Q.What are the shapes of a bacillus and coccus? (Refer to chapter from Biology, Std. XI)

Nanoscience is the study of phenomena and manipulation of materials at atomic, molecular and macromolecular scales, where properties differ significantly from those at a larger scale -- a size regime where a material's ordinary bulk properties genuinely change, purely as a function of particle size, without any change in chemical identity. Nanotechnology is the applied, engineering side of the same subject: the design, characterisation, production and application of structures, devices and systems by deliberately controlling their shape and size at the nanometre scale. The word 'nano' comes from the Greek for dwarf, though the actual nanometre scale is smaller than that suggests: conventionally 1-100 nm, where one nanometre is one-billionth of a metre (1 nm = 10⁻⁹ m). A nanomaterial is a material with structural components having at least one dimension in this 1-100 nm range -- larger than single atoms but smaller than bacteria and cells -- classified by how many of its three dimensions are nanoscale: zero-dimensional (0D, all three dimensions nanoscale, e.g. nanoparticles, quantum dots), one-dimensional (1D, two dimensions nanoscale, e.g. nanowires, nanotubes), and two-dimensional (2D, one dimension nanoscale, e.g. thin films). Nanochemistry is the combination of chemistry and nanoscience: designing and synthesising nanoscale materials and organising them into functional architectures, spanning chemical, physical, materials-science, engineering, biological and medical applications.