Marine Algae are organisms that are able to carry out the process of photosynthesis; using energy provided by the sun light. These plants live in aquatic environments , mainly in the sea; but some species can be found in freshwater. It all depends on the species.
They can be unicellular or multicellular, and they are eukaryotic organisms; which means their cells have a cytoplasm.
According to investigations, these organisms were the first vegetables that existed , taking into account all their evolutive process .
There is a wide variety of species, types ,and groups of marine algae, which have different characteristics. So their size, color, habitat, nutrition and even reproduction, are quite variable. Now, since algae are highly recommended for human consumption nowadays, we invite yoy to read all the information we have for you.
Table Of Content
Main Characteristics Of Marine Algae:
Following, you will find the most outstanding characteristics of these plants, which have become really popular and useful in recent years.
Nutrition
Algae are mainly autotrophic organisms , which means they can synthetize all the required substances for their metabolism. Although there are cases in which algae, also have the capacity to feed themselves in an heterotrophic way. This means they need of others organisms.
It should be noted that they play a fundamental role in the aquatic ecosystem, since they are the main primary producers. This is to say, they are the base of the food chain that supports many species of marine animals.
Now, the algae don’t take their nutrients from the soil on which they are fixed. These organisms feed themselves, from the nutrients provided by the liquid environment where they live, thus the nature of their food varies, according to whether they have chlorophyll or not.
Then, the process that takes place in marine algae that have chlorophyll; is to decompose the carbonic acid that is dissolved in the water. They carry out this process, using light rays provided by the sun. In contrast, in the case of algae that don’t have chlorophyll, , they feed from beings of their marine environment, such as animals and fungi. In these cases, it should be noted that many algae live parasitically on the bodies of other animals or plants.
Another important aspect to understand this process, is that algae don’t metabolize nutrients by circulation; all this is carried out by means of cell-to-cell absorption. This is the reason why if we find algae outside the water, the upper part will be dry. The lower portion of their structure, which is in contact with water, remains healthy.
According to several studies, each species of algae are placed at specifics depths. This location is determined by their sun light, pressure and temperature requirements, to develop the process of photosynthesis. Thus, algae never leave, their ideal depth.
Size
There are more than 30,000 species of algae, with their corresponding characteristics of size. It can range from microscopic to giants species, which measure about one hundred meters. Given the high number of algae species, we will find many differences between each one of them. There are unicellular and microscopic species, as well as colonial species, that have the ability to develop complex anatomies. Therefore , it’s a complex task, to list the characteristics of every algae according to their specific size, since there are many differences among each species.
Color
The characteristic color is quite varying, among every species; since it depends on the pigments located in the plastids . So, chlorophyll for example is green, the phycoerythrin is red, the fucoxanthin is brown, carotene is orange, phycocyanin provides blue color and finally zeaxanthin is yellow. Then according to each species, and its particular pigments, its final color will be determined
Clasification of Marine Algae
To explain about the classification of marine algae, it is necessary to mention that they constitute a polyphyletic group. This means it is constituted by the artificial union of scattered branches of the evolutionary tree.
Then, to understand their classification , we proceed to take into account their pigments, in conjunction with the substances they have in reserve. Their characteristic cell wall and cell division, are also considered. According to these aspects, it can be said that there are prokaryotic autotrophic algae and eukaryotic algae.
Prokaryotic Autotrophic Algae
This group is comprised by Cyanobacteria , which belongs to the sort of bacteria. These algae are photosynthetic and have chlorophyll, as well as phycobilins as an auxiliary pigment. This group was commonly denominated by 
scientists as “cyanophyte” or «blue-green algae«, but today this term is limited to algae, in the case of eukaryotes. The expression of blue-green algae has been considered as obsolete, and its use is therefore dismissed. All this, since the difference between an eukaryotic cell and a prokaryotic one was discovered , so it confirmed that these were the unique prokaryotic algae. ( the cyanobacterias).
Eucaryotic Algae
This type of marine algae, is included within the Protist Kingdom or classification. These organisms are photosynthetic autotrophic beings; since they have the capacity to create organic matter, employing light energy and inorganic matter. Therefore, they are usually considered as plants in some classification systems.
It is important to mention that this type of marine algae, can be unicellular or multicellular. They have a cell wall that is formed by cellulose molecules; which is their main characteristic. In the case of some multicellular specimens, cells are organized into tissues. In turn, the structure already formed is called talus.
According to many specialists , the most common definition that can be attributed to these marine algae, is » photosynthesizes eukaryotic organisms ,by chlorophyll associated with other pigments located in the chloroplasts, which reproduce by spores or gametes, produced in sporocysts or gametocysts . They live in the water or in very humid environments»
We invite to watch this video, so you can learn interesting things about algae
Most Common Types of Marine Algae
As youl will note following, algae are classified according to their distinctive color, so their pigments willl be the main aspect…
Green Algae
This group has about 10,000 different species, being undoubtedly a very diverse group . In turn, they are related to terrestrial plants. Although they can be found in the sea, these algae are actually more common in freshwater, covering a wide variety of habitats. Only 10% of the species that make up this group are found in salty waters. On the other hand, those that live in the sea, are located where the rays of the sun can arrive, so that they can carry out the photosynthesis ,as well as the processes of nutrition and development.
Most of these species are unicellular, mostly flagellated, but there are also cases, where they develop basic pluricellular structures. It’s important to mention that they are often related to the terrestrial plants, since they are very similar. This is due to the presence of pigments like chlorophyll, in addition to carotene and xanthophylls. They also have starch as their reserve substance
It is also known that these species of algae ,can be found in habitats of very adverse situations. They can even develop in the air, in very humid environments. Most of the species in this group are benthic, meaning they are linked to the bottom of the surface; but there are also cases where they are planktonic, which means they can live in suspension.
Regarding their reproduction, they are able to reproduce asexually, by means of mobile spores. Although there are cases, when they also reproduce sexually, through the fertilization of an oosphere , which is the female gamete, by a male gamete frequently flagellated, which is the spermatozoon .
Red Algae
This group of red algae is as important as the previous one. About 7000 species make up it , with a wide range of shapes and sizes. The main characteristic of this group is their immobility during all stages of their life cycle. This is because they don’t have flagella.
Their plastids contain two membranes, chlorophyll, al well as accessories pigments of carotenoids and phycobiliproteins. These last two pigments hide the color of chlorophyll and result the distinctive red color of this species. Moreover, these algae are mainly located in deep waters.
Note that most of the species of this group live in the sea, and only 164 species live in fresh water. The habitats and the ecosystems where they develop, go from intertidal areas to even very deep waters, all this depends on the transparency of the water. So, red algae can live at depths that range from 100 meters to 250 meters.
Finally the obvious conclusion is that the algae of this group , are the most abundant in depths. This is because their pigments give them the ability to capture, the wavelengths of the sun’s rays that penetrate deeper into the water.
Glaucophytic Algae
This is a small group of algae that is made up of about 13 species, all of them unicellular beings, which is its main characteristic. On the other hand this group of glaucophytic algae, are characterized by the presence of “cianelas”, that is to say the plasts that perform the photosynthetic function, as in the case cyanobacteria, and the absence of chloroplasts. The reproduction of these algae is not sexual , but rather it is carried out through bipartition.
Brown Algae
These algae belong to the kingdom of Protists, with approximately 265 genres of about 2000 species, mostly seaweed. Only six genres of this group inhabit in freshwater. It is important to mention that this group of brown algae are considered as the main primary producers, forming the basis of a food chain; that is made up of several species of animals within their ecosystem.
In relation to their habitat, brown algae are mostly located on rocky shores of temperate zones, even in sub polar areas. So they predominate in intertidal zone as is the case of the “Fucales” and «Laminarials» The brown algae, can reach up to 60 meters length, and they float in the water freely , which are also outstanding characteristics.
On the other hand, it must be taken into account that brown algae have pluricellular forms with differentiated tissues between different species and genera. In general terms, it is known that they have pigments like chlorophylls and also fucoxanthin, this results in their characteristic brown color 
Regarding to the shapes and sizes, there is a wide variety in this species. There are very small members in this group that consist of only a few cells, therefore microscopic algae are formed. Others members grow not a little more than a few centimeters long.
Other groups of brown algae , grow to sizes much larger than the previous mentioned, for example, kelp algae which are usually the most visible algae in their respective habitats. So, their size can vary from 50 centimeters to 60 meters, which is the largest known size. This corresponds to the giant algae species of Macrocystis pyrifera. There are also different shapes, depending on each individual of this specie . We can find from subtle strands of cells to wide and rigorous branches.
The visible structure of brown algae is known as thallus.
It is important to highlight, that they are the largest seaweed that exist. They also grow very fast. This growth usually happens diffusely, since the reproduction of the cells can be carried out in any part of the thallus.
Golden Algae
This group is made up of at least 1000 species, which are generally flagellated unicellular organisms, although many of these species form very elaborated colonies. Golden Algae live mainly in freshwater, but they can also be found in moist soil and even in the sea. In general, it’s very common to see them in lakes and lagoons that have clean, fresh and above all cold water.
In terms of nutrition, most of these algae are photosynthetic, although there are also cases of mixotrophs and heterotrophs. They have the ability to change photosynthesis by a heterotrophic lifestyle , when necessary. In this way, they can develop pseudopods in order to catch food, which is usually based on small protists.
Regarding their structure, these algae present a wide variety in terms of morphology. Most of them are unicellular beings, but they also have the capacity to group themselves in colonies, and in this wayconstitute a more common structure with a branched stem. It is known that their reproduction can be sexual or asexual.
Green-Yellow Algae
This small group of algae consists of about 600 species, these can be found mainly in continental waters and soil, although some species are also marine. Some of the species are unicellular and others can be grouped into colonies.
Regarding their structure, green-yellow algae can occur in unicellular and sometimes flagellated forms. Although these species usually tend to group in filament colonies that can be simple or branched. They can also be found in palmeloid states. It should be noted that they don’t form mobile colonies, but flatulent gametes or zoospores may also appear
Benefits of Marine Algae
It has been shown that algae provide great benefits to the people who consume them. Thanks to discoveries, of studies developed in places where they are consumed in big amounts; it was demonstrated that people get to live longer in a healthy way.
We show following , the main benefits that can be highlighted: they are completely remineralizing, this positively influences the health of bones and helps the general biochemical functionality of the organism. In addition, marine algae can stimulate the proper functioning of the thyroid gland; for this reason the metabolism is improved. Although, people suffering from problems with these glands , should avoid their consumption without specialized supervision.
These amazing plants also have alkalizing properties, which certainly help compensate the acidosis, caused by excess in the consumption of red meats or highly processed foods. We must also mention, that they have depurative properties, since they help to clean the blood. Their capability to stimulate the correct functioning of organs, such as kidneys and liver, and to eliminate toxins that may be present in food, is also remarkable.
But that’s not all, since marine algae also have positive effects on the physical aspect. It has been confirmed that their consumption improves the skin, hair and nails; keeping them in a healthy state. We could mention for example diatoms algae . Marine algae are also useful to lose weight and to eliminate fat concentrations; even mucus deposits that can be created by excess of milk consumption.
Main properties of Marine Algae
Marine and freshwater algae, have many beneficial properties, that should be noted. They are considered as the oldest plants in the world, which make them rich in vitamins and minerals. This is their main advantage, when comparing them with other vegetables.
In addition, we should mention that compared to fish, algae don’t absorb too much pollution; because if they are in a polluted habitat, they simply don´t grow or develop. Therefore, they can be considered as an organic and clean source of the main nutrients.
All species of marine algae are considered to be rich in iron and calcium; they are listed as one of the richest vegetables regarding these minerals; which is probably their main benefit. They are also known for having significant amounts of magnesium and potassium.
They also contain alginic acid, which according to several studies contributes to eliminate naturally, some toxins and heavy metals outside the body. In addition to these important contributions, they are also rich in vitamins, specifically in vitamin A, group B (except vitamin B12), also C, D, E and K. Their content of proteins and carbohydrates, is quite significative.
We give you this video, for you to learn about the Uses of Algae:
Preparing Marine Algae For Consumption
First of all we must say that all algae are edible; so every person can select the more pleasant alga, according to his likes. You shoul also know, that all algae are sold already dries; this certainly facilitates their storage and their posterior use, since it is recommended to preserve them in this form. They can be stored and conserved in this state, for long periods of time without losing their main properties.
Algae are not usually sold in traditional supermarkets; so you can find them in specialized places, such as organic stores. Among the most common ones for consumption, we can mention wakame, kombu, arame, as well as nori, dulse, hiziki and agar-agar.
Before preparing the algae , it is necessary to soak them , in most cases a few minutes will be enough. Depending on the species and type, they should also be cooked. It is important to know, that once algae have been purchased; the best way to preserve them before being used, is in a sealed tight container.
Another aspect you should consider before buying algae, is that once they have been soaked they usually grow considerably. Once you become familiar to different types of algae , you could buy the proper amounts, according to your needs. Howerver before this happens, the best thing is to buy small quantities. Finally it is very important that before soaking the algae, you should wash them thoroughly with plenty of cold water.
Seaweed are usually included in dishes such as salads, soups, even stews. Although there are many others ways to include them in recipe preparations, these meals must be the first options for beginners . Their consumption usually depends on the particular likes of every person. The nori seaweed is usually taken into account, since it is quite used for preparing Sushi….