BI236 Lecture Notes - Lecture 18: Ultimate Tensile Strength, Triple Helix, Micronucleus
Document Summary
Link cells together-enabling them to function as a unit. Anchor the cytoskeleton to the and have intracellular attachment proteins on the inside of he cel and caherins protruding from the outer surface. Epithelial misses form barriers between inside and outside. Small molecules and ions pass directly from one cell to another. Allow adjacent cells to be in direct electrical and chemical communication with eachother. At least 15 types of collagens (speci c tissues) Triple helix > a rigid structure of 3 intertwined polypeptides. Lungs, arteries, skin, intestines (need to change shape) Cross-linked by covalent bonds between lysine residues. Relaxation > crosslinks causes network to recoil to original shape. Collagen becomes increasingly cross-linked and in exible, elastin are lost from tissues like skin. Therefore in older people > bones/joints are less exible and skin is wrinkled. Fibronectins lamenting > these glycoproteins bind to a family of transmembrane proteins called integriy on cell surface. Integriny > integrate the cytosketelon with the ecm.
