Radioactive atoms are inherently unstable; over time, radioactive "parent atoms" decay into stable "daughter atoms." When molten rock cools, forming what are called igneous rocks, radioactive atoms are trapped inside. ... Scientists date igneous rock using elements that are slow to decay, such as uranium and potassium.
They are collagen fibers, reticular fibers, and elastic fibers.
<span>Sheaths of myelin produced by SCHWANN cells often enclose axons outside of the brain and spinal cord. Schwann cells are the cells in the peripheral nervous system that are responsible for producing myelin sheath that occurs around the neuronal axon. These cells get their name from Theodor Schwann who discovered them.</span>
A mother's diet before conception can permanently affect how her child's genes function, according to a study published in Nature Communications. A 2003 study found that a female mouse's diet can change her offspring's coat color by permanently modifying DNA methylation.
