The Unsung Heroes of Ecosystems #Protista Explained

preview_player
Показать описание
The Unsung Heroes of Ecosystems #Protista Explained Protista, unicellular organisms, microbial diversity, protista examples, microbiology education, eukaryotic organisms, protista importance, protist classification, biology, bacteria, importance of protists, protista classification, algae and protozoa, protista facts, evolution, protista ecology, importance of protista, protista habitat, protists, protista overview, algae, marine protists, environmental roles, protist habitat, algae types, eukaryotic life, biological significance
This group includes diatoms and golden algae (desmids). They are found
in fresh water as well as in marine environments. They are microscopic
and float passively in water currents (plankton). Most of them are
photosynthetic. In diatoms the cell walls form two thin overlapping shells,
which fit together as in a soap box. The walls are embedded with silica
and thus the walls are indestructible. Thus, diatoms have left behind
large amount of cell wall deposits in their habitat; this accumulation over
billions of years is referred to as ‘diatomaceous earth’. Being gritty this
soil is used in polishing, filtration of oils and syrups. Diatoms are the
chief ‘producers’ in the oceans.
These organisms are mostly marine and photosynthetic.
They appear yellow, green, brown, blue or red depending
on the main pigments present in their cells. The cell wall
has stiff cellulose plates on the outer surface. Most of
them have two flagella; one lies longitudinally and the
other transversely in a furrow between the wall plates.
Very often, red dinoflagellates (Example: Gonyaulax)
undergo such rapid multiplication that they make the
sea appear red (red tides). Toxins released by such large
numbers may even kill other marine animals such as
fishes
Рекомендации по теме