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1. a stain, spot, or thickening; in anatomy, an area distinguishable by color or otherwise from its surroundings. Often used alone to refer to the macula retinae.
2. a discolored spot on the skin that is not raised above the surface; called also macule.
3. a corneal scar that can be seen without special optical aids; it presents as a gray spot intermediate between a nebula and a leukoma.
4. macula lutea. adj., adj mac´ular, mac´ulate.
macula atro´phica a white atrophic patch on the skin.
macula ceru´lea a blue patch on the skin seen in pediculosis.
macula cribro´sa a perforated spot or area; one of three perforated areas (inferior, medial, and superior) in the wall of the vestibule of the ear through which branches of the vestibulocochlear nerve pass to the saccule, utricle, and semicircular canals.
macula den´sa a zone of heavily nucleated cells in the distal renal tubule that feed information to the juxtaglomerular cells.
macula fla´va a yellow nodule at one end of a vocal cord.
macula folli´culi follicular stigma.
macula germinati´va germinal area; the part of the ovum where the embryo is formed.
macula lu´tea (macula lu´tea re´tinae) (macula re´tinae) an irregular yellowish depression on the retina, lateral to and slightly below the optic disk; receives and analyzes light only from the center of the visual field.
macula sac´culi a thickening on the wall of the saccule where the epithelium contains hair cells that receive and transmit vestibular impulses.
macula utri´culi a thickening in the wall of the utricle where the epithelium contains hair cells that are stimulated by linear acceleration and deceleration and by gravity.
a closely packed group of densely staining cells in the distal tubular epithelium of a nephron, in direct apposition to the juxtaglomerular cells; they may function as either chemoreceptors or as baroreceptors feeding information to the juxtaglomerular cells.
macula densaA short, specialised region in the distal renal tubule where specialised cells with large and densely packed granules converge. The macula densa is part of the juxtaglomerular apparatus.
mac·u·la den·sa(mak'yū-lă den'să)
A closely packed group of densely staining cells in the distal tubular epithelium of a nephron, in direct apposition to the juxtaglomerular cells; they may function as either chemoreceptors or as baroreceptors feeding information to the juxtaglomerular cells.