3 types of algae. Types of algae, their benefits for humans and applications

The world's oceans are an endless source of amazing animals and plants, among which various algae occupy an important place. The report will focus on a representative of marine flora - brown algae.

Types of brown algae

Brown seaweed - multicellular organisms. They live in sea water at depths from 5 to 100 meters. They usually attach to rocks. Brown color gives algae a special brown pigment. Some types of algae are striking in their size, reaching a length of up to 60 meters; there are also very tiny representatives. Lives in the world's oceans more than 1000 species brown-green algae.

From the broad class of brown algae, several interesting and useful species can be distinguished.

1. Sargassy

The Sargasso Sea got its name from the accumulation of floating brown seaweed in its waters. - sargassum. Huge masses of these algae float on the surface of the water and form a continuous carpet. Because of this feature of brown algae, in ancient times the Sargasso Sea had a bad reputation - it was believed that a ship could become entangled in algae and would not be able to sail further, and if sailors climbed into the water to untangle the ship, they would become entangled and drown themselves.

In fact, the legends and myths about the Sargasso Sea are not true, because the sargasso is absolutely safe and does not interfere with the movement of ships.

Sargassum is used:

as a source of potassium;
the stems of these algae provide food and shelter for their young.

2. Fucus

Other names: sea grapes, king algae. Fucus is distributed in almost all marine bodies of water on Earth. It lives at shallow depths in the form of small bushes with long greenish-brown leaves. Fucus is a storehouse of vitamins and useful substances.

Used:

in medicine for the treatment and prevention of various diseases and strengthening the immune system;
helps care for skin and hair, and is used as a weight loss supplement.

3. Kelp

Another name for kelp is sea kale. It looks like a long stem of brown-green color with leaves. This algae lives in the Black, Red, Japanese and other seas. The chemical composition of algae is rich in vitamins, minerals, and amino acids. Consumed as food There are only 2 types of kelp - Japanese and sugary.

Usage:

Inedible varieties are widely used in medicine.
Like fucus, kelp is used in various diets as a natural appetite suppressant.
Laminaria contains special substances that can protect the human body from dangerous radiation exposure.
Sea kale is also used to treat cancer and leukemia.

With constant consumption of kelp, you can reduce cholesterol levels in the blood, improve intestinal function, increase the protective properties of the immune system, normalize metabolism, and improve the functioning of the nervous, circulatory and respiratory systems.

Brown algae - sea plants, which are widely used in many areas of human activity.

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Algae play a huge role in nature and human life. Firstly, they are active participants in the cycle of substances in natural environment(the simplest unicellular species).

Secondly, irreplaceable natural sources vital microelements (vitamins, minerals). They are also used in medicine, cosmetology, Food Industry and other industries.

Their breeding does not require difficult conditions, and they grow at a depth of several meters to 40-100.

The life cycles of algae have several stages, depending on the complexity of the structure. The same goes for the ability to reproduce.

What species, groups, names exist, in which sea is algae farming carried out, photographs, etc. interesting information- about this in this article.

Description

Algae, unlike plants, grow in aquatic environment(although there are also plants that live in similar environments). There are also soil and rocky representatives.

Life in water has relative stability: the presence of liquid, constant light and temperature, as well as a number of other advantages. And as a consequence, every cell that is integral part algae, identical to the others. Therefore, these aquatic “plants” (conventional name) practically do not have any pronounced features in their appearance(except for some, more “highly developed”).

Mostly algae live in coastal areas of the seas - rocky shores, less often - sand or pebbles. Max Height, on which these aquatic “plants” can live - surfaces slightly wetted by sea drops (an example of almost planktonic ones is sargassum), the minimum is several meters deep (an example of deep-sea ones - red ones).

There are algae that live in tidal pools of rocky surfaces. But such varieties of marine inhabitants must withstand the lack of moisture, variable temperature and degree of salinity.

Algae are used in medicine, agronomy (soil fertilization), human food production, industry, and so on.

Body

Algae in their structure consist of one or many cells.

This one system, which is cells of the same type layered on top of each other. There may be dissection here, but the presence of vegetative organs and other parts of the body of this aquatic “plant” is excluded.

The appearance of algae is somewhat similar to terrestrial non-woody plants.

The body of the algae consists of:

thallus (thallus);
trunk (may or may not be present);
grips (for fastening to surfaces - rocks, bottom, other similar plants);
trailers.

Types of algae

There is a huge number - from single-celled to complex (reminiscent higher plants). They also come in different sizes - huge (up to 60 meters) and microscopic.

In total there are about 30,000 species of algae. They are divided into the following departments:

blue-eyed;
prochlorophytes;
cryptophytes;
red;
golden;
dinophytes;
diatoms;
brown;
green;
yellow-green;
euglena;
characeae.

The division is also carried out into the following groups of algae (according to the degree of complexity of the structure):

amoeba-like (examples: golden, yellow-green, pyrophytic);
with a monad structure - unicellular, move thanks to flagella, some have an intracellular primitive structure (examples of algae: green, yellow-green, golden, euglenic, pyrophytic);
with a coccoid structure - unicellular, without any organelles, form colonies;
with a palmelloid structure - a combination of several coccoids in total weight, have big sizes, attach to the substrate;
with a filamentous structure - these are already transitional from unicellular to multicellular algae, outwardly similar to a branched thread;
with a lamellar structure - multicellular, which are formed from filaments that are combined with subsequent layering in different planes, forming plates (there are single-layer and multilayer);
with a siphonal structure - consist of a multinucleated giant cell, similar to branching threads and balls.

Titles and photos

Types of algae in the images:

Unicellular - consist of a cell, a nucleus and flagella (trailers). They can only be seen under a microscope.
Multicellular - kelp, which is known to man under the name “sea kale”.

Life cycle

In algae, development occurs according to a cycle or cyclomorphosis (this depends on the complexity of the structure of the aquatic “plant” and, accordingly, the method of reproduction).

Algae that do not have (or have exceptional cases) the ability to sexually reproduce; due to development, only the structure of the body changes. The concept of cyclomorphosis is applicable to such aquatic plants (examples of algae: hyella, blue-green, glenodinium).

Cyclomorphosis is characterized by a high degree of plasticity. The passage of stages depends largely on the environmental conditions of the environment. The manifestation of strictly all stages of cyclomorphosis does not always occur; some may even “fall out” of the general sequence.

Strict passage of all stages of the life cycle of algae (in the diagram above) occurs exclusively in those aquatic plants that occupy the upper stage of evolution (for example, brown ones).

Brown algae

These are multicellular aquatic “plants” that belong to the ochrophytes. The name comes from the color of the pigment substance contained in the chromatophores: green (which means the ability to photosynthesize), as well as yellow, orange and brown, which, when mixed, form a brownish tint.

They grow at depths of 6-15 and 40-100 meters in all marine reservoirs of the globe.

Brown algae, compared to others, have a more complex structure: they have similar organs and various tissues in their body.

The surfaces of cells consist of a cellulose-gelatinous substance, which contains proteins, salts, and carbohydrates.

Each algal cell contains a nucleus, chloroplasts (in the form of disks), and a nutrient (polysaccharide).

Life cycle of brown algae

This group of aquatic “plants” has several types of growth: through the apex or by cell division.

Brown sexually and asexually. This means that some of them are recreated by fragmenting their body (thallus), forming so-called buds or through spores.

Zoospores have flagella and are motile. They also produce a gametophyte, through which sex cells are formed.

There are gametes obtained from the sporophyte and having eggs and sperm in the haploid stage.

And these aquatic “plants” emit pheromones, which promotes the “meeting” of male and female reproductive cells.

Thanks to all these processes, alternations of generations occur in brown algae.

Uses of brown algae

The most popular representative of this group is kelp, or “sea kale”. This algae grows along the shores, forming thickets. Laminaria contains a fairly large number of macro- and microelements vital for humans, the most important of which is iodine. Besides food, it is also used as soil fertilizer.

Brown algae is also used in medicine and in the manufacture of cosmetics.

Characteristics of unicellular algae

These varieties of aquatic “plants” are an independent system that is capable of growing and developing, as well as self-reproducing.

In size, these are microscopic algae (not visible to the naked eye), which in essence can be considered a “factory” for the extraction of useful raw materials: through the process of absorption from environment carbon dioxide and mineral salts, with their subsequent processing into proteins, fats and carbohydrates.

The life support products of unicellular algae are oxygen and carbon dioxide, which allows them to be active participants in the natural cycle.

Algae farming

In which sea is the most widespread cultivation of these marine “plants”? According to reference data, maximum amount algae is found in the White Sea. On the shore there is the village of Rebolda (in the area of Solovetsky Island), where they extract and store these water gifts.

There are 2 types of brown algae: the famous kelp and fucus (“sea grapes”).

In addition to being eaten, these “plants” are used to produce biologically active substances that are used in medicine. These are very useful preparations, since they contain environmentally friendly algae from the White Sea.

Such products lower blood cholesterol levels, improve the functioning of the thyroid gland, prevent the development of age-related diseases associated with blood vessels, and so on. “Sea grapes” is good to use for problems with varicose veins veins, cellulite, the appearance of wrinkles.

Role in nature and human life

Algae are studied by a specialized science - algology (or phycology), which is a branch of botany.

Collecting information about these aquatic “plants” is necessary to solve such important problems: general biological problems; economic tasks and so on.

This science is developing in the following areas:

Use of algae in medicine.
Use in solving environmental issues.
Accumulation of information about algae in order to solve other problems.

These marine “plants” currently both live in natural reservoirs and are grown on special farms.

Seaweed, as food and more, is popular in many countries of the world: Indonesia (annual harvest 3-10 million tons), Philippines, Japan, China, Korea, Thailand, Taiwan, Cambodia, Vietnam, Peru, Chile, England, USA ( California) and others.
A new food product has now been discovered in the Philippines - seaweed noodles (contains calcium, magnesium, iodine).
The beloved Japanese nori seaweed, which is dried in leaves and looks like square thin plates, is used in making sushi, rolls, and soups.
In Wales, a popular lawer bread is made from oats and red laver seaweed.
Made from seaweed food gelatin, additives, alginates (dressing materials, used in dentistry).
Agar produced from these aquatic “plants” is used in the preparation of confectionery, desserts, drinks, and meat dishes.
Algae concentrates are used in preparations to get rid of excess weight. Also included in toothpastes, cosmetics and paints.
Alginates are used in industry (paper coatings, paints, gels, glue, textile printing).

Summary

The types of algae discussed in the article (with photos), names, groups, cultivation and application only indicate that these are truly important components not only of nature, but also of many aspects of human life (health, beauty, industrial raw materials, food, and so on) . Without them there would be no proverbial" seaweed", marmalade, sushi and other such familiar dishes.

At first glance it may seem that these simple natural “plants” are primitive (in their structure, life cycle) algae, but in reality everything is different. It turns out that even these aquatic “plants” have sexual reproduction, emit pheromones and support the circulation of substances in nature.

Algae report will tell you what kind of algae there are, and what the role of algae is in nature and human life.

Algae message

Almost every body of water contains algae. They are a wayward indicator of water purity and supply it with oxygen useful for all aquatic inhabitants.

What is algae?

Algae belong to an ecological heterogeneous group of multicellular phototrophic, unicellular and colonial organisms that, as a rule, live in water bodies. All known species algae are united among themselves by the following signs:

1. characterized by photoautotrophic nutrition and the presence of chlorophyll

2. there is no differentiation of the plant body into organs as such

3. algae have a pronounced conducting system

4. live in humid environments

5. no integumentary membrane

Due to the fact that algae are adapted to an aquatic environment, they have developed a special feature of physiology - the necessary nutrients are absorbed by the entire surface of the plant’s body. The vital activity of algae depends on four factors - light, carbon dioxide, chemical composition water and its temperature.

What types of algae are there?

In nature, algae comes in three main types:

* Green algae

They belong to the division of lower plants, which have different morphological structures and sizes. They contain carotenoids and chlorophyll plates. Green algae come in multicellular and unicellular forms. Have reserve substance– starch, sometimes oils. It is noteworthy that unicellular green algae live not only in the aquatic environment, but also in soil or snow. But multicellular plants live in upper layers reservoirs, which is due to the implementation of the productive process of photosynthesis.

* Brown algae

They belong to the division of ochrophytic algae. Modern biology There are more than 2000 species of them. Almost all brown algae live in marine aquatic environments. And only 6 species of these plants were able to adapt to life on dry land during evolution. Scientists have discovered that the chromatophores of brown algae contain fucoxanthin, a special pigment that colors them brown.

The most common brown algae are: Macrocystis Laminaria and Cystoseira. There is practically no chlorophyll in their body, which makes the life activity of these algae independent of photosynthesis processes. Therefore, the habitat of plants is the seabed.

* Red algae

Red algae belong to a group of algae that contain a specific red pigment in their body - phycoerythrin. Their color depends on the amount of phycoerythrin in the plant’s body - it ranges in color from bright pink to dark cherry color.

Red algae primarily live in the seas. Their body carries out photosynthesis, despite a small amount of chlorophyll. These plants were found wide application V industrial production, most of them are suitable for consumption.

A message about the importance of algae in nature and human life

1. Algae are the basis of nutrition for herbivorous animals, such as crustaceans, mollusks, some fish, mammals and others.

2. Algae enrich the water column and the air above it with oxygen. Dead plants of some species are capable of forming sedimentary rocks: diatomite, limestone and tripoli. They contribute to the process of soil formation and increase soil fertility. Algae that live in the bottom area provide shelter and home for fish and other aquatic animals.

3. Algae are consumed by humans as food. Bromine, iodine, agar-agar are also extracted from them, and medications are made.

4. They are used for biological treatment water and act as fertilizer.

5.Algae is widely used in chemical, food, paper and textile industries industry.

Besides useful properties, some types of algae also cause harm. For example, unicellular algae, multiplying en masse in fresh water bodies, lead to water blooms. Living in airlocks and water filters, they interfere with their normal operation.

We hope the information provided about algae has helped you. And you can leave your story about algae using the comment form.

Seaweed(lat. Algae) - heterogeneous environmental group predominantly phototrophic unicellular, colonial or multicellular organisms, usually living in an aquatic environment, systematically representing a collection of many departments. Entering into symbiosis with fungi, these organisms, in the course of evolution, formed completely new organisms - lichens.

The study of algae is important stage in training specialists in the field of mariculture, fish farming and marine ecology. The science of algae is called algology.

Seaweed- a group of organisms of different origins, united by the following characteristics: the presence of chlorophyll and photoautotrophic nutrition; in multicellular organisms - lack of clear differentiation of the body (called thallus, or thallus) into organs; lack of a pronounced conduction system; living in an aquatic environment or in damp conditions (in soil, damp places, etc.). They themselves do not have organs, tissues and lack a covering membrane.

Some algae are capable of heterotrophy (feeding on ready-made organic matter), both osmotrophy (on the cell surface), for example flagellates, and by ingestion through the cell mouth (euglena, dinophytes). The size of algae ranges from fractions of a micron (coccolithophores and some diatoms) to 30-50 m (brown algae - kelp, macrocystis, sargassum). Thallus can be either unicellular or multicellular. Among multicellular algae Along with large ones, there are microscopic ones (for example, sporophyte of Laminariaceae). Among unicellular organisms there are colonial forms, when individual cells are closely related to each other (connected through plasmodesmata or immersed in common mucus).

Algae include a varying number (depending on the classification) of eukaryotic divisions, many of which are not related common origin. Also often referred to as algae blue-green algae or cyanobacteria, which are prokaryotes. Traditionally, algae are classified as plants.

Algal cells (with the exception of the amoeboid type) are covered with a cell wall and/or cell membrane. The wall is located on the outside of the cell membrane and usually contains structural component(eg cellulose) and amorphous matrix (eg pectin or agar substances); it may also have additional layers (for example, the sporopollenin layer in chlorella). The cell membrane is either an external silicone shell (in diatoms and some other ochrophytes), or a compacted upper layer of cytoplasm (plasmalemma), in which there may be additional structures, for example, vesicles, empty or with cellulose plates (a kind of shell, theca, in dinoflagellates ). If the cell membrane is plastic, the cell may be capable of so-called metabolic movement - sliding due to small change body shapes.

Photosynthetic (and “masking” them) pigments are located in special plastids - chloroplasts. A chloroplast has two (red, green, charophyte algae), three (euglena, dinoflagellates) or four (ochrophyte algae) membranes. It also has its own highly reduced genetic apparatus, which suggests its symbiogenesis (origin from a captured prokaryotic or, in heterokont algae, eukaryotic cell). The inner membrane protrudes inward, forming folds - thylakoids, collected in stacks - grana: monothylakoid in red and blue-green, two or more in green and charoves, trithylakoid in the rest. The thylakoids, in fact, are where the pigments are located. Chloroplasts in algae have different shapes (small disc-shaped, spiral-shaped, cup-shaped, star-shaped, etc.). Many chloroplasts have dense structures called pyrenoids.

Products of photosynthesis, in this moment excess, are stored in the form of various reserve substances: starch, glycogen, other polysaccharides, lipids. Among other things, lipids, being lighter than water, allow planktonic diatoms with their heavy shells to stay afloat. Gas bubbles form in some algae, which also provide lifting force to the algae.

Algae have vegetative, asexual and sexual reproduction.

Large seaweeds, mainly brown ones, often form entire underwater forests. Most algae live from the surface of the water to a depth of 20-40 m; isolated species (red and brown) with good water transparency go down to 200 m.

In 1984, coralline red algae was found at a depth of 268 m, which is a record for photosynthetic organisms. Algae are often large quantities live on the surface and in the upper layers of the soil, some of them assimilate atmospheric nitrogen, others have adapted to life on the bark of trees, fences, walls of houses, and rocks.

Microscopic algae cause red or yellow "coloring" of snow in high mountains and polar regions. Some algae enter into symbiotic relationships with fungi (lichens) and animals.

Algae are an extremely heterogeneous group of organisms, numbering about 100 thousand (and according to some data up to 100 thousand species only within the diatom division) species. Based on differences in the set of pigments, the structure of the chromatophore, the characteristics of morphology and biochemistry (composition of cell membranes, types of reserve nutrients) most domestic taxonomists distinguish 11 divisions of algae.

Many useful substances used in the production of plastics, varnishes, paints, paper and even explosives are obtained from brown algae. They are used to make medicines (including iodine), fertilizers, and livestock feed. Algae occupy an important place in the menu of peoples South-East Asia, being the basis of many dishes.

The Red Sea is named so because of the abundance of oscillatorium - red algae. Although it contains a red pigment, it belongs to the blue-green algae division.

From the red algae eucheum, the substance carrageenan is extracted, which is necessary for making lipstick and... ice cream.

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Which have no stem, root or foliage. Preferential algae habitat are seas and fresh water bodies.

Green algae department.

Green algae there are unicellular And multicellular and contain chlorophyll. Green algae reproduce sexually and asexually. Green algae live in bodies of water (fresh and salty), in soil, on rocks and stones, and on the bark of trees. The Green Algae department has about 20,000 species and is divided into five classes:

1) Class protococcal- unicellular and multicellular flagellate forms.

2) Volvox class- the simplest unicellular algae that have flagella and are capable of organizing colonies.

3) Heat class- have a structure similar to that of horsetails.

4) Ulothrix class- have a filamentous or lamellar thallus.

5) Siphon class- a class of algae that is similar in appearance to other algae, but consists of a single cell with many nuclei. The size of siphon algae reaches 1 meter.

Department of red algae (purple algae).

Purples are found in warm seas at great depths. This department has about 4,000 species. Thallus red algae has a dissected structure; they are attached to the substrate using soles or rhizoid. Red algae plastids contain chlorophylls, carotenoids And phycobilins.

Another feature of red algae is that they reproduce using complex sexual process. Red algae spores and gametes motionless, as they do not have flagella. The fertilization process occurs passively through the transfer of male gametes to the female genitals.

Department of brown algae.

Brown algae- these are multicellular organisms that have a yellowish-brown color due to the concentration of carotene in the surface layers of cells. There are about 1.5 thousand species of brown algae, which have the most various shapes: bush-shaped, lamellar, spherical, crust-shaped, filamentous.

Due to the content of gas bubbles in the thalli of brown algae, most of them are able to maintain a vertical position. Thallus cells have differentiated functions: extinction and photosynthetic. Brown algae do not have a complete conducting system, but in the center of the thallus there are tissues that transport assimilation products. Nutrient minerals are absorbed by the entire surface of the thallus.

Different types of algae reproduce by all types of reproduction:

Sporov;

Sexual (isogamous, monogamous, heterogamous);

Vegetative (occurs when some parts of the thallus are accidentally divided).

The importance of algae for the biosphere.

Algae are the starting point of most food chains various bodies of water, oceans and seas. Algae also saturate the atmosphere with oxygen.

Seaweed actively are used to obtain various products: polysaccharides agar-agar and carrageenan, used in cooking and cosmetics, are extracted from red algae; alginic acids, also used in the food and cosmetics industries, are extracted from brown algae.