Because they retain the capacity to proliferate and

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: an animal, stem cells play a critical role in the maintenance of most tissues and organs. The key property of stem cells is that they divide to produce one daughter cell that remains a stem cell and one that divides and differentiates (Figure 17.17). Because the division of stem cells produces new stem cells as well as differentiated daughter cells, stem cells are selfrenewing populations that can serve as a source for the production of differentiated cells throughout life. The role of stem cells is particularly evident in the case of several types of differentiated cells, including blood cells, sperm, epithelial cells of the skin, and epithelial cells lining the digestive tract—all of which have short life spans and must be replaced by continual cell proliferation in adult animals. In all of these cases, the fully differentiated cells do not themselves proliferate; instead, they are continually renewed by the proliferation of stem cells that then differentiate to maintain a stable number of differentiated cells. Stem cells have also been identified in a variety of other adult tissues, including skeletal muscle and t...
View Full Document

This note was uploaded on 08/25/2009 for the course BIO 315 taught by Professor Steiner during the Spring '08 term at Kentucky.

Ask a homework question - tutors are online