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These figures show the protein structure of hemocyanin, the…

These figures show the protein structure of hemocyanin, the copper-containing oxygen transport protein in arthropods, octopuses, and squids. The two figures are of the same protein, one a front view and a back view—a 180o rotation about the vertical axis. The small diamond-shaped dicopper structure is the in the center. This molecule is responsible for the blue color of the oxygenated blood of these animals. Image Description A 3D representation of a protein structure, displaying its complex folding and various regions. The protein features several alpha helices, depicted as spirals, and beta sheets, depicted as arrows, interconnected by loops. The structure is colored with a gradient from blue (N-terminus) to red (C-terminus), illustrating the flow of the polypeptide chain. This visual highlights the intricate architecture crucial for the protein’s specific function. In the three-strand flat ribbon structure, the arrowhead of the middle strand is in the opposite direction from the two other strands. Referring to the figure, briefly describe the secondary structure of the three-strand flat ribbon structure at the top of this protein. (1pt.) The sequence of the vertical helix on the right-hand side of the first figure is IPELEEHLKEI. Briefly explain why this helix has both a polar and a nonpolar side and which way you would expect to find the nonpolar side facing relative to the rest of the protein’s structure. (2 pts.)

Questions 2–9 refer to this toxic peptide. General Instructi…

Questions 2–9 refer to this toxic peptide. General Instructions: If the question does not require you to draw a structure, you may answer using either the full name of an amino acid or use its three-letter or single-letter code.   Many animal toxins are peptides. One of these is a 42-residue toxic peptide found in the South American rattlesnake, Crotalus durissus terrifics. The primary sequence of this peptide is shown below and its structure is shown in the figure. YKQCHKKGGHCFPKEKICLPPSSDFGKMDCRWRWKCCKKGSG Image Description and Attribution A 3D protein structure showing the positions of cysteine residues (Cys4, Cys11, Cys18, Cys30, Cys36, and Cys37) highlighted in yellow. The protein has an N-terminal (N) and C-terminal (C) with distinct secondary structures: alpha-helices in red and beta-sheets in blue, connected by green loops. The cysteine residues form disulfide bonds, contributing to the protein’s stability and shape. Yikrazuul, Structure of Crotamin, Wikimedia Commons, (CC BY-SA 3.0).