Passive Transport: Practice Problems PAP BIOLOGY

Transcription

1 Passive Transport: Practice Problems PAP BIOLOGY

2 #1 Draw a diagram where the cell has low concentration of salt molecules and the environment it is in has a high concentration of salt molecules in a water solution. Diagram which way the water molecules would move and explain why they moved that way.

3 #2 If a cell is isotonic with a 0.88% NaCl (salt) solution, how would an extracellular fluid with 1% NaCl effect the cell? Explain your answer and draw a diagram to help justify it.

4 #3 Explain why strawberries become wet after being sprinkled with water.

5 #4 You are in the hospital and need intravenous fluids. You read the label on the IV bag, which lists all of the solutes in the water. Explain why it is important for an IV solution to have salts in it. Explain what would happen if you were given pure water in an IV.

6 #5 Circle the correct term. You have a cell, with a semi permeable membrane and a 1.5% potassium concentration. You put it into a solution of 1.5% potassium. The outside solution is Hypotonic / Hypertonic / Isotonic to the cell. Water will move Into / Out of the cell and cause the cell to Decrease / Increase / Stay Constant in size.

7 #6 Circle the correct term. Last night, a skunk accidentally got locked in your friend s house. While it was in the kitchen, it heard the icemaker in the refrigerator and got scared. Instinctually, it sprayed its smelly mist over the kitchen. Within ten minutes, your friend (who was asleep in the bedroom) awoke to a terrible smell. The smell got into the bedroom by diffusing Up / Down its concentration gradient. This is an example of Passive / Active transport.

8 #7 Circle the correct term. Suppose you are trying to transport glucose across the cell membrane in red blood cells. Glucose is a large, polar molecule, so it must cross the membrane using Diffusion / Facilitated Diffusion.

9 #8 Circle the correct term. Farming that is done in very dry regions of the world leaves salts (solutes) that build up in the soil. Excess salt in the soil (the environment surrounding plant cells) is bad because it causes water to move Into / Out Of the plant cells from a High / Low water concentration inside the plant cell to a High / Low water concentration in soil.

10 #9 Below is a diagram of a cell submerged in a solution. A. What is the solution in this example hypotonic, hypertonic or isotonic? B. How do you know? C. What process is going to take place in this example? (choose one: diffusion or osmosis) D. Describe exactly what is going to happen to the cell in this example.

11 #10 A U-tube is divided into 2 halves, A and B, by a membrane which is freely permeable to water and salt, but NOT to glucose. Side A is filled with a solution of 8% salt and 2% glucose, while side B is filled with 2% salt and 8% glucose. a. In terms of glucose concentration, which side is a hypotonic solution? b. What could you say about the water concentration on side A relative to side B? c. Which molecule(s) will move across the membrane and in which net direction(s)? d. Notice that the levels of liquid in both A and B are equal. Do you think they will appear this way when the system reaches equilibrium? Explain.

12 #11 The direction in which water molecules move during osmosis depends on where the water molecules are more highly concentrated. Study the diagrams below. A. Decide whether the solution in each beaker is hypotonic, isotonic, or hypertonic in relation to the solution inside the cellulose bag, then write your answer below each beaker. B. Draw arrows to indicate the direction in which the water will move in each case.

13 #12 Explain what keeps plants cells from bursting when they are placed in a hypotonic solution.

14 #13 Explain how being placed in a hypertonic solution affects a plant cell.

15 #14 Explain what happens to the motion of molecules after equilibrium is reached during cell transport.

16 #15 Flasks X, Y, and Z contain solutions with different concentrations of the solute NaCl. Flask X has 0.5% NaCl, flask Y has 0.9% NaCl, and flask Z has 1.5% NaCl. Red blood cells (0.9% NaCl) will be placed into each flask A. Predict what will happen to the red blood cells in flask X (hint: draw out the situation). B. Predict what will happen to the red blood cells in flask Y (hint: draw out the situation). C. Predict what will happen to the red blood cells in flask Z (hint: draw out the situation).