<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>
A polymer is made up of monomers. A monomer is a unit that occurs in repetitive chains. Lipids do not occur in repetitive chains, so they are not classified as monomers. Since they're not monomers, they can't make up polymers, either.
The answer is C. mycorrhizae.
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Both glycerophospholipids and sphingolipid structures are asymmetrically distributed in the two layers of the phospholipid bilayer. Sphingolipids are membrane lipids that have a ceramide backbone while glycerophospholipid has glycerol present in its membrane lipids. Sphingolipids may or may not be present.