell is 80%. This would be the same as the concentration of water inside the model cell. 12. The model cell that was placed in 100% water increased in mass because water diffused into the model cell