... by epithelial cells.9 As a result of this diffusion of water, airways become blocked and pancreatic proteins turn inactive. An Account of the Absorption and Secretion of Cl-, Na+, and Proteins An inward, electrochemical Na+ gradient is generated by the Na+, K+-ATPase pump located in the basolateral membrane (the cell side facing the organ it is lining). A basolateral co-transporter then uses the ... done in such a way that when the apical Cl-channels within the membrane spanning domain open, Cl- diffuse passively with their gradient through the cell membrane.4 In pancreatic duct cells, a...

• Word Count: 2162
• Approx Pages: 9

... 9 different neuraminidase serotypes (different types of the proteins) discovered (mvm, 10/10/02). However there has only been three HA subtypes (H1 - 3) and two NA subtypes (N1, N2) discovered in humans (mvm, 10/10/02). Antigenic shift only ever occurs in the influenza A virus. This occurs when there is a rapid ... of no threat. The subtype of the influenza virus is also determined using the antigenicity of neuraminidase (NA). A spike of NA contains 4 NA monomers, hence is called a tetramer (angelfire, 9/10/02). The head of each NA molecule is topped with a box like structure. The catalyt...

• Word Count: 1687
• Approx Pages: 7
• Grade Level: High School

... three distinct groups that Greenberg recognized on linguistic grounds. This concludes that Amerindians appear to have reached the Americas in a migration much older and more complex than those of later Na-Dene and Eskimo-Aleut speakers, and that there may have been more than one Amerindian migration. Genetic data indicates that Amerindians arrived at least 33,000 years ago, but this ... ...

• Word Count: 1626
• Approx Pages: 7
• Has Bibliography
• Grade Level: Undergraduate