Diatom biology

Fucoxanthin is a xanthophyll, with formula C42H58O6. It is found as an accessory pigment in the chloroplasts of brown algae and most other heterokonts, giving them a brown or olive-green color. Fucoxanthin absorbs light primarily in the blue-green to yellow-green part of the visible spectrum, peaking at around 510–525 nm and absorbing significantly in the range of 450 to 540 nm.

thumb|upright=1.3|Scanning electron micrographs of frustules from some algae species - scale bar = 10 micrometres in a, c and d and 20 micrometres in b A frustule is the hard and porous cell wall or external layer of diatoms. The frustule is composed almost purely of silica, made from silicic acid, and is coated with a layer of organic substance, which was referred to in the early literature on diatoms as pectin, a fiber most commonly found in cell walls of plants. This layer is actually composed of several types of polysaccharides.

thumb|right|Strawberry anther with parallel thecae In biology, a theca (: thecae) is a sheath or a covering.

type of soil formed by sedimentation in estuaries

thumb|right|Filament of Aulacoseira, with an auxospore at the end Auxospores are specialised cells in diatoms that are produced at key stages in their cell cycle or life history. Auxospores typically play a role in growth processes, sexual reproduction or dormancy.

chemical compound

biogenic pelagic sediment located on the deep ocean floor