1 / 17

What Is The Connection?

What Is The Connection?. A conceptual problem…. Q = How do cells feed and excrete?. A = Via their cell membranes So therefore, shouldn’t cells require MORE surface area?. Lab: Assessing the Rate of Cellular Diffusion v. Differing Surface Area to Volume Ratios.

wren
Download Presentation

What Is The Connection?

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. What Is The Connection?

  2. A conceptual problem… • Q = How do cells feed and excrete? • A = Via their cell membranes • So therefore, shouldn’t cells require MORE surface area?

  3. Lab: Assessing the Rate of Cellular Diffusion v. Differing Surface Area to Volume Ratios • Purpose: To determine how the size of a cell is related to its ability to perform diffusion • Method: Measurement of conductivity of the solution. The greater the rate of diffusion, the greater the rate of change in conductivity (as measured in µS/cm/sec)

  4. Calculating S.A.: Vol Ratios • From block of sodium-infused agar, cut 3 2x2x2 blocks • Cut 2nd block into eight cubes • Cut 3rd block into 64 cubes • Calculate cumulative S.A.: Vol. ratios for each set of cubes

  5. Collecting the data • Place the first 2cm3 cube into 300 mL of tap water • Immerse the conductivity probe into the tap water bath • Collect data, while STIRRING CONSTANTLY for 300 seconds • Determine the slope in µS/cm/sec

  6. Processing/Interpreting The Data • Graph the rate (y-axis) vs. ratio of S.A.: Vol. (x-axis) • Answer the analysis questions in your lab notebook

More Related