Tambunan, E.; Sitepu, S. C. br; Witin, T. A.; Arwita, W. Analisis Penerapan Model Pembelajaran Problem Based Learning Pada Pelajaran Biologi Materi Sistem Ekskresi Kelas X SMA Negeri 4 Binjai: (Analysis of the Application of the Problem Based Learning Model in Biology Lessons on the Excretory System Material for Class High School 4 Binjai). Biodik 2024, 10, 172-180.