<span>Light given off from a hot object, in this case an incandescent bulb containing a hot filament, emits colors that appear smooth and continuous in wavelength, producing a bell curve. By contrast a hydrogen tube emit colors at different places on the spectrum, rather than continuously. For a white light, green, red, and blue must emit.</span>
You can extract the iron fillings from the sand by using a magnet
Those molecules that we can glean information about their position via concentration gradient are called morphogens.
<h3>What is concentration gradient?</h3>
The term concentration gradient refers to the difference in the amount of substance on two different sides. This gradient could be used to glean useful information about the molecule position.
Chemical molecules that impart positional information through their concentration gradient are called morphogens.
Learn more about concentration gradient: brainly.com/question/19589080