The covering of myelin around the axons is called the myelin sheath. This myelin sheath helps in transfer of information faster and also in complex processes of the brain. The process of myelination begins in the PNS (peripheral nervous system).
The myelinated section are seperated from each other with a gap called nodes of ranvier. Glial cells (oligodendrocytes) forms the myelin sheath in the central nervous system and schwann cells (glial cells) forms the myelin sheath in peripheral nervous system. The propagation of electrical impulse in the myelinated fibers is by saltatory conduction that is from one node to another.
Myelination refers to the process which forms a protective layer made up of lipid-containing substance fats around the neurons. This protective layer around the neuron is known as the myelin sheath.
The myelin sheath is formed by the Schwann cells in the peripheral nervous system by the extension and helical wrapping of the plasma membrane of the Schwann cells around neurons. similarly, Oligodendrocytes form the myelin layer around the neurons in the CNS.
Answer: is D. Mercury was used to treat many illnesses long ago, and after being deemed safe by modern doctors its use has increased in the past 100 years.
<span>Platelets - help the blood to clot. Clotting stops the blood from flowing out of the body when a vein or artery is broken. Red blood cells - carry oxygen White blood cells - ward off infection</span>
