| features of fibrous protein | repitivive regular sequences of amino acids
polypeptide chains form long paraellel strands
support and structural functions |
| explain what collegen is | builds strength between connective tissue, extremely strong and stable. very high tensile strength and so is able to withstand immense pulling forces without stretching. it can still bend around a join as it flexes during movment. |
| how is collagen made for its role. p1 | its primary structure is largely a repeat of the amino acids sequence glycine-proline-alanine, which forms an unbranched polypeptide chain
collagen made up of 3 such poltypeptide chains wound in a triple helix that is held together by hydrogen bonds between the peptide bond NH of a glycine and a peptide c=o (carbonyl) group of amino acid in the adjacent polypeptide. |
| how is collagen made for its role p2 | as every third amino acid is the relatively small and compact glycine molecule, the triple helix produced is very tighytly wound. larger amino acids would produce a more loosely wound, and therefore less strong, triple helix |
| how is collagen made for its role p3 | the triple stranded molecules run parallel to others, and in most types of collagen these form even stronger units called fibrils, with fibrils forming collagen fibres |
