Meninges are membranes that cover and protect the brain and spinal cord.
There are three layers of meninges: Dura mater (closest to the bone), Arachnoid loosely around the brain, Pia mater is closely attached to the brain and spinal cord surface.
This process is known as a involuntary reflex.
<span>It has the advantage that only when the substrate is presence the genes responsible for its metabolism are turned on.</span>
Answer:
answer is d) all of these choices are correct.
Primary succession is ecological succession that begins in essentially lifeless areas, such as regions in which there is no soil or where the soil is incapable of sustaining life because of recent lava flows, newly formed sand dunes, or rocks left from a retreating glacier.