In this section, the definition of science is made, and it is emphasized that various scientists work in more than one field, not in a single field, and the relationship between Mathematics, Physics, and Chemistry and Biology is emphasized. Basic concepts and derived concepts are specified; their definitions, symbols, formulas, and units in various systems are exemplified; and concept analyses and unit analyses are performed. Information is given about the system theory that is included in all fields of science, and biological examples are made by establishing its relationship with cybernetics. The feedback mechanism is evaluated especially over hormones. Both analytical geometry and biological analyses are made over directly proportional and inversely proportional quantities. By establishing a relationship between blood parameters and proportional quantities, blood collection locations in different animal species are specified, and anemia typing and leukocyte differences are examined with some special case questions. Biological relationships are established between derivatives and integrals in mathematics and trigonometric and logarithmic functions, and especially the relationship between the pH concept and the exponential function in X-ray physics is evaluated. At the end of each section, the subject is detailed with explanatory questions.