yellow-green algae
yel′low-green` al′gae
n.pl.
| Noun | 1.yellow-green algae - any alga of the division Chrysophyta with its chlorophyll masked by yellow pigment |
| 单词 | yellow-green algae | ||
| 释义 | yellow-green algaeyel′low-green` al′gaen.pl.
Yellow-green Algaeyellow-green algae[′yel·ō ¦grēn ′al·jē]Yellow-green Algae(Xanthophyta, also Heterocontae), a division (phylum) of plants. They are unicellular, colonial, or multicellular organisms, free-swimming or sessile, with yello wish-green chromatophores containing, besides chlorophyll, a large quantity of yellow pigments— xanthophyll and β-carotene. They are found chiefly in fresh water and sometimes in soil and sea water. The majority of yellow-green algae are autotrophic organisms that synthesize oils, volutin, and other substances; some of the yellow-green algae are heterotrophic organisms, and a few are holozoic. Some unicellular yellow-green algae are motile and have pulsating vacuoles and eyelets and usually two flagella of different length and structure (hence the second name— Heterocontae). The cells of the yellow-green algae are mononuclear, more rarely polynuclear, and are often surrounded by a hard sheath of two halves containing principally pectin. Yellow-green algae reproduce by binary fission, zoospores, and nonmotile spores. The sexual process, isogamy, is known in only two genera. Spores and cysts are the resting forms. In the USSR, 82 genera (344 species) of freshwater yellow-green algae are known. IU. E. PETROV yellow-green algae
Words related to yellow-green algae
|
||
| 随便看 |
|
英语词典包含2567994条英英释义在线翻译词条，基本涵盖了全部常用单词的英英翻译及用法，是英语学习的有利工具。