How long do algae live? Edible algae - types, benefits and harm. General characteristics of algae

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 asexual type reproduction. 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 are similar in appearance to other algae, but consist 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 are motionless because 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 a variety of shapes: bush-like, lamellar, spherical, crust-like, thread-like.

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.

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 by the following characteristics:

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 department of lower plants, which have different morphological structure and sizes. They contain carotenoids and chlorophyll plates. Green algae come in multicellular and unicellular forms. They have a 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 the small amount of chlorophyll. These plants are widely used in 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 water purification and act as fertilizer.

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

In addition to beneficial 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.

When treating with algae, brown marine species are most often used, for example, kelp, ascophylium, ampheltia, fucus, containing greatest number alginic acid. Many doctors insist on the benefits of algae in the treatment of cancer and diseases of the endocrine glands. Algae have also been used in cosmetology.

What is seaweed and how is it beneficial for humans?

Algae are a group of primarily aquatic, single-celled or colonial photosynthetic organisms. Unlike higher plants algae do not have stems, leaves, or roots; they form a protoplast. Contain a large range of useful substances.

The benefits of algae are known first-hand to adherents of alternative medicine. In particular, crushed or micronized algae are used in thalassotherapy: energy-rich substances penetrate the skin from the pulp, revitalizing metabolic processes and counteracting cellulite. In addition, the benefit of algae for humans is that they are rich in antioxidants: P-carotene, vitamins C and E, superoxide dismutase enzyme, microelements and are a source of essential fatty acids.

In total, there are more than 30 thousand species of seaweed - brown, green, red, blue-green and others. Treatment with seaweed is based on the fact that they contain large amounts of iodine, sea gum, plant mucus, chlorophyll, alginic acids, sodium salts, potassium, ammonium, and vitamins. Cosmetics mainly use extracts of brown algae - fucus, kelp, cystoseira. Speaking about the benefits of algae for humans, we must not forget that extracts obtained from individual species algae differ in their composition and therefore have a targeted effect.

Vitamins in sea and freshwater algae

The content of vitamins A, B1 in freshwater and seaweed is especially high; B2, C, E and D. Algae also contains a lot of fucoxanthin, iodine and sulfoamino acids. The importance of algae in human life is that they are able to stimulate and regenerate skin cells, have a softening and mild bactericidal effect. In others, moisturizing and water-retaining properties are clearly manifested due to the higher content of polysaccharides, organic acids, and mineral salts. Third, due to the active influence of organic iodine, fucosterol, mineral salts and vitamins, they are effective against cellulite, acne, and are beneficial for skin care. oily skin, since they provide regulation of fat metabolism and improve blood circulation.

In modern cosmetic practice, seaweed extracts are used in almost all types of skin and hair care products.

Main groups and features of algae, their classification

Speaking about the role of algae in human life, one cannot help but recall modern theory origins of life, which argues that bacteria were at the origins of all life on Earth. Later, some of them evolved, giving life to microorganisms containing chlorophyll. This is how the first algae appeared. Being recyclable solar energy and the release of oxygen molecules, they were able to take part in the formation of the shell of atmospheric oxygen surrounding our planet. Thus, those forms of life on Earth that are familiar to modern man became possible.

Classification of algae in the general development table is difficult. Plant organisms, dubbed “seaweeds,” are a highly arbitrary community of closely related organisms. Based on a number of characteristics, this community is usually divided into several groups. There are 11 main types of algae, and the difference between brown and green algae is more significant than the difference between green algae and higher plants such as grasses.

At the same time, all groups of algae have chlorophyll, a green pigment that is responsible for photosynthesis. Since only one of the groups of algae, green algae, has the same composition and ratio of pigments as higher plants, it is believed that they are the ancestors of forests.

In addition to green algae, there are blue-green, blue, red, and brown algae. But regardless of color, the entire huge number of species known to us, first of all, is divided into two large groups- unicellular and multicellular. Photos of the main types of algae are presented below on this page.

What are the main types of algae?

The main groups of algae include microscopic unicellular and large multicellular.

Microscopic unicellular algae are represented by one cell, which is capable of providing all the functions of the body. As can be seen in the photo, these algae have a size of several tens of microns (l micron is a thousandth of a millimeter). Most of them are adapted to a floating lifestyle. In addition, many species have one or more flagella, which make them very mobile.

The second main type of algae is large multicellular- consist of large quantity cells forming the so-called thallus, or thallus - what we perceive as an individual algae. The thallus consists of three parts:

• fixing apparatus - rhizoid, with the help of which the algae holds onto the substrate;
• stalk (legs), varying in length and diameter;
• plates cut into fibers in the form of strands or straps.

The dimensions of the thallus are very different, depending on the type of algae. For example, the thallus of the ulva, or sea lettuce (Ulva lactuca), does not exceed a few centimeters. The peculiarity of these algae is that their extremely thin plate can continue to develop and grow even after being torn off from the substrate. Some kelp specimens reach several meters in length. It is their thallus, clearly divided into three parts, that well illustrates the structure of macroalgae.

The shape of the thallus is also very diverse. There are known marine calcareous deposits consisting of algae of the genus lithothamnion (Lithothamnium calcareum), which during life looks like a small pink coral.

The role and importance of freshwater algae in human life

What types of algae are there, besides seaweed? The sea is not the only habitat for algae colonies. Fresh water ponds, small and big rivers is also their habitat. Algae live wherever there is enough light for photosynthesis.

So, even at great depths, near the bottom, seaweeds called benthic algae live. These are macroalgae that require solid support to establish and develop.

Numerous microscopic diatoms also live here, which are either located on the bottom or live on the thallus of large benthic algae. A huge number of marine microscopic algae form a significant part of the phytoplankton that drifts with the current. Seaweed can be found even in bodies of water with high salinity. Small algae, when multiplying, can color the water, as happens in the Red Sea due to the microscopic algae Thishodesmium, which contains a red pigment.

Freshwater algae are usually presented in fibrous forms and develop on the bottom of reservoirs, on rocks or on the surface of aquatic plants. Freshwater phytoplankton are widely known. These are microscopic unicellular algae that live in literally all layers of fresh water.

Freshwater algae have unexpectedly succeeded in colonizing other areas, such as residential buildings. The main thing for any algae habitat is humidity and light. Algae appear on the walls of houses, they are found even in hot springs with temperatures up to +85 ° C.

Some unicellular algae - mainly zooxanthelles - settle inside animal cells, remaining in stable relationships (symbiosis). Even the corals that make up Coral reefs, cannot exist without symbiosis with algae, which, thanks to their ability to photosynthesize, supply them nutrients necessary for growth.

Laminaria is a brown algae

What types of algae are there, and in what industries have they found their application? Currently, science knows about 30,000 varieties of algae. Brown algae have found their use in cosmetology - kelp (seaweed), ampheltia and fucus; red algae lithothamnia; blue-green algae - spirulina, chrocus, nastuk; blue algae - spiral algae and green algae ulva (sea lettuce).

Laminaria is a brown algae that was one of the first to be used in cosmetic products. Despite the fact that there are several types of kelp that look very different from each other, they all live only in cold, well-mixed water. The most famous is the sugar kelp (Laminaria Saccharina), which lives off the European coast and owes its name to the sweet taste of the mucus covering it. It grows in bushes, the size of which is directly dependent on the degree of protection of the habitat. It reaches 2-4 meters in length, its stem is cylindrical, turning into a long corrugated plate.

Wide famous name“sea kale” is historically associated with the palmate kelp (Laminaria digitata), living in places protected from the surf at the very upper boundary of the sublittoral - the sea shelf zone. Otherwise, kelp is called “witch’s tail.” The thallus of this algae, reaching a length of 3 meters, is an excellent visual example of the general structure of a macroalgae. The rhizoids (attachments), palmate, branched, with which the algae attaches to the stones are very clearly visible; stem - long, cylindrical, flexible and smooth; the plate is flat, solid in the lower section, and then cut into straps. This type of algae is especially rich in iodine, since kelp is always under water.

The use of algae of this type has been established in industrial scale. In addition to its nutritional purpose, it has valuable pharmacological properties. This type of kelp is especially known for its stimulating and tonic effect: it improves overall metabolism, is a source of microelements and is widely included in weight loss and anti-cellulite programs.

Numerous studies have shown that seaweed (and other algae) is distinguished by the fact that none of its components is harmful to patients, including those with malignant processes.

Fucus (fucus) is the second most important algae for cosmetics from the brown class (Phaeophycophyta). It grows on rocks in the coastal area and is collected by hand. Beneficial features These algae are due to the fact that they are extremely rich in iodine, vitamins, amino acids, plant hormones and microelements. You can find it on the beaches of the English Channel and along the entire Atlantic coast. For cosmetic purposes, two varieties of fucus are usually used:

Fucus vesiculosus

and Fucus serrafus.

The presence of a large amount of alginic acid determines the natural gelling and thickening ability of extracts of both kelp and fucus. Both algae are rich in organic and inorganic substances, which determine their high biological activity. Extracts of kelp and, to a greater extent, bladderwrack (Fucus vesiculosus) contain a complex of substances that stimulate the functioning of β-receptors and block α-receptors of fat cells, providing an effective anti-cellulite effect.

What is it - red, blue and green algae (with photo)

Red algae is a division of algae that lives in seawater.

Lithothamnia (Lithothamnium), like all red algae, they are found on underwater rocks North Sea, English Channel and Atlantic. It was colorfully described in 1963 by the famous submariner Jacques Cousteau. At a depth of a hundred meters, he discovered a red beach - a platform of limestone - lithothamnia. This algae looks like large pieces of pink marble with an uneven surface. Living in the sea, it absorbs and accumulates lime. Its calcium content is up to 33% and magnesium up to 3%, and in addition it has an iron concentration 18,500 times greater than sea ​​water. Lithothamnia is mined mainly in Britain and Japan. It is included in cosmetic products due to its ability to restore the balance of minerals in the body, but it is also popular as a food additive.

In face and especially body care products developed in last years, it is common to use a mixture of fucus algae, kelp and lithothamnia. Rich in inorganic compounds, lithothamnia perfectly complements the action of brown algae, providing a comprehensive effect on the skin and hair.

Blue algae is a spiral-shaped algae that grows in some lakes in California and Mexico. Thanks to their high protein content, vitamin B12 and P-carotene, they increase skin elasticity and have a remarkable firming effect.

Look how blue algae look in the photo - they differ from other algae in their rich blue-turquoise color.

Green algae are a group of lower plants. Ulva (Ulva lactuca)- sea lettuce is a green algae that grows on rocks. It can only be collected at low tide. Sea lettuce is a real storehouse of B vitamins and iron; they help strengthen body tissues and improve blood circulation in capillary vessels.

Spirulina is a blue-green seaweed and is used for healing. Spirulina from more than 30,000 species of algae contains the richest set of vitamins, microelements, amino acids, and enzymes. It is rich in chlorophyll, gamma-linoleic acid, polyunsaturated fatty acids and other potentially valuable nutrients - such as sulfolipids, glycolipids, phycocyanin, superoxide dismutase, RNase, DNase.

Spirulina differs from other algae in that it contains up to 70% of the most perfect protein; no other representatives of the plant and animal world on Earth contain such an amount.

Spirulina is the richest source of natural P-carotene, a vital antioxidant, and other carotenoids. Carotenoids are used by several organs in our body, including the adrenal glands, reproductive system, pancreas and spleen, skin and retina.

Only spirulina and mother's milk are complete sources of gamma-linoleic acid (GLA), which plays an indispensable role in ensuring the normal functioning of the body, all other sources are extracted oils. GLA helps prevent heart attacks and heart attacks, helps remove excess fluid, improves function nervous system and regulates cell reproduction, has anti-inflammatory properties, maintains healthy joints, and helps treat arthritis. GLA is also recognized as an important nutritional element for the prevention of skin diseases such as psoriasis. Spirulina contains the most perfect protein and all the essential amino acids. Spirulina protein does not require heat treatment for consumption, whereas other products containing protein must be boiled or baked (cereals, meat, fish, eggs), as a result of which certain forms of protein partially, and some completely, lose their beneficial qualities.

Spirulina does not contain hard cellulose in its cell walls, unlike other algae, but consists of mucosol saccharides. This allows its protein to be easily digested and assimilated in the body. Protein absorption is 85-95%.

Algae - countless numbers and variety various groups plants. Most of of them lives in water bodies. Other species prefer to be on the soil surface, tree bark, fences, and roofs. They only need moisture, for example, dew, groundwater, splashes of water from various sources. The body of algae contains one or more cells and is a kind of plate called a thallus. Some algae have a plate length of approximately 60 meters. Algae lack roots, stems, leaves and flowers. The components of an algae cell are a nucleus, cytoplasm, and one or more chloroplasts, which are called chromatophores.

Representatives of algae

In summer, sometimes some fresh water bodies turn green, that is, “bloom”. And the source of this phenomenon is chlamydomonas. Chlamydomonas is a single-celled microscopic algae. Thanks to their two flagella, these algae move. There is another type of algae called chlorella. This algae, in addition to water, likes to be in the soil and air. She has no flagella, so she cannot move. At the bottom of a reservoir or near the banks of a stream, mud is often found, which is created by the spirogyra algae. The body structure of spirogyra is cells elongated in a row, which are called filaments. Accordingly, this group of algae was called filamentous. Most people are familiar with the brown algae kelp - seaweed. It is edible and is often used in the diet of people and animals. There is another type of algae - porphyry. The length of the thallus of such algae can reach 2 meters and is red in color. Such algae are used in Food Industry(marshmallow production), paper and textile industries.
Algae is an important component in nature and human life. In nature, algae serve as:

• food for animals;
• place, from predators, some fish hide in thickets of algae.

In human life, algae are necessary for:

• food;
• fertilizers;
• livestock feed;
• production of paper, medicines;
• wastewater treatment.

Contains chloroplasts. Algae have different shape and sizes. They live mainly in water to depths where light penetrates.

Among the algae there are both microscopically small and giant ones, reaching a length of over 100 m (for example, the length of the brown alga Macrocystis pear-shaped is 60-200 m).

Algae cells contain special organoids - chloroplasts, which carry out photosynthesis. U different types they have different shape and sizes. Mineral salts and minerals necessary for photosynthesis carbon dioxide algae are absorbed from the water by the entire surface of the body and released into environment oxygen.

Multicellular algae are widespread in freshwater and marine reservoirs. The body of multicellular algae is called a thallus. A distinctive feature of the thallus is the similarity of cell structure and the absence of organs. All cells of the thallus are structured almost identically, and all parts of the body perform the same functions.

Algae reproduce asexually and sexually.

Asexual reproduction

Single-celled algae usually reproduce by division. Asexual reproduction algae is also carried out through special cells- spores covered with a shell. Spores of many species have flagella and are able to move independently.

Sexual reproduction

Algae are also characterized by sexual reproduction. The process of sexual reproduction involves two individuals, each of which passes on its chromosomes to its descendant. In some species, this transfer is carried out by the fusion of the contents of ordinary cells; in others, special sex cells - gametes - stick together.

Algae live primarily in water, populating numerous marine and freshwater bodies of water, both large and small, temporary, both deep and shallow.

Algae inhabit water bodies only at those depths to which it penetrates sunlight. Few species of algae live on stones, tree bark, and soil. Algae have a number of adaptations for living in water.

Adaptation to the environment

For organisms living in oceans, seas, rivers and other bodies of water, water is their habitat. The conditions of this environment are noticeably different from ground conditions. Reservoirs are characterized by a gradual weakening of illumination as one goes deeper, fluctuations in temperature and salinity, and low oxygen content in water - 30-35 times less than in air. In addition, water movement poses a great danger to seaweed, especially in the coastal (tidal) zone. Here algae are exposed to such powerful factors as surf and wave impacts, ebb and flow (Fig. 39).

Survival of algae in such harsh conditions aquatic environment possible thanks to special devices.

• With a lack of moisture, the membranes of algae cells thicken significantly and become saturated with inorganic and organic substances. This protects the algae body from drying out during low tide.
• The body of seaweed is firmly attached to the ground, so during surf and wave impacts they are relatively rarely torn off the ground.
• Deep-sea algae have larger chloroplasts with a high content of chlorophyll and other photosynthetic pigments.
• Some algae have special bubbles filled with air. They, like swimming trunks, hold the algae at the surface of the water, where it is possible to capture the maximum amount of light for photosynthesis.
• The release of spores and gametes in seaweed coincides with the tide. The development of the zygote occurs immediately after its formation, which prevents the tide from carrying it into the ocean.

Representatives of algae

Brown algae

Kelp

The seas are inhabited by algae that are yellow-brown in color. These are brown algae. Their color is due to the high content of special pigments in the cells.

The body of brown algae has the appearance of threads or plates. A typical representative of brown algae is kelp (Fig. 38). It has a lamellar body up to 10-15 m long, which is attached to the substrate with the help of rhizoids. Laminaria reproduces by asexual and sexual methods.

Fucus

In shallow water dense thickets forms fucus. Its body is more dissected than that of kelp. In the upper part of the thallus there are special bubbles with air, due to which the body of the fucus is held on the surface of the water.

On this page there is material on the following topics:

• structure of fucus indicate body parts

• structure nutrition algae reproduction

• differences and commonalities between unicellular algae and multicellular

• fucus what they eat how they reproduce

• what algae can live at the greatest depths

Questions for this article:

• What organisms are algae?

• It is known that algae inhabit seas, rivers and lakes only at those depths to which sunlight penetrates. How can this be explained?

• What is common and distinctive in the structure of unicellular and multicellular algae?

• What is the main difference between brown algae and other algae?

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