One Coleps makes two, cell division

• Alga: Coleps
• Order: Prorodontida Corliss, 1974
• Family:  Colepidae Ehrenberg, 1838
• Genus: Coleps Nitzsch, 1827

Coleps is a barrel-shaped ciliate, notable for its regularly arranged ectoplasmic shields, or platelets, of calcium carbonate. The covering with the scales is sometimes completely or partly absent immediately after an amitotic division (direct cleavage of the nucleus without the formation of mitoses). This is clearly visible in the accompanying video. Cell division took approximately 45 minutes. The color of the cell is usually brown and is less determined by the color of the food consumed than with other ciliates.

Giant chromosomes

Giant chromosomes (or polytene chromosomes) are found in the cells of larvae of flies and mosquitoes, in springtails and in some other invertebrates. In mosquitoes we find them, for example, in the cells of the bug Chironomus and in the cells of flies like Drosophila (fruit fly). The growth of these larvae occurs because the cells grow in size, not in number. The chromosomes also grow in size because the DNA multiplies many times without the cell or nucleus dividing. A giant chromosome therefore consists of hundreds to thousands of undivided chromatides. The chromatids have a sequence of light and dark bands, the so-called chromomers. Due to the dimensions of the giant chromosomes, these bands are very noticeable. On the basis of these bands it is easy to indicate where the genes are located on the giant chromosome (called ‘gene mapping’)

On the image, swellings, so called puffs, can be seen at particular sites along the length of the polytene chromosome. These are diffuse uncoiled regions where transcription is actively taking place.

Polytene = composed of many chromatides

Chromatides = the two identical parts of a chromosome
Gene = a piece of DNA containing certain hereditary characteristics

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New Zealand flax

Phormium tenax or New Zaeland flax are evergreen perennials, making a large clump of leathery, strap-shaped leaves coming to a decided point, with tall panicles of small, tubular flowers in summer.

New Zealand flax is an excellent fiber plant, hence the association with real flax (Linum usitatissimum) that is grown in Europe. The fibers of the leaves, up to 2 m long, were used by the Maori to make clothes, bags and shoes, and later the Europeans made rope and sails. All parts of the plant were used: for medicine made from roots, face powder from flower pollen and old blooming stems roped together as rafts.

What exactly is the function of our red blood cells?

Red blood cells (RBCs) also known as erythrocytes are the most abundant cell in the human body. With a staggering number of 25 trillion cells, yes TRILLION, the red blood cells make up around 80% of all your cells. The reason why we have so many of them is because they have a few incredibly important functions critical to our life.

Notice the characteristic donut-shape.

Cornwallite, conicalcite and other minerals from the Reconquistada prospect, Dolores mine, Pastrana, Mazarrón, Murcia

The “Reconquistada” claim is made up of small extractive mining works near the “Dolores” iron mine, in the municipality of Pastrana (Murcia, Spain). In this area there are various exploitations that benefited copper ores. In the case of the “Reconquistada” mineral species, the presence of arsenic in the mineral composition made copper extraction difficult.

From a scientific point of view, these mining works have been important due to the numerous species found. Three of them were identified for the first time worldwide in this mines: barahonaite-(Fe), barahonaite-(Al) and cobaltarthurite (Jambor et al., 2002; Viñals et al., 2008).

But there are other interesting and very colourful minerals. Two of them are very similar in appearance, but distinguishable under magnification: cornwallite and conichalcite. Both are copper arsenates, but conichalcite contains calcium. Cornwallite appears as spherical globules, with a smooth and very brilliant surface, usually with a lighter green color than conichalcite. Conichalcite tends to have a rough surface and a more intense colour.

In this specimen of the photograph, various botryoidal aggregates of conichalcite could be observed, with the characteristics described before, together with an isolated sphere of cornwallite. They are disposed on a matrix with yukonite (an iron and calcium arsenate).

Globular aggregates of conichalcite with internal radiated crystals

Spicules bring light

Sponges, like all animals, possess some sort of a skeleton that gives their bodies shape. As a whole, poriferans have diverse skeletal elements including calcareous laminae, organic filaments, and siliceous and calcareous spicules. The skeletons of each of the major poriferan groups are distinctive and have been used to reconstruct their evolutionary relationships.

This is a second brief publication about spicules, but this image is completely different however; here the darkfield technique has been adapted, using a turret condenser.