A recent "Hot Paper" summary in The Scientist not only brings us up to date on the latest skirmish in the battle over which cell is THE stem cell of the intestinal crypts, it also gives us a great Flash video that we can use to illustrate the process of maintaining the lining of the small intestine.
In my textbook Anatomy & Physiology 7th edition, Figure 25-18 (p. 853) shows the process by which stem cells in the intestinal crypts (of Lieberkuhn) produce daughter cells that move up and out of the crypt to replace cells lost at the apices of the intestinal villi.
The video embedded in the article in The Scientist is not narrated, and rather slow-moving at times, but it does a fantastic job of animating the process shown in textbook figure 25-18.
To link directly to the video, go to:
To view the video within the article go to . . .
Gut Churning: The discovery of an intestinal stem cell marker fuels an ongoing debate over the cells' location and propertiesNo matter how you get there, I suggest previewing it (duh-uh) and taking note of particular times in the sequence to which you may want to quickly navigate to avoid the slow parts (or skip parts not useful in your course). Or just slide the timing bar to the spot you want.
The Scientist Volume 23, Issue 7, Page 51
BONUS! Here are some FREE images of the intestinal villi and intestinal crypts from an early edition of Gray's Anatomy: