Abstarct: Today the use of mathematical sciences in biology, has a special place and is considered as a scientific benchmark for research. Presenting mathematical theories, statistics and probability, theoretical study of diseases due to disorders in the mextabolic pathway or genetic changes and building computational algorithm and modeling to answer the questions of biological sciences, are some of the most significant applications of mathematics in biology. In this thesis we intend to discuss some applications of mathematics in biology, especially applications of coding theory in cellular and molecular biology. First, we study skew cyclic codes; linear codes over finite fields obtained by left ideals of the quotient ring of noncommutative skew polynomial rings. Then, we construct reversible DNA codes by using the skew cyclic codes over F_(4^(2S ) ). We also examine how the existence and properties of skew cyclic codes relate to the structure of reversible DNA codes. Finally, we will show that the dual codes of skew cyclic codes are also reversible DNA codes and skew self-reciprocal polynomials are palindromic.