Bi1X_Week6_GrowthCurves_v2_2011 - Bi 1X, Spring 2011 Week 6...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Bi 1X, Spring 2011 Week 6 Session 1: Growth Curves Background: Cell Growth and Spectroscopy While there are a multitude of important time scales in biology, arguably one of the most important is concerned with the rate of cell division. In the bacteria E. coli , rates of cell division are closely linked with evolutionary fitness and hence our basic understanding of natural selection. To better understand the concepts involved in cell division, we will measure the bulk growth rate of E. coli in media with different amounts of antibiotic. We measure cell growth using spectroscopy and optical density as outlined in the following section. The included formulas will prove useful in analyzing your spectroscopic data. Beer’s Law and Optical Density It is often extremely useful to know the concentration of cells in a liquid culture, and can be used in various kinetic measurements of fitness and protein production. Light scattering is the primary method by which we measure cell density. In the following section, we will discuss the basic physical concepts that allow determination of concentration as well as the formulas that relate optical properties to concentration. The basic physics are as follows: 1. Light, with a wavelength comparable to the size of the object being measured (600 nm), enters the sample at an initial intensity (
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This document was uploaded on 01/03/2012.

Page1 / 3

Bi1X_Week6_GrowthCurves_v2_2011 - Bi 1X, Spring 2011 Week 6...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online