Epithelial tissues are in constant interaction with their environment. Maintaining their functionality requires dynamic balance (homeostasis) and that their cell numbers are tightly regulated. This is ...

**Pre reqs:** [Free Body Diagrams](http://scienceblogs.com/dotphysics/2008/09/basics-free-body-diagrams.php), [Force](http://scienceblogs.com/dotphysics/2008/09 ...

The detection of physical forces is one of the most complex challenges facing science. Although Newton's apple has long solved the problem of gravity, imaging the physical forces that act in living ...

There are some things in life that just sort of happen. Desks get covered in dust and scraps of paper. Clothes get dirty and the laundry basket fills up. Weeds slowly creep across an untended ...

James is a published author with multiple pop-history and science books to his name. He specializes in history, space, strange science, and anything out of the ordinary.View full profile James is a ...

Forbes contributors publish independent expert analyses and insights. I write about physics, science, academia, and pop culture. It's impossible to talk about football these days without talking about ...