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Sachs, Julius von

(Encyclopedia)Sachs, Julius von fə zäks [key], 1832–97, German botanist. A professor at the Univ. of Würzburg from 1868, he was a founder of experimental plant physiology. He demonstrated the importance of tra...

Dinoflagellata

(Encyclopedia)dinoflagellata dīˌnōflăjˌəlätˈə, –lāˈtə [key], phylum (division) of unicellular, mostly marine algae, called dinoflagellates. In some classification systems this division is called Pyrrh...

Mohl, Hugo von

(Encyclopedia)Mohl, Hugo von ho͞oˈgō fən mōl [key], 1805–72, German botanist. He is noted for his research on the nature of protoplasm and chlorophyll and on the physiology of higher plant forms. Mohl was pr...

chloroplast

(Encyclopedia)chloroplast klōrˈəplăstˌ, klôrˈ– [key], a complex, discrete green structure, or organelle, contained in the cytoplasm of plant cells. Chloroplasts are reponsible for the green color of almost...

optical activity

(Encyclopedia)optical activity, the ability of asymmetric compounds to rotate the orientation of planar polarized light. Such compounds and their mirror images are know as enantiomers, or optical isomers. Although ...

deodorizer

(Encyclopedia)deodorizer or deodorant, substance used to absorb or eliminate offensive odors. Disinfectants such as hydrogen peroxide, chlorine, and chlorine compounds eliminate odors caused by microorganisms. Adso...

chelating agents

(Encyclopedia)chelating agents kēˈlātĭng [key]. Certain organic compounds are capable of forming coordinate bonds (see chemical bond) with metals through two or more atoms of the organic compound; such organic ...

algae

(Encyclopedia)algae ălˈjē [key] [plural of Lat. alga=seaweed], a large and diverse group of primarily aquatic plantlike organisms. These organisms were previously classified as a primitive subkingdom of the plan...

cyanobacteria

(Encyclopedia)cyanobacteria sīˌənōbăktĭrˈēə, sī-ănˌō– [key] or blue-green algae, photosynthetic bacteria that contain chlorophyll. For many years they were classified in the plant kingdom along with ...

Chrysophyta

(Encyclopedia)Chrysophyta krəsŏfˈətə [key], phylum (division) of unicellular marine or freshwater organisms of the kingdom Protista consisting of the diatoms (class Bacillariophyceae), the golden, or golden-br...

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