Which of the following utilizes a cantilever to detect surface topography?
Atomic Force Microscopy detects surface topography using a flexible cantilever with sharp tip at end. As tip scans sample, interatomic forces deflect cantilever; laser reflected off back tracks deflection for feedback. This mechanical sensing produces height maps with sub-nanometer vertical resolution in air or liquid without stains or electron beams. Unlike TIRF relying on evanescent waves, or SEM/TEM requiring vacuum and electron optics, AFM operates via force interaction, providing 3D profiles of biomolecules, polymers, and live cells, plus measurement of elasticity and adhesion through for
Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.