Q.Foetus development can be observed using

Ultrasound imaging uses sound waves beyond the range of human hearing, generated by the piezoelectric effect when an electric potential excites a crystal such as lead zirconate. The waves travel unimpeded through uniform tissue until they meet a different tissue boundary, where part of the wave reflects back to the same crystal and is converted into an electrical signal, displayed as an image built from these reflections. Being non-invasive and radiation-free, it is widely used to image …