搜尋結果
2024年10月28日 · algae, members of a group of predominantly aquatic photosynthetic organisms of the kingdom Protista. Algae have many types of life cycles, and they range in size from microscopic Micromonas species to giant kelps that reach 60 metres (200 feet) in length.
2024年10月28日 · Division-level classification, as with kingdom-level classification, is tenuous for algae. For example, some phycologists place the classes Bacillariophyceae , Phaeophyceae , and Xanthophyceae in the division Chromophyta, whereas others place each class in separate divisions: Bacillariophyta, Phaeophyta, and Xanthophyta .
2024年10月28日 · Algae - Photosynthesis, Diversity, Ecology: The size range of the algae spans seven orders of magnitude. Many algae consist of only one cell, while the largest have millions of cells. In large, macroscopic algae, groups of cells are specialized for specific functions, such as anchorage, transport, photosynthesis, and reproduction ...
algae, Members of a group of mostly aquatic photosynthetic organisms (see photosynthesis) that defy precise definition. They range in size from the microscopic flagellate Micromonas to giant kelp that reach 200 ft (60 m) in length.
2024年9月6日 · Blue-green algae, any of a large, heterogeneous group of prokaryotic, principally photosynthetic organisms. Cyanobacteria resemble the eukaryotic algae in many ways, including morphological characteristics and ecological niches, and were at one time treated as algae, hence the common name of.
Green algae, members of the division Chlorophyta, comprising between 9,000 and 12,000 species. The photosynthetic pigments (chlorophylls a and b, carotene, and xanthophyll) are in the same proportions as those in higher plants. The typical green algal cell, which can be motile or nonmotile, has a.
2024年10月28日 · Algae - Photosynthesis, Diversity, Nutrition: Algal cells are eukaryotic and contain three types of double-membrane-bound organelles: the nucleus, the chloroplast, and the mitochondrion. In most algal cells there is only a single nucleus, although some cells are multinucleate. In addition, some algae are siphonaceous, meaning the ...
Red algae, (division Rhodophyta), any of about 6,000 species of predominantly marine algae, often found attached to other shore plants. Their morphological range includes filamentous, branched, feathered, and sheetlike thalli.
2024年10月3日 · Seaweed, any of the red, green, or brown marine algae that grows along seashores. Seaweeds are generally anchored to the sea bottom or other solid structures by rootlike ‘holdfasts,’ which perform the sole function of attachment and do not extract nutrients as do the roots of higher plants.
Ulothrix, genus of filamentous green algae (family Ulotrichaceae) found in marine and fresh waters. Each cell contains a distinct nucleus, a central vacuole, and a large thin chloroplast with at least one pyrenoid.
