Cilia are slender, microscopic, hair-like structures or organelles that extend from the surface of nearly all mammalian cells (multiple or single).ource: Amelia Shoemark. ' Motile ' (or moving) cilia are found in the lungs, respiratory tract and middle ear. These cilia have a rhythmic waving or beating motion (see right). They work, for instance, to keep the airways clear of mucus and dirt, allowing us to breathe easily and without irritation.
Share. The visible light spectrum is the section of the electromagnetic radiation spectrum that is visible to the human eye. It ranges in wavelength from approximately 400 nm (4 x 10 -7 m) to 700 nm (7 x 10 -7 m). It is also known as the optical spectrum of light. By Andrew Zimmerman Jones.
Visible spectrum. The visible spectrum is a very small portion of the electromagnetic spectrum that can be seen by human eyes. This is shown in the figure below, which is not to scale. The exact boundaries of each type of wave are not precisely defined and often different authors have slightly different values.he limit between ionizing and non-ionizing radiations is located somewhere in the UV region, but it's not clearly defined and somehow fuzzy. A photon energy of 10 eV (corresponding to 124 nm) is often considered the threshold between ionizing and non-ionizing radiation, but there is no consensus on this topic.