Desmid Delegation

What am I looking at?

The main image shows a parade of individual desmids. And if you click on the right arrow, you’ll see an image showing eight desmids stacked on top of one another, with the smallest one in front and the largest one in back. The cell walls, visualized with a cellulose-binding dye known as Calcofluor white, are blue (1). Each cell houses two large chloroplasts, seen here in red (2) – one in each semicell, or half of a desmid. The chloroplasts didn’t require any dye for visualization; when they’re illuminated with green light, they emit red fluorescence due to the presence of chlorophyll.

Biology in the background

Desmids are a type of green algae; they come in many different shapes and sizes, but they all have one thing in common: they are made of symmetrical halves, called semicells. The “waist” of a desmid is called the isthmus; that’s where you can find a desmid’s nucleus. At first glance, the two halves seem to be mirror images of each other, but in fact one of them is rotated by 180 degrees. This makes them incredibly fascinating to look at – almost like living snowflakes. You can find them in water that is fairly acidic, with a low mineral and nitrogen content, such as ponds, swamps, or bogs.

Like plants, desmids obtain nutrients from carbon dioxide, water, and the energy of sunlight via the process of photosynthesis. Desmids often occupy the same ecosystems as aquatic carnivorous plants known as bladderworts and can be found inside their traps.

Desmids range from 40 micrometers to 300 micrometers, or roughly two times as small to four times as big as the width of a human hair.

Technique 

These images were taken using confocal microscopy.