Seaweeds are present all over the world and grow in all bodies of water or in any terrestrial environment where the humidity level remains high. Some species can even survive on snow or ice in polar or mountainous regions, or withstand the high temperatures of hot springs.
They are an important source of essential nutrients, including proteins (very abundant in spirulina). They are mostly rich in iodine, which the thyroid needs to secrete hormones governing different metabolisms in the body of humans. Seaweed also contains relatively considerable amounts of fiber. These are known for their ability to lower cholesterol and glucose levels in the blood.
The liveliness of their colors, the elegance of their forms, have always made them sought after by people of the world who prepare excellent dishes.
Coastal seaweeds can be divided into three main classes according to their color:
Pheophyceae for brown algae,
Chlorophyceae for green algae,
Rhodophyceae for red algae.
Seaweeds come in a number of different forms, from the single-celled type to branched filaments. These colors correspond to the presence of different photosynthetic pigments. Green is the color of chlorophyll, a pigment found in all plants and whose role is to transform the sun’s energy to achieve photosynthesis. Brown and red, for their part, come from extra pigments which have the role of capturing the energy of the sun and directing it towards the chlorophyll.
They are also classified into a dozen subclasses depending on their coloring and whether they have starch or not.
Their vegetative apparatus is called a thallus. A word of Latin origin which means “flattened”. The absence of conducting vessels also explains their rather modest size. They have a vegetative apparatus of simple structure, that is to say presenting a little developed level of cellular differentiation and, in principle, devoid of specialized organs.
Having no roots, seaweeds cannot become anchored in mud or sand. The thallus attach itself to solid substrates using discs or spikes.
They are thus found in great abundance on rocky coastlines.
Seaweeds support a diverse microfauna and microflora, protect countless species from predators, filter out too bright light, break wave energy, and protect animals from drought at low tide. In short, the presence of seaweeds generates a more complex spatial structure where several species find their ecological niche, that is to say their living space.
I Hope that these lines whet your curiosity.