Lab 4 Assignment. Anatomy

Lab 4 Assignment Get Ready for A&P Video Tutor: Diffusion Watch the Video Tutor on Diffusion and then answer the questions below. Part A Which of the following best explains diffusion? Hint 1. Collisions Molecules are in constant motion, bumping into each other and bouncing away. ANSWER: movement of molecules from an area of high concentration to an area of low concentration movement of molecules farther away from equilibrium exchange of nonpolar molecules for polar molecules movement of molecules from where there are fewer of them to where there are more Correct By diffusion, molecules spread out to maximize their space. Part B Which of the following is most likely to move through the cell membrane by facilitated diffusion? Hint 1. Membrane structure The bulk of the cell membrane is nonpolar. 1/20 Lab 4 Assignment ANSWER: Na+ CO2 O2 small lipids Correct Ions move easily through water, which is polar, but cannot pass directly through the lipid (nonpolar) part of the cell membrane. Part C What is the basic difference between simple diffusion and facilitated diffusion across a cell membrane? Hint 1. Facilitation Facilitation refers to assistance or aid. How does this relate to some molecules passing through the cell membrane? ANSWER: Simple diffusion requires molecules to move through special doorways in the cell membrane. Simple diffusion is passive but facilitated diffusion is an active process that uses energy. In facilitated diffusion, molecules only move with the aid of a protein in the membrane. In simple diffusion, molecules move down the concentration gradient but in facilitated diffusion molecules move up the concentration gradient. Correct Facilitated diffusion allows molecules that cannot pass through the lipid component of the membrane to pass through via a more compatible protein channel or carrier. This includes ions and polar molecules. Part D Which of the following is least likely to increase the rate of diffusion? Hint 1. Collisions The more collisions that occur between molecules, the faster diffusion will occur. ANSWER: small molecule size higher concentration of molecules high temperature small concentration gradient Correct The larger the concentration gradient, the faster the rate of diffusion. Higher concentration means there are more collisions, so the molecules bounce away from each other more rapidly. Lab Manual Exercise 4 From the Book Pre-lab Quiz Question 1 2/20 Lab 4 Assignment Part A What membrane transport processes will you be examining during this laboratory exercise? ANSWER: simple diffusion and osmosis facilitated diffusion and osmosis filtration and osmosis simple diffusion and filtration simple diffusion and facilitated diffusion Correct Lab Manual Exercise 4 From the Book Pre-lab Quiz Question 2 Part A During this laboratory exercise, you will examine the effect of temperature on diffusion rate by observing the diffusion of a biological dye in what substance? ANSWER: 10% salt solution Distilled water 10% glucose solution Correct Lab Manual Exercise 4 From the Book Pre-lab Quiz Question 4 Part A In this laboratory exercise, to test the effect of membrane permeability on diffusion you will submerge a bag of dialysis tubing, filled with a 10% starch solution, in a beaker of water. ANSWER: True False Correct Lab Manual Exercise 4 Pre-lab Quiz Question 1 Part A As temperature increases, the rate of diffusion of a solute will ________. 3/20 Lab 4 Assignment ANSWER: decrease increase remain the same There is not enough information to answer the question. Correct Lab Manual Exercise 4 Pre-lab Quiz Question 4 Part A A membrane that allows some substances to travel across it while restricting the passage of others is ________. ANSWER: hypotonic impermeable freely permeable selectively permeable Correct Lab Manual Exercise 4 Pre-lab Quiz Question 6 Part A At which temperature would the rate of diffusion of dye molecules be the highest? ANSWER: 25 degrees C 10 degrees C 95 degrees C 5 degrees C Correct Lab Manual Exercise 4 Pre-lab Quiz Question 7 Part A At which temperature would the rate of diffusion of dye molecules be the lowest? ANSWER: 4/20 Lab 4 Assignment 10 degrees C 25 degrees C 95 degrees C 5 degrees C Correct Lab Manual Exercise 4 Pre-lab Quiz Question 8 Part A Which of the following substances will most freely travel across the plasma membrane? ANSWER: keratin cholesterol glucose triglyceride Correct Lab Manual Exercise 4 Pre-lab Quiz Question 9 Part A Substances tend to move from areas of ________ concentration to areas of ________ concentration. ANSWER: lower; higher higher; lower similar; higher similar; lower Correct Lab Manual Exercise 4 Pre-lab Quiz Question 10 Part A ________ transport requires the input of energy, whereas ________ transport does not. ANSWER: 5/20 Lab 4 Assignment Active; membrane Active; passive Passive; active Membrane; passive Correct Lab Manual Exercise 4 Post-lab Quiz Question 2 Part A Beaker 1 contains water at 23 degrees C. Beaker 2 contains water at 5 degrees C. Beaker 3 contains water at 95 degrees C. A drop of the same blue dye was placed in each beaker. After 10 minutes, the dye in beaker 1 moved 10 mm from the origin, whereas the dye in beakers 2 and 3 moved 2 mm and 40 mm from the origin, respectively. Which of the following statements properly explains this observation? ANSWER: The rate of diffusion does not change as temperature changes. The rate of diffusion increases as temperature decreases. The rate of diffusion decreases as temperature increases. The rate of diffusion increases as temperature increases. Correct Lab Manual Exercise 4 Post-lab Quiz Question 3 Part A Which of the following conditions must be met if diffusion across a membrane is to occur? ANSWER: A concentration gradient must be present, and the membrane must be permeable to the substance that is to be transported. The membrane must be permeable to the substance that is to be transported. A concentration gradient must be present. A concentration gradient must be present, and the membrane can't be permeable to the substance being transported. Correct Lab Manual Exercise 4 Post-lab Quiz Question 9 Part A Which of the following statements explains the observation that dye diffuses more quickly as temperature increases? 6/20 Lab 4 Assignment ANSWER: Random motion of particles increases as temperature increases. Random motion of particles decreases as temperature decreases. Random motion of particles decreases as temperature increases. Random motion of particles increases as temperature decreases. Correct Lab Manual Exercise 4 From the Book Pre-lab Quiz Question 6 Part A Match the membrane transport process with the appropriate description. Facilitated diffusion __________ ANSWER: Passive movement of substances across a membrane without the use of transport proteins Active transport of ions across a membrane Passive movement of substances across a membrane with the aid of transport proteins The transport of large particles and macromolecules into a cell The release of substances from a cell by secretory vesicles Correct Lab Manual Exercise 4 From the Book Pre-lab Quiz Question 7 Part A Match the membrane transport process with the appropriate description. Endocytosis __________ ANSWER: Active transport of ions across a membrane The transport of large particles and macromolecules into a cell Passive movement of substances across a membrane with the aid of transport proteins Passive movement of substances across a membrane without the use of transport proteins The release of substances from a cell by secretory vesicles Correct Lab Manual Exercise 4 From the Book Pre-lab Quiz Question 8 Part A Match the membrane transport process with the appropriate description. Ion pump __________ 7/20 Lab 4 Assignment ANSWER: Passive movement of substances across a membrane with the aid of transport proteins The transport of large particles and macromolecules into a cell Passive movement of substances across a membrane without the use of transport proteins The release of substances from a cell by secretory vesicles Active transport of ions across a membrane Correct Lab Manual Exercise 4 From the Book Pre-lab Quiz Question 9 Part A Match the membrane transport process with the appropriate description. Simple diffusion __________ ANSWER: Passive movement of substances across a membrane without the use of transport proteins Passive movement of substances across a membrane with the aid of transport proteins The transport of large particles and macromolecules into a cell The release of substances from a cell by secretory vesicles Active transport of ions across a membrane Correct Lab Manual Exercise 4 From the Book Pre-lab Quiz Question 10 Part A Match the membrane transport process with the appropriate description. Exocytosis __________ ANSWER: Passive movement of substances across a membrane with the aid of transport proteins Passive movement of substances across a membrane without the use of transport proteins Active transport of ions across a membrane The transport of large particles and macromolecules into a cell The release of substances from a cell by secretory vesicles Correct Lab Manual Exercise 4 Pre-lab Quiz Question 3 8/20 Lab 4 Assignment Part A When comparing the solute concentration of two solutions, the ________ solution has a higher solute concentration. ANSWER: hypertonic solvent hypotonic isotonic Correct Lab Manual Exercise 4 Pre-lab Quiz Question 5 Part A A ________ is a substance that dissolves when added to a solvent. ANSWER: compound molecule solute buffer Correct Lab Manual Exercise 4 Pre-lab Quiz Question 2 Part A When comparing the solute concentration of two solutions, the ________ solution has a lower solute concentration. ANSWER: isotonic hypertonic hypotonic solvent Correct Lab Manual Exercise 4 Post-lab Quiz Question 10 9/20 Lab 4 Assignment Part A When placed in isotonic solution, red blood cells will ________. ANSWER: swell and eventually lyse shrivel neither swell nor shrivel There is not enough information to answer the question. Correct Lab Manual Exercise 4 Post-lab Quiz Question 8 Part A Given two aqueous solutions with different concentrations of solute, separated by a selectively permeable membrane (permeable to water, but not solute), water will move from the solution with ________ solute concentration to the solution with ________ solute concentration. ANSWER: lesser; greater greater; lesser Water will not move between the two solutions. There is not enough information to answer the question. Correct Lab Manual Exercise 4 Post-lab Quiz Question 7 Part A Solution 1 has a solute concentration of 10 mOsm. Solution 2 has a solute concentration of 3 mOsm. Solution 3 has a solute concentration of 25 mOsm. Solution 4 has a solute concentration of 10 mOsm. Which of the solutions are isotonic? ANSWER: solution 2 and solution 4 solution 3 and solution 4 solution 1 and solution 4 solution 1 and solution 3 Correct 10/20