Within this
body part, lymph acquires particles that help immune system function. According
to Merriam dictionary, immune system is defined as “the bodily system that protects the body
from foreign substances, cells, and tissues by producing the immune response
and that includes especially the thymus, spleen, lymph nodes, special deposits
of lymphoid tissue (as in the gastrointestinal tract and bone marrow),
macrophages, lymphocytes including the B cells and T cells, and antibodies.”
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<span>The fluid flows through the interventricular foramen into the third ventricle, is augmented by fluid formed by the choroid plexus of this ventricle, and passes through the cerebral aqueduct to the fourth ventricle, which also possesses a choroid plexus. The CSF from all theses sources , as well as any formed in the central canal of the spinal cord, escapes from the fourth ventricle into the subarachnoid space through the median aperture and lateral aperture.</span>
Fish, reptiles, amphibians, reptiles and mammals
Mylenation - an insulator along the axon
