Assignment 5 Overview

20.309: Biological Instrumentation and Measurement

Assignment details

This assignment has 2 parts:

Part 1: Implementing difference tracking and measuring the stability of your microscope;
Part 2: Live cell particle tracking of endocytosed beads.

Submit your work in on Stellar in a single PDF file with the naming convention <Lastname><Firstname>Assignment5.pdf.

Here is a checklist of all things you have to turn in: For Part 1: For a slide of fixed beads:

Plot the MSD versus time interval of
- the raw trajectories,
- the sum trajectories, and
- the difference trajectories.

For Part 2:

Procedure
- Document the samples you prepared and used and how you captured images (camera settings including frame acquisition rate, number of frames, number of particles in the region of interest, choice of sample plane, etc)
Data
- Include a snapshot of the 0.84 μm fluorescent beads monitored.
- Plot two or more example bead trajectories for each of the samples. (Hint: If you subtract the initial position from each trajectory, then you can plot multiple trajectories on a single set of axes.)
Analysis and Results
- Plot the average MSD (from the difference trajectories) for untreated and cytochalasin D treated cells on a single set of log-log axes.
Discussion
- What kind of motion do you see described by your MSD vs τ results?
- What differences do you see between the untreated and Cyto D treated MSD curves?
- Please suggest an interpretation of the behavior of your cells based on your data.
- Include a discussion of your error sources.