Bacillariophyta Flashcards
taxonomy based on?
- symmetry?
- bilateral (pennate)
- radial (centric) - ornamentations?
- Raphe? –> present or not? 1 or both? centric/eccentric?
- girdle bands –> number/open/closed..? - areolae
- striae? (in rows) –> parallel? radiate? …?
- loculae? (hexagonal) –> radial? tangential?
division of Diatoms from ecological point of view?
euplanktonic?
benthic?
what diatoms constitute the microphytobenthos?
Diatoms settling on natural substrates
what diatoms constitute microfouling?
Those that settle on artificial substrates
epiphytic diatoms- differentiation, how?
based on how they attach to substrate
adnate vs erect
(whole valve-face vs partial pads or stalks)
what’s their attachment?
which diatoms can attach?
benthic diatoms or periphyton
attachment of benthic diatoms or periphyton: How?
attachment of benthic diatoms or periphyton: How?
- pads or stalks
attachment of benthic diatoms or periphyton: How?
what is that?
role of diatoms as benthos?
- food source
- Epiphytic diatoms can become part of the food web, as they are eaten by many herbivorous organisms
- They secrete mucilage forming a biofilm, together with bacteria, which prepares the substrate for the colonization of multicellular algae and sessile animal species
what’s the third group of diatoms?
- meroplanktonic or ticopelagic diatoms
what are meroplanktonic or ticopelagic diatoms?
- before they were attached benthic forms
what do diatoms require for their cell wall?
what is composed of silica?
the frustules. ( cell wall)
how does availability of SiO2 influence the species composition?
- diff. species –> diff. needs
what is diatomaceous earth? how does it develop?
- Frustules of diatoms often do not wear away after the organism death
- accumulate in sediments
- can be preserved as fossils
Diatomaceous earth (diatomite), a silica-containing sedimentary rock, is a collection of diatom frustules found in the earth’s crust.
