The most basic answer is that the electromagnetic spectrum is the range of all the wavelengths (frequencies) of electromagnetic radiations. It basically describes the range of light in our universe.
Visible light is the only part of the EM spectrum we can see, but there are many kinds of invisible light waves. There are seven kinds of wavelengths in the EM spectrum: radio, microwave, infrared, visible, ultraviolet, x-ray, and gamma. Radio waves have the lowest frequency, and therefore have the largest wavelengths, which means that gamma rays have the highest frequencies and smallest wavelengths in the electromagnetic spectrum.
Boiling the broth in both flasks ensured that any pre-existing organisms such as bacteria were killed.
Had the broths not been boiled, both the flasks would have had bacterial growths in them, making the experiment inconclusive. This removal of pre-existing organisms when conducting investigations is still carried out, such as when creating a colony of bacteria on a petri dish or preparing a batch of alcohol through fermentation.
<span>Thousands of years of isolation between tribal groups</span>
The molecules that contain instructions for building proteins are <em>B.) DNA molecules</em><em />
DNA consists of molecules called nucloetides. Each nucleotide contains a phosphate group, sugar group, and nitrogen base. There are four bases: cytosine (C), thymine (T), adenine (A), and guanine (G). The order of these bases is what determines the genetic code, or DNA instructions.
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