This lecture introduces the fundamentals of systems biology with a focus on metabolism modeling and analysis. Topics covered include kinetic models, signaling circuits, transcription dynamics, and spatial effects. Emphasis is placed on understanding metabolic flux distributions, thermodynamics in metabolism, and omics integration. The lecture also explores the complexity of biological systems, enzyme classification, and genome-scale metabolic modeling. Students will learn about the central carbon metabolism of E. coli, metabolic flux analysis, and constraint-based modeling to achieve specific objectives within defined constraints.