This book focuses on mathematical models in biology and utilizes difference equations, matrix algebra, and Markov chains as the main mathematical tools.  In addition, MATLAB, a computer algebra system, as well as cooperative learning initiatives are integrated. The main theme of the book is the modeling of biological and ecological systems using linear and nonlinear difference equations and systems of difference equations. Readers are provided with examples and exercises that guide them through the discovery of mathematical concepts and exploration of the connection between biology and mathematics. Readrs are also introduced to various models in biology while utilizing MATAB applications to investigate and analyze the models that are represented by a single difference equation, a system of difference equations, or a matrix equation.  The book investigates situations that are modeled by first-order linear difference equations such as population dynamics of a single species and drug administration, and models represented by nonlinear first-order difference equations such as logistic growth model, maximum sustainable yield, and harvest strategies are explored. Markov chains are introduced and used to investigate a model of population movement between a city and its surrounding suburbs, as well as a model that utilizes Markov chains in genetics. Innovative ways of introducing eigenvalues and eigenvectors through age-structured population models are discussed, and the book concludes with population models of interacting species.