Answer:
He meant that the supporting cells form a insulating coat on the nerve fibre called myelin seath. The myelin Sheath act similar to the rubber coating of household wiring because it electrically insulates the nerve fibre and speeds of conduction of nerve impulse..
Explanation:
- The supporting cells of the nervous system are together called neuroglia or glial cells.
- Unlike neurons these cells can divide in the mature nervous system and do not conduct nerve impulse.
- Out of six types of glial cells, four are located in the central nervous system (CNS) and they are;astrocytes, oligodendrocytes, ependymal cells and microglia.
- The remaining two types are the part of Peripheral nervous system (PNS) and include Schwann cells and Sattelite cells.
- Among these , the oligodendrocytes of the CNS and Schwann cells of the PNS forms myelin sheath on the axons of the nerve cell that act similar to the rubber coating on the household wiring.
- The myelin sheath electrically insulates the axon of a neuron and increase the speed of conduction of nerve impulse.
Answer:
desolate or dreary; unhappy or miserable, as in feeling, condition, or appearance.
lonely and sad; forsaken.
expressive of hopelessness; despairing: forlorn glances.
bereft; destitute: forlorn of comfort.
Explanation:
hope this helps
Break down your food into nutrients for your body
Answer:
Whether or not a given isotope is radioactive is a characteristic of that particular isotope. Some isotopes are stable indefinitely, while others are radioactive and decay through a characteristic form of emission. As time passes, less and less of the radioactive isotope will be present, and the level of radioactivity decreases. An interesting and useful aspect of radioactive decay is half-life, which is the amount of time it takes for one-half of a radioactive isotope to decay. The half-life of a specific radioactive isotope is constant; it is unaffected by coTnditions and is independent of the initial amount of that isotope.
Consider the following example. Suppose we have 100.0 g of tritium (a radioactive isotope of hydrogen). It has a half-life of 12.3 y. After 12.3 y, half of the sample will have decayed from hydrogen-3 to helium-3 by emitting a beta particle, so that only 50.0 g of the original tritium remains. After another 12.3 y—making a total of 24.6 y—another half of the remaining tritium will have decayed, leaving 25.0 g of tritium. After another 12.3 y—now a total of 36.9 y—another half of the remaining tritium will have decayed, leaving 12.5 g. This sequence of events is illustrated in Figure 15.1 “Radioactive Decay”.
Explanation:
