"Journey to the Microcosmos: Slime Molds--When Micro Becomes Macro" explores slime molds as remarkable eukaryotic organisms that challenge traditional classification. The video explains how slime molds differ from fungi, introduces major groups such as dictyostelids and myxomycetes, and focuses on Physarum polycephalum as a model organism. Key biology concepts include cells, nuclei, amoebas, spores, plasmodium, phagocytosis, evolution, and organism classification. It also highlights how slime molds move, grow, solve mazes, optimize nutrient pathways, and demonstrate forms of learning studied in microbiology and life science. With microscopy-based observation and clear scientific vocabulary, the video supports curriculum topics in cell biology, microorganism behavior, classification of living things, and scientific inquiry. Part of the "Journey to the Microcosmos" series.