One difference between mechanical and electromagnetic waves is that mechanical waves need a medium to pass through (solid, liquid, gas). EM waves can travel through matter or though a vacuum. In regards to telecommunications, EM waves can be radio waves, these are used in TV's, phones, computers, radios. Mechanical waves somewhat relate to this since radios produce sound;so an EM wave would turn into a mechanical vibration inside a speaker then sound would be produced.
Karyotyping is <u>a test to examine chromosomes in a sample of cells</u>. This test can help identify genetic problems as the cause of a disorder or disease.