The bonds between the carboxyl and amine groups of the amino acids cause the straight chain to fold and twist, forming the structure of a protein.

Secondary: H-bond between carboxyl and amine groups of amino acid cause straight chain to fold and twist forming

in cartography, a contour line (often just called a "contour") joins points of equal elevation (height) above a given level, such as mean sea level. a contour map is a map illustrated with contour lines, for example a topographic map, which thus shows valleys and hills, and the steepness or gentleness of slopes.

explanation: