#microalgae

diatoms are phytoplanktons(1) with a cell wall made of silica(2). this biologically created, hydrated silica(3) is also found in opal(4), not glass. while silicate glass is made of silica (hence the name), it also has other components added and is not (as far as i know) biologically produced. the cell wall of a diatom instead is more similar to silica [xero]gel(5), the packets that say "DO NOT EAT" and are used for keeping things dry(6), though silica xerogel is a dehydrated form of hydrated silica. the cell wall of a diatom is called a frustule, and many protists(7) have shells(8). the frustule of a diatom, made of silica, is used to prevent water loss. it is not unique to diatoms; radiolaria(9) also have silica shells (mineral skeletons).

being phytoplankton, diatoms are autotrophs (produce their own "food"(10)) that rely on photosynthesis. they use the sun to make sugars that they then break down for energy(11).

they also form other shapes, not just stars! i personally think the "fans" are pretty cool :3

they are a lot cooler than they sounded in the original post too =w= (linked: Wikipedia)

image by Damián H. Zanette via wikipedia.

their classification is unfortunately very muddy, as is most algae. i personally disagree with "algae" as a scientific classification(12) (just like "fish"(13)), but that's for a different post.

Snot and Jewels

Diatoms are tiny single-celled creatures found in water all over the world in a startling array of shapes and colours – earning them the nickname the jewels of the sea. Some species of these microalgae bob around in currents while others propel themselves – here computer software tracks the graceful movement of Craspedostauros australis from above. But underneath is a different story. Researchers discover C. australis steer themselves around using gusts of sticky mucilage pushed through slits in their undercarriage. Different patterns of gluey spurts, forced through differently shaped gaps, help them change direction as they glide. While not directly harmful to humans, algal mucilage, often referred to as “sea snot”, can harbour dangerous bacteria such as E.Coli. Yet, diatoms also produce up to half the world’s oxygen as a byproduct of their photosynthesis, highlighting our contrasting relationships with these ancient microscopic creatures.

Written by John Ankers

Video from work by Stefan Golfier and colleagues

B CUBE - Center for Molecular Bioengineering, TUD Dresden University of Technology, Dresden, Germany

Video originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)

Published in Proceedings of the National Academy of Science (PNAS), April 2026

Researchers from the University of Jena and the Leibniz Institutes in Jena have published new findings on the adaptability of the microalgae Chlamydomonas reinhardtii. The interdisciplinary study, largely carried out by scientists from the Cluster of Excellence Balance of the Microverse, shows how the tiny green alga can adapt its shape and metabolism under natural conditions without changing its genome. The research team investigated how the green microalga Chlamydomonas reinhardtii, a model organism in biology, undergoes a kind of "metamorphosis" in an acetate-rich, spatially structured environment modeled on natural rice paddy soils.

"The phytoplankton that populate oceans are known to play a key role in marine ecosystems and climate regulation. Like terrestrial plants, they store atmospheric CO₂, and produce half of our planet's oxygen via photosynthesis. However, the mechanisms that control their distribution remain poorly understood.

By studying the light perception process of diatoms, a group of phytoplankton, scientists from the CNRS and Sorbonne University discovered that these microalgae use light variation sensors which are codified in their genomes: phytochromes.

These photoreceptors enable them to detect changes in the light spectrum in the water column, thereby providing information regarding their vertical position within it. This function is especially important in turbulent aquatic environments subject to substantial water mixing—such as high latitude, temperate, and polar regions—in order to adjust their biological activity, in particular photosynthesis."

Carbelim’s free Microalgae Carbon Capture Calculator helps evaluate CO₂ capture, biomass productivity, system efficiency, and real-world assumptions.

A simple step toward more transparency in climate-tech.

A Liquid Tree? Scientists in Serbia Make Incredible Innovation

Dr. Ivan Spasojevic, Ph.D. in Biophysical sciences, and one of the authors on the project from the Institute for Multidisciplinary Research at the University of Belgrade, developed an innovative tool for reducing greenhouse gas emissions and improving air quality: the liquid tree. Also dubbed LIQUID 3, the novel creation is Serbia’s first urban photo-bioreactor, a solution in the fight for clean air. It contains six hundred litres of water and works by using microalgae to bind carbon dioxide and produce pure oxygen through photosynthesis.

The microalgae replace two 10-year-old trees or 200 square meters of lawn. . The advantage of microalgae is that it is 10 to 50 times more efficient than trees. 

Very interesting, especially in urban contexts that can’t support / be reconfigured to support more trees.