In mathematics, the Fibonacci numbers or Fibonacci series or Fibonacci sequence are the numbers in the following integer sequence: (sequence A000045 in OEIS) By definition, the first two numbers in the Fibonacci sequence are 0 and 1, and each subsequent number is the sum of the previous two.
Tight Junctions. Tight junctions are found predominantly in epithelial tissues, such as intestinal brush border. Water and other fluids must be prevented from leaking between adjacent cells, so that body fluids do not gradually seep across the intestinal lining.
Graphic of junctions in animal cells. Tight junctions. Tight junctions block the flow of fluids between epithelial cells. For example, the cells that line the intestine are responsible for taking up nutrients from the gut. The nature of the material taken up must be controlled to block unwanted substances from entering our bodies. The control comes from the fact that materials must pass through receptors on the epithelial cell membranes. Tight junctions form a water tight seal and prevent material from passing between cells.