BIOL 225 2026/2027 | 75 Questions & Answers | Cell Biology, Microscopy, Cell Culture, DNA & Proteins

This BIOL 225 2026/2027 exam study guide contains approximately 75 questions, exercises, and correct-answer sets covering the fundamental principles of cell biology, microscopy, cell theory, cell structure, cell culture, molecular interactions, amino acids, and protein structure. The material begins with the historical foundations of cell biology, including Robert Hooke, Antonie van Leeuwenhoek, Schleiden, Schwann, and Virchow, before examining the cell as the fundamental unit of life, the relationship between cytology, biochemistry, and genetics, cellular dimensions, and the scientific method. A major section focuses on microscopy and cellular imaging. Students review magnification versus resolution, nanometers and micrometers, brightfield microscopy, phase-contrast microscopy, differential interference contrast microscopy, fluorescence microscopy, confocal microscopy, transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The questions examine how these techniques work, their relative resolving powers, their applications to living and fixed specimens, and their usefulness for visualizing structures ranging from whole cells to DNA. More advanced topics include fluorochromes, dichroic mirrors, GFP reporter systems, confocal Z-stacks, numerical aperture, wavelength, refractive index, and the principles underlying electron microscopy. The document then develops the universal features and molecular organization of cells, including DNA as hereditary information, templated replication, RNA transcription, protein synthesis, genes, catalysts, free-energy requirements, and the plasma membrane. It examines why cells remain small through surface-area-to-volume relationships and diffusion constraints and introduces cellular evolution through LUCA, Bacteria, Archaea, Eukaryotes, prokaryotic cells, and eukaryotic cells. Another substantial section covers cell culture and experimental cell biology. Topics include primary and secondary cultures, mass and clonal cultures, axenic cultures, suspension and semi-solid media, anchorage-dependent and anchorage-independent growth, extracellular matrix interactions, collagen, growth factors, serum, contact inhibition, monolayers, the Hayflick limit, transformed cancer cells, telomerase, and in vitro versus in vivo experimentation. The material also reviews Eagle's Basal Medium, essential amino acids, vitamins, salts, glucose, antibiotics, and other requirements for mammalian cell culture. The guide includes the historically significant HeLa cell line and Henrietta Lacks, followed by cryobiology and cryopreservation. Students encounter the benefits of maintaining biological backups, risks of cell-culture contamination and genomic instability, freezing-induced cellular damage, crystallization, and common cryoprotective agents such as DMSO and glycerol. These topics provide useful preparation for students studying laboratory cell biology and biomedical research methods. The final portion moves into biochemistry and protein structure, addressing hydrogen bonding, van der Waals interactions, water cohesion, hydrophilic and hydrophobic interactions, entropy, amino-acid R groups, stereochemistry, L- and D-isomers, glycine, condensation reactions, peptide bonds, and protein primary and secondary structure. Alpha helices, beta sheets, polypeptide organization, amino and carboxyl termini, and the molecular interactions that stabilize protein structures are included, making the document useful for integrated cell biology and introductory molecular biology revision. Relevant students: This study resource is particularly relevant for BIOL 225 students, undergraduate biology majors, cell biology students, molecular biology students, biomedical science students, biotechnology students, biochemistry students, pre-medical and pre-health students, laboratory science students, and learners preparing for examinations involving microscopy and cell culture. It is especially useful for students who need practice questions covering both conceptual cell biology and laboratory techniques. The uploaded material identifies the course as BIOL 225 but does not name a university or college; therefore, University Not Specified is used rather than assigning an unsupported institution. 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