Lecture 6 - BME 418, Quantitative Cell Biology Alan J. Hunt...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
BME 418, Quantitative Cell Biology Alan J. Hunt Lecture #6: Momentum and Reynolds #, Introduction to Eukaryotic Cells, intracellular organelles. Before we leave the prokaryotes and begin discussion of eukaryotes, we'll touch on one more issue concerning bacterial motility: the effect of momentum. It's very informative to consider how far a bacterium will coast after it stops swimming.
Background image of page 1

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

View Full DocumentRight Arrow Icon
BME 418, Quantitative Cell Biology Alan J. Hunt A bacterium coasts for a distance much shorter than the diameter of a hydrogen atom! So, for a bacterium, it's as if acceleration and momentum do not exist. For practical purposes it immediately moves full speed upon beating it's flagella, and immediately comes to a stop when beating stops. What about other small objects? Is there some generalized way to decide the importance of momentum? Yes, the Reynold's number: Reynold's # η ρ vL = L is the size (radius for a sphere) ρ is the specific gravity (density for practical purposes). For a bacterium Reynold # 10 -5 For a fish 10 5 Another ramification of high Reynolds #: there may be turbulence. In this case Stokes' would not apply. Discuss springs and waves at low R.
Background image of page 2
BME 418, Quantitative Cell Biology Alan J. Hunt Now we turn from the prokaryotes to a group of organisms that appeared more recently on the planet, somewhere around 1.5 billion year ago from fossil records. The eukaryotes
Background image of page 3

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

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 6

Lecture 6 - BME 418, Quantitative Cell Biology Alan J. Hunt...

This preview shows document pages 1 - 4. Sign up to view the full document.

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