Meanings of Dimorphism

According to abbreviationfinder, the notion of dimorphism is used in the field of biology to name the condition of those species of animals or plants that exhibit two anatomical aspects or two different shapes. It is possible, in this sense, to distinguish between different types of dimorphisms.

Sexual dimorphism is characterized by variations in physiognomy between males and females, and this is usually present in most species, although to different degrees.

In the case of reptiles, insects, and spiders, for example, the females are usually larger than the males. The opposite occurs with mammals, a group where males can reach a size much larger than that exhibited by females.

Deer (the male has antlers and the female does not) and lions (the male stands out for his mane) are two animals with clear sexual dimorphism. Even in humans, sexual dimorphism is evident, since the sexual organs of men are manifested externally, while women have marked mammary glands.

Generational dimorphism (the alternation of different forms of reproduction in the same species), seasonal dimorphism (changes in the color of the plumage of birds according to the reproductive season) and ecological dimorphism (alterations according to the relationship with the environment or habits) are other types of dimorphisms noted by biology.

Cerebral sexual dimorphism, for its part, deals with the differences that can be seen in the brain of males and females of the same species, taking into account morphological and functional aspects. With respect to our own species, the many studies carried out have shown that the brain of man is larger than that of women at a volumetric level, although this does not have any repercussion on his intelligence.

For geology, dimorphism is the condition of that substance that can crystallize in two different systems.

Fungal dimorphism

Also called dimorphism in fungi, fungal dimorphism is a reversible phenomenon whereby a fungus can change its shape from a mycelial to a yeast-like.

The mycelium is the mass of cylindrical filamentary elements (hyphae) found in most fungi and constitutes their vegetative body. Yeast, on the other hand, is the name given to any unicellular microscopic fungus with the ability to carry out decomposition through the fermentation of various organic bodies, especially carbohydrates and sugars, giving rise to various substances.

The dimorphism causes the fungi to proliferate in the form of yeasts or large spherical structures in the tissues, although at room temperature they take on filamentous forms. Dimorphic fungi include the organisms that cause sporotrichosis, blastomycosis, histoplasmosis, paracoccidiomycosis, and coccidiomycosis.

A fungus can present dimorphism depending on:

* temperature: occurs with Penicillium marneffei, which changes shape at different temperatures, although without changing the medium. It can change from being stringy (when the temperature is between 25 and 28 °C) to yeast-like (between 37 and 37 °C);

* nutrients: can be seen in Candida albicans, which has a yeast-like form in rich culture media and a filamentous form in poor media. The yeast form is consistent in the way it reproduces and changes in the environment radically influence its morphology;

* temperature and nutrients: in this case of dimorphism the two points just exposed are combined and can be seen in Histoplasma capsulatum, Sporothrix schenckii, Blastomyces dermatitides and Paracoccidioides brasiliensis.


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