Morphology gross

A number of substances may interfere with stool examination. Particulate materials such as barium, antacids, kaolin, and bismuth compounds interfere with morphologic examination, and oily materials such as mineral oil create small, refractile droplets that make examination difficult. Antimicrobial agents, particularly broad-spectrum antimicrobial agents, may suppress amebae. If any of these substances have been used, specimens should not be submitted until the substances have been cleared (generally 5 to 10 days). A fecal specimen may appear satisfactory by gross examination when there is still barium, etc., which can interfere with microscopic examination. 

The identification of dematiaceous fungi ultimately rests upon their microscopic morphology and, to a lesser extent, upon their gross... 

Higher mortality associated with molting and gross morphological deformities at concentrations as low as 0.5 pg/L... 

Chromosomal mutations are recognised as morphological alterations in the gross structure of chromosomes, that is, they are structural aberrations which can be detected microscopically. Compounds which cause chromosome damage are called clastogens. 

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