Report Abuse. X-radiation (composed of X-rays) is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (3 Ã 1016 Hz to 3 Ã 1019 Hz) and energies in the range 120 eV to 120 keV.hen x-rays were first discovered, scientists didn't know much about them, so they called them X-rays because X in science is often used to designate an unknown as in Planet X or solve for X They were also sometimes called Rontgen Rays after the man who discovered them.
1. calcium ion-ion of calcium; a factor in the clotting of blood. factor IV. atomic number 20, Ca, calcium-a white metallic element that burns with a brilliant light; the fifth most abundant element in the earth's crust; an important component of most plants and animals.. calcium ion-ion of calcium; a factor in the clotting of blood. factor IV. atomic number 20, Ca, calcium-a white metallic element that burns with a brilliant light; the fifth most abundant element in the earth's crust; an important component of most plants and animals.
Calcium in biology. Calcium ions (Ca2+) play a vital role in the physiology and biochemistry of organisms and the cell. They play an important role in signal transduction pathways, where they act as a second messenger, in neurotransmitter release from neurons, in contraction of all muscle cell types, and in fertilization. Many enzymes require calcium ions as a cofactor, those of the blood-clotting cascade being notable examples.