(biochemistry) a long linear polymer of nucleotides found in the nucleus but mainly in the cytoplasm of a cell where it is associated with microsomes; it transmits genetic information from DNA to the cytoplasm and controls certain chemical processes in the cell. see more on Definitions.net Â».
It forms a partition between the nasal passages and the mouth. On the anterior portion of the roof of the hard palate are the rugae, irregular ridges in the mucous membrane that help facilitate the movement of food backwards towards the pharynx.This partition is continued deeper into the mouth by a fleshy extension called the soft palate.he hard palate is a thin horizontal bony plate of the skull, located in the roof of the mouth.
The anterior surface of the body [Fig. 2] presents, in the middle line, a vertical crest, the sphenoidal crest, which articulates with the perpendicular plate of the ethmoid, and forms part of the nasal septum. On either side of the crest is an irregular opening leading into the corresponding sphenoidal air sinus.he superior surface of the body [Fig. 1] presents in front a prominent spine, the ethmoidal spine, for articulation with the cribriform plate of the ethmoid bone; behind this is a smooth surface slightly raised in the middle line, and grooved on either side for the olfactory lobes of the brain.