Variety of algae
Algae are a very ancient group of organisms on Earth. During their existence, algae have developed many forms of structure, features of reproduction and settlement on our planet. In total there are about 30 thousand species of algae.
Based on the structural features and color of the thallus, green, red, golden, brown, diatoms and other algae are distinguished.
Green algae. Among them there are unicellular and multicellular. These include chlorella, ulva, spirogyra, chlamydomonas, ulotrix .
Sort of chlamydomonas- more than 500 species. Almost all of them are inhabitants of small, well-warmed and heavily polluted water bodies. Along with the autotrophic method of nutrition, all representatives of Chlamydomonas absorb organic substances dissolved in water over their entire surface, helping to purify polluted waters. This ability of these algae allows them to be used in wastewater treatment plants.
In ponds, lakes, and river backwaters you can often see slippery green mud floating on the surface of the water. If you examine the mud under a microscope, you can see that it is formed by a large accumulation of tiny green threads. It is a multicellular filamentous algae spirogyra. Bright green algae grows in slightly polluted waters of sea coasts, such as the Black Sea. ulva, the flat wavy thallus of which reaches a width of 20 cm. Many peoples use ulva as food under the name “sea salad”.
Some colonial forms also belong to the department of green algae -Volvox, Eudorina, Pandorina . Their individual cells are built like chlamydomonas, but when they multiply, the cells do not disperse, but grow together with their membranes or remain connected by a common mucus. They are widespread in stagnant bodies of water, where they also cause algal blooms. Volvox is the most highly organized. In his colony, some specialization of cells is already observed.
If fresh water bodies are the usual environment for green algae, then the vast majority of brown and red algae form real forests and thickets in salt water. They live both in the tidal zone, where they remain without water for a long time and survive the shock of waves, and at quite a considerable depth, where the sun’s rays almost do not penetrate.
Interactive lesson-simulator "Green algae department".
(Go through all pages of the lesson and complete all tasks)
Brown algae - These are large, multicellular plants. They got their name because of the color of the thallus. In addition to chlorophyll, the cells of these algae contain other pigments.
Most brown algae grow attached to solid ground or to other algae, which makes them different from other algae. To attach to the ground, they use special outgrowths of the thallus - rhizoids , which are long root-like growths. Brown algae are either annual or perennial. For example, at kelp The rhizoids and stem are perennial, and the long ribbon-like (lamellar) part of the thallus is annual. It grows back from the stem every year.
Brown algae can reproduce vegetatively. With the help of biflagellate spores - asexually. From the spores, individuals grow, on which sex cells are formed - gametes. After fertilization, the zygote gives rise to algae on which spores will form. Consequently, brown algae are characterized by an alternation of two generations - sexual and asexual.
Brown algae is one of the main sources organic matter in the coastal zone of oceans and seas.
Numerous animals take refuge in their thickets, similar to an underwater forest, and find food and oxygen. Many brown algae are used as food for humans, used in industry, used as livestock feed and as fertilizer.
Red algae, or scarlet. A set of different pigments in combination with chlorophyll determines the color of scarlet mushrooms - from bright red to bluish-green and yellow. This is a very ancient group of algae. Therefore, they have some differences from other, “younger” departments. Red algae are shorter in length than brown algae (no more than 2 m). The combination of different pigments of scarlet mushrooms gives them a color from bright red to bluish and yellow. Reproduction of red algae (asexual and sexual) is a more complex and diverse process than that of other departments. Purple ducks have surprisingly adapted to life in the coastal zone. Here they are washed not only with sea water, but also fresh water, freeze in winter, dry out at low tide. But the tide comes and they come to life. It is the scarlet ones that can survive on rocks where the surf is constantly active. The purple thallus grows for many years and has the most different shapes: lamellar, bushy, filamentous. The most famous seaweedpurple. It reproduces only sexually.
(Complete all lesson tasks)
The meaning of algae great in nature. They absorb sunlight penetrating to a considerable depth and form organic substances. At the same time, oxygen is released into the water, and carbon dioxide is absorbed from the water.
Brown algae are one of the main sources of organic matter in the coastal zone. Their biomass can reach tens of kilograms per square meter. Thickets of brown algae serve as shelter, breeding and feeding sites for coastal animals. They also create conditions for the settlement of other, smaller algae. Charles Darwin wrote aboutmacrocystis piriformis , which occupies the same position in the southern seas as kelp in the northern: “These huge underwater forests I can only compare with the terrestrial forests of tropical regions. And yet, if a forest were destroyed in any country, I don’t think that even approximately the same number of animal species would die as with the destruction of this algae.”
Man widely uses algae. In medicine - previously only for the production of iodine, but now - in the manufacture of blood substitutes, drugs that help remove radioactive substances from the body, in surgery. Residents of Japan and Far East have long been used as food kelp. However higher value We purchased these algae from the industry today.
obtained from algae chemicals, necessary in the manufacture of tablets and diabetic products; in the production of plastics, synthetic fibers, resins, paints, paper, explosives. Adding small amounts of them improves the quality of long-lasting products (canned food, ice cream, juices). Brown algae is used in animal husbandry and crop production. Brown algae contains iodine and other trace elements, so feed flour is prepared from them - an additive to feed for farm animals. Thanks to this, livestock mortality is reduced, productivity increases, and the iodine content in milk and eggs increases. Porphyra can be used for food. In Japan it is specially bred.
Red algae is used to produce agar-agar. It is added to bread so that it does not go stale; marshmallows, jelly, and marmalade are made from it. Agar-agar is the best medium for growing microorganisms. Capsules and tablets with antibiotics and vitamins are made from agar. Iodine is obtained from red algae. Flour is produced from scarlet grass along with other algae, which is used as livestock feed and as fertilizer. Red algae grow in all seas of the World Ocean, but their role is especially significant in the tropics, where they outnumber brown and green algae. In the life of the sea, they play a role similar to brown and green.
In addition to multicellular, rather large algae, the World Ocean is home to a huge number of microscopic algae. Together with the spores of multicellular algae, they form phytoplankton (from Greek phyton- plant and plankton- wandering). It inhabits surface, well-lit layers of water. This is the main producer of organic substances, the initial link of most food chains in the reservoir.
In fresh water bodies, green algae take the place of red algae and brown spores in phytoplankton.
Algae are lower plants with a unicellular and multicellular structure. They are called lower because their body is not differentiated into absorbent and photosynthetic parts, as is observed in all other representatives of the plant kingdom. Algae is one of the oldest representatives of organisms, a gigantic source of oxygen, organic substances and energy for the entire living world. They contain many valuable substances used in industry, agriculture, medicine and human nutrition. Algae are great value of our planet.
As part of the implementation of new educational standards at the secondary level, in 5th grade biology lessons, a system-activity approach to learning is actively implemented, using problem-based learning technology, ICT technologies, etc. This master class can be used as a lesson in updating knowledge or a lesson to consolidate knowledge.
Objective of the lesson: study the structure of multicellular algae and their diversity, as well as their significance for humans and in nature.
Lesson objectives:
· introduce students to the structural features of multicellular algae, their significance in nature and human life;
· continue to develop the ability to work with a textbook;
· activate and integrate knowledge in related disciplines.
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Preview:
Topic: “Diversity of algae and their importance in nature and human life”
“A vast ocean of the unknown surrounds us. And the more we know, the more mysteries nature asks us,” these words belong to scientist V.A. Obruchev.
Objective of the lesson: study the structure of multicellular algae and their diversity, as well as their significance for humans and in nature.
Tasks:
- introduce students to the structural features of multicellular algae, their significance in nature and human life;
- continue to develop the ability to work with a textbook;
- activate and integrate knowledge in related disciplines.
Planned learning outcomes
Subject: Students have an idea of multicellular algae as representatives of lower plants and their characteristic features.
Metasubject: The ability to work with textbook text and illustrations develops.
Personal: elements are formed communicative competence in communication and cooperation with classmates in the process of educational activities.
Basic concepts of the lesson:lower plants, higher plants, algae: green, brown, red, thallus (thallus), rhizoids, chromatophore,
Student activities:working with textbook text and illustrations, collaborating with classmates during discussions, working with flashcards.
Equipment: ICT personal computer, interactive whiteboard, multimedia film projector, presentation, tables with images of algae, herbarium, seaweed, flashcards, a jar of seaweed salad, ice cream, a piece of leather, a jar of paint, agar-agar, iodine.
Lesson progress:
Teacher: - Hello, dear guys! I'm glad you came to class today in a good mood.They say a smile is the kiss of the soul. Let's look at each other and smile. Take your seats. I have no doubt that today you will work together and actively in class.
Please note that on your desks there are individual assessment sheets in which you will complete tasks today and grade yourself, sign them.
- Knowledge test:work in individual student cards.
Teacher:
Mystery: There are hundred-meter snakes,
Green, purple,
There are brown and burgundy ones.
And to the captain at sea
They cause great grief.
(Seaweed)
Why are algae classified as lower plants, please explain?
What science studies algae?
Why are algae called “the oldest”?
Task No. 1. Guys, select from the proposed list the characteristics characteristic of plants. For every correct answer 1 point.
- Found everywhere.
- Move actively
- motionless
- They absorb carbon dioxide and release oxygen, purifying the air.
- They feed by photosynthesis.
- They feed on ready-made organic matter.
- There are lower and higher.
- The body may consist of a single cell or be multicellular.
- The cell is covered with a cellulose membrane.
- The cytoplasm contains a vacuole with cell sap.
(Correct: 1, 3, 4, 5, 7, 8, 9, 10) Max-8 points
Task No. 2. Max – 5 points
- The science of algae is called ………(Algology)
- …………. They live not only in water, but also on land. (Seaweed)
- Multicellular algae attach to the substrate using - .....(rhizoids)
- The body of the algae is called……..(thallus).
- The method of nutrition of algae is ……….(photosynthesis).
(Correct answers: algology, algae, rhizoids, photosynthesis, thallus)
Task No. 3 . Look at the picture and find the algae on it. Why do you consider this plant to be an algae? (2 points for a complete correct answer, 1 point for a partial answer)
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- Learning new material:
1. Updating knowledge.
Problem: On the teacher's desk: a jar of seaweed salad, ice cream, a piece of leather, a jar of paint, herbarium specimens of algae.
Question: What can unite all these items? (students express their guesses, but the teacher suggests returning to the answer to the question at the end of the lesson?
So, the topic of our lesson: “The diversity of algae and their importance in nature and in human life.”
2. Classification of algae:
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Rice. 2 Chlamydomonas | Rice. 3 Ulotrix |
(1 point)
TEACHER: - Among algae there are unicellular, colonial and multicellular forms. The body of multicellular algae has no standing roots, stems or leaves and is calledthallus (thallus), are attached to the substrate using rhizoids . Unicellular algae are microscopic organisms, and the size of multicellular algae can reach tens of meters (macrocystis 150-300 m). (we write down the diagram (a) on the board, and the students in their notebooks).
Now we are working in groups (the class is pre-divided into three groups, curators are assigned). First group - pp. 95-97, while reading and working with drawings, we supplement the table with examples of representatives of green algae. Second group - p.98 while reading, supplements with examples of representatives of brown algae. Third group – pp. 98-99, while reading and working with pictures, supplements the diagram with examples of green, brown and red algae. 3-4 minutes to work.
Plant Kingdom
Inferior Superior
Seaweed
Unicellular Multicellular
Greens
(chlamydomonas) Green Brown Red
Chlorella (Ulva) (Lainaria) (Porphyra)
(5 points)
The group's work is checked for interactive whiteboard while drawing up the diagram.
DYNAMIC PAUSE (1.5 minutes)
3. Diversity of multicellular green algae.
Students listen to the speakers and fill out the section “What do I know about the importance of algae?” in the table.
Teacher: Green algae are unicellular and multicellular, forming filaments, spherical colonies, leaf-like structures, etc. One well-known genus is Pleurococcus, a single-celled algae that produces green growths often seen on the bark of trees. The largest green algae is sea lettuce (Ulva), a leaf-shaped macrophyte. In the process of life, cells divide and the algae grows. In a favorable period, it reproduces asexually, and in an unfavorable period, it reproduces sexually, i.e. with the help of gametes.
STUDENT 1: Chlorella is a veteran of space biology: during space flights, experiments were conducted to purify the air and process organic residues in the compartments of spaceships. Among the mobile green algae, Volvox is known, which was discovered by Anthony Van Leeuwenhoek and compared it with the Universe.
Teacher: Thus, off the coast of the Gulf of Mexico, the berry-bearing sargassum dominates. During a storm, raging waves carry it away and transfer it to the Gulf Stream, which carries it far into the ocean. The long drift ends near the Azores, where plants accumulate in a calm sea. Sailors were afraid to enter the waters of this sea. What kind of sea are we talking about and what algae form it?
4. Brown and red seaweed (student report). STUDENT 2: Brown algae- in this group there are no single-celled organisms; they all form thalli - from thin threads from one row of cells to huge (up to 50 m!) stripes and ribbons of brown and bluish-brown color. Brown algae are immobile, attached forms. Reproduction is vegetative, asexual and sexual. Brown algae live primarily in the sea, with the exception of a few freshwater species. Almost all brown algae grow attached to the seabed, rocks, and other algae. Only the sargassum of one of the areas of the Atlantic, surrounded by a ring current, floats freely on the surface, supported by small berry-shaped floats - bubbles.
STUDENT 3: Laminaria algae, known in everyday life as seaweed, is of great benefit to people. Its thallus reaches a length of several meters. In many countries in Europe, Asia and America, kelp is used as food, livestock feed, and for industrial processing. Valuable drugs are obtained from them - alginate, mannitol, laminarin. Laminaria has been used especially for a long time and widely in Japan and China. It is used to make vegetable caviar and purees, salads, canned food and even... candy. Alginic acid salts– alginates can bind 300 volumes of water per unit volume, forming a viscous solution. Alginates are required in the production of ice cream, fruit juices, canned food, plastics, varnishes and paints; they are needed in the textile industry, printing, medicine, perfumery and even in foundry. No less important is another product obtained from brown algae - hexahydric alcohol mannitol. It is needed both in the treatment of diabetes and in the manufacture of leather, paper, varnishes, and paints. They also make strong explosives from it. In the seas of the southern hemisphere, the world's largest algae is found - the famous pear-bearing macrocystis. Its total length (according to scientists) reaches from 150 to 300 m and more.
STUDENT 4: Red algae are multicellular, very rarely unicellular, of complex structure, most of them are marine leaf-shaped, bushy or crustaceous macrophytes that live below the low tide line. Red algae are benthic plants and are not found in plankton. They penetrate to great depths (up to 200 m). The reason for the shade tolerance of red algae is their photosynthetic pigments. The color of algae depends on the depth of their habitat. In shallow water they are yellow-green or bluish in color, deeper they turn pink, then turn red. The most intense red color is at a depth of more than 50 m. But this is how they look when pulled to the surface in direct sunlight. Divers at the bottom see them as black: after all, the red rays are absorbed by the first meters of water. Photosynthesis of red algae occurs in blue rays, which penetrate most deeply into the water. The methods of reproduction of red algae are varied: division of the thallus, spores (without flagella). The sexual process is very complex.
STUDENT 5: One of the algae living in the North Sea, chondrius, has long been used in dry form as a medicine for respiratory diseases. Agar-agar is obtained from other scarlet plants, which is used in all microbiological laboratories in the world to obtain pure cultures of microbes. However, they cannot do without it food industry, and even in the production of motion picture films. Confectioners and bakers add a small amount of agar-agar to the dough so that cakes, biscuits, and bread do not go stale longer. In some red algae, the thalli are heavily saturated with lime, causing them to look like corals. Many coral reefs are largely formed by these dead algae. Unlike corals, they go far to the north, forming red-pink crusts on the rocky bottom in the Barents and White Seas in places with strong currents.
Teacher: Guys, rate your work on a five-point scale. When evaluating, take into account: how interesting was it for you? educational material; how often were you distracted? was everything clear to you; did you take an active part in at this stage lesson.
5. The importance of algae in nature and human life (6 min.)
Students work independently with the text of the textbook, pp. 99-101, and take notes in their notebooks.
Meaning of seaweed:
«+» | What do I know about the meaning of algae? | « - » |
The benefits of algae. Food for aquatic animals. Food for humans. Source of agar-agar Medicines. Paper. Cali Soil formation process. Source of iodine. Mineral salts. Glue, varnishes, paints. | Harm caused. They pollute water sources, often giving it an unpleasant taste and odor. Beach litter. During storms, many marine macrophytes are torn from the substrate and thrown onto the beach by waves and wind, literally covering it with their rotting mass. Death of fish. Causes poisoning and illness. Several types of algae, when ingested by animals, cause poisoning, sometimes fatal. Others turn out to be a disaster in greenhouses or damage plant leaves. |
After the specified time, the teacher provides the correct answers on the board(Table in notebook).Correct mistakes and give themselves points for this task - max – 5 points.
- Consolidation-reflection.
- "Black box". Each group is given Black Boxes containing mysterious algae-related objects. Students read the task and guess what is in the box. For a correctly guessed riddle, a 1 point.
1 box (first group)–
Here's the medicine. Don't be afraid:
For health and beauty
Children smear it on their knees,
Elbows, cheeks and noses. (IODINE)
2 drawer (second group)–
Look! Underwater
A whole garden has grown.
He will feed you and me,
It will end up in the salad. (seaweed salad, jar of lettuce)
3 drawer (third group) -
Separately, I’m not so tasty,
But everyone needs food. (SALT)
- “You - for me, I - for you.”Work in pairs. Students are asked to make up two questions and ask each other. The first question is about the structure of algae. The second question is about the importance of algae. Max. 2 points.
Teacher: - Guys, today in the lesson we got acquainted with the diversity of algae, their significance in nature and human life, and I think that now you are ready to answer the question asked at the beginning of the lesson, what can unite all the objects on my table?(Answer: they are all made either from algae or using algae products)
Reflection:
What did you like about today's lesson?
What new did you learn?
What didn't you understand?
Summing up:points are calculated
Max-30 points.
30-26 – score 5
25-21- score 4
20-16 score 3
Below 16, guys, don’t despair, study the material at home and consolidate it? after the paragraph.
IV. Homework. P.18 read, vocabulary work. Creative work: message or abstract.
Literature:
- http://biolicey2vrn.ru/index/mnogoobrazie_vodoroslej/0-92
- Biology. Bacteria. Mushrooms. Plants. 5th grade: textbook. For general education Institutions / V.V. Beekeeper. – M.: Bustard, 2012. – 141, (3) p.
- Biology: Diagnostic works for the textbook by V. Pasechnik “Biology. Bacteria, fungi, plants. 5th grade”/ V.V. Beekeeper. – M.: Bustard, 2015. – 92 p.
- Secrets of nature: A manual for students in grades 5-7/Compiled by T.S. Sukhova, V.I. Stroganov - M.: Venta-Graf, 2001. - 208 p.: ill. (Behind the pages of the textbook).
Preview:
Scorecard
Student of class 5B____________________
Task No. 1 .Guys, select from the proposed list the characteristics characteristic of plants. For every correct answer1 point. Max. 8 points.
Write down the numbers of signs_______________________________ points
Task No. 2. Fill in the missing word according to its meaning. For each correct answer - 1 point, Max – 5 points
- The science of algae is called - ………
- …………. …..they live not only in water, but also on land.
- Multicellular algae attach to the substrate using -………..
- The body of algae is called -………………
- The method of feeding algae is ……………...
Points
Task No. 3 . Look at the picture and find the algae on it. Why do you consider this plant to be an algae? (2 points for a complete correct answer, 1 point for a partial answer)
Points
Task No. 4. Algae classification:
Rice. 1 Volvox Fig. 2 Chlamydomonas | Rice. 3Ulotrix |
Examine the picture and identify differences in the structure of the plants depicted on it. What two groups of “Algae” can be distinguished based on this picture?(1 point)
Points
Task No. 5. Draw up a classification scheme for Algae, supplement it with examples.
Biology lesson plan.
Subject: Algae, their diversity and importance in nature.
Class 6 (FSES).
UMK N.I. Ponomarev.
Textbook: Biology: 6th grade: textbook for students of general education institutions / I.N. Ponomareva, O.A. Kornilova, V.S. Kuchmenko; edited by prof. I.N. Ponomareva. - M.: Ventana-Graf
Objective of the lesson: form an idea of algae as lower plants.
Tasks:
1.Introduce the features of the habitat, structure and life activity of algae;
2.Study the general characteristics of algae;
3. Identify the characteristics of unicellular and multicellular algae;
4.Continue to develop skills to work with various sources information: textbook, electronic educational program 1C: School, etc. ICT (audio content, video content, multimedia).
5. Fostering environmental literacy and careful attitude to the algae habitat.
Equipment: interactive equipment "Promethean", presentation files, PC, magnetic board with magnets, herbarium material "algae", blank sheets A-4(to create a diagram, reference signs in the work of groups),
Usage of UUD components:
Ability to hear, listen, plan and carry out joint work in a coordinated manner;
Interact with each other, provide support to each other, be able to lead a discussion;
Express your thoughts correctly;
Collaborate effectively with both the teacher and peers;
Willingness to carry out targeted search, processing and use of information in work;
Ability to identify what is essential;
Ability to understand a cognitive task;
Understand information presented in pictorial, schematic form,
Use iconic and symbolic means;
Ability to solve problems and problems.
Skills in developing arbitrary behavior in individual and joint work;
Emotional assessment of what is happening and what has been learned;
Progress of the lesson.
- Testing students' knowledge.
What is the importance of systematics in the study of living nature?
What are plant species called?
What taxa are identified in the classification of plants.
Natural scientist who introduced binary species names.
Establish correspondences between taxonomic units and proposed group names. Which group name is redundant and why?
Which plants are considered higher?
Intermediate result:determining the quality of assimilation of the studied material “Plant taxonomy, its significance for botany.”
- Studying the material.
Educational component 1. | Teacher's actions | Student actions |
Video of algae (EOP 1C: School). | Shows a video. Offers to answer questions about the video. Determines what students learned after watching. Asks questions about the plot. Habitat of organisms. What forms of organisms did you see? What sizes can organisms have? Statement of the problem, lesson goals. Helps define the problem and purpose of the lesson. Explains that this is a special group of plants “Algae”. | Watch the video carefully. They think and analyze information. Answer questions. Assume the purpose of the lesson. Write down the topic of the lesson in a class notebook. |
Intermediate result:determining the purpose of the lesson. Understanding that there are similarities and differences between the plants presented. Understanding the need to study the structural features of algae.
Educational component 2. | Teacher's actions | Student actions |
Working with the text of the textbook, illustration No. 107,108 | Explain the task to the students. Helps students work with text and illustrations. Listens and focuses students' attention on what is important. Checks the quality of work. Asks questions. How do algae differ in their structure? In what structures is chlorophyll located? What body shapes do algae have? What is the name of a single-celled algae? What structural features of Chlamydomonas are characteristic of a plant cell? What structures are characteristic of a free-living organism? What process is the presence of these structures associated with? Listens to students' answers, complements and notes correctly identified signs. Offers to compare student answers with the answers on the slide. | Active listening. Understanding the task. Work with textbook text and illustrations. They think and interact with the teacher. Answer questions. They listen carefully to their classmates’ answers, give comments on the answers, and correct mistakes. They make a generalization. Write down the signs of the “Algae” department in a notebook. |
Intermediate result:assimilation general characteristics department "Algae". A) Algae are lower plants, because the body is represented by a thallus, or thallus. It has no organs or tissues. B) Chlorophyll is found in chromatophores. C) Algae are autotrophic organisms. Understanding the differences between algae. A) There are unicellular and multicellular algae. B) The body shapes of algae are varied. C) Chlamydomonas has flagella, an ocellus, and a contractile vacuole - structures characteristic of a free-living organism.
Educational component 3. | Teacher's actions | Student actions |
Consolidation of the material “Structure of a unicellular algae”. EOP 1C: School and task No. 2 " workbook». | Explains the purpose of the work, motivates to complete the work, provides assistance in completing the work in the “workbook”. Checks the quality of work using a test version of the manual in EOP 1C: School | Complete task No. 2 in the “workbook” to consolidate knowledge of the structure of a unicellular algae. Collaborative interaction with the teacher. Work with an interactive manual. They show the quality of the task, the degree of mastery, and select the correct answer from the proposed options. The structural structures of Chlamydomonas and its function are named. Interact with the teacher in work. |
Intermediate result:knowledge of the structural features of unicellular algae. Assimilation of body parts, functions of body structures. Memorizing new concepts and consolidating knowledge of the structure of a plant cell and the structures of free-living organisms.
Educational component 4. | Teacher's actions | Student actions |
Studying the block “Reproduction of algae”, “Diversity of algae”, “Importance of algae” | Divides class students into working groups. Explains the task for each group. Provides assistance in preparing for a performance and in creating a diagram. Maintains a high pace of work, focusing on the content of the material in each group. Encourages thinking in groups, creates a favorable situation in the group's work, a situation of success. At the end of the groups' performances, he checks the accuracy of the students' notes. Shows herbarium specimens of “algae”, a bottle of iodine, a food product. | The work is done in groups. Group 1 is working on the content of the material “Reproduction of algae”. Group 2 – “Diversity of algae”, Group 3 – “Importance of algae”. In groups, they analyze the content of the material, discuss, and determine the content of their story. Interact with the teacher. Develop a diagram of the material for subsequent recording in notebooks by class students. Performing in front of classmates. They offer a diagram of their part of the material. After the performance of each group, transfer the diagrams of the main part of the material to a notebook. |
Intermediate result:skills of working in a group and interaction with group members and the teacher have been developed. A joint analysis of the content of the material was carried out. Skills and abilities in using diagrams, tables, reference signs, etc. have been developed. when solving a learning problem. Knowledge of the characteristics of algae reproduction, the diversity of algae, and the importance of algae has been acquired.
Scheme No. 1. “Reproduction of algae”
Scheme No. 2. “Diversity of algae”
Names of algae.
Depth of habitat in water bodies.
Scheme No. 3. “The importance of algae”
Participate in the formation of oxygen, saturation aquatic environment and the atmosphere with oxygen;
Conducts a short survey on the studied blocks. Summarizes the work of the groups. Summarizes the material studied. After watching the video, it invites you to think about the role of algae in the existence of living beings on the planet. Poses a problem to think about.
The role of humans in the conservation of biological diversity.
The role of humans in preserving algal habitats.
Ways to solve the problem of water pollution.
Effective and safe methods for cleaning water bodies for aquatic life.
Carefully watch the video and evaluate the information in the video. They talk about what they additionally learned from the film.
They think about the problem. They answer questions and offer solutions to the problem.
Intermediate result:thinking about seagrass conservation and protecting seagrass habitat. Emotional assessment and attitude towards environmental problems. The ability to offer your own conclusions, your own ways to solve a problem. Consolidation of the studied material.
- Summing up.
Use the interactive capabilities of ICT;
Prepare equipment and interactive aids for the lesson;
Maintain the time frame of each teaching component of the lesson;
Provide measured assistance to students in their work, motivate them to study the material, create a situation of success for each student;
Involve low-performing students in the survey and work, offering them a form of work that can be successfully completed (for example, working with an interactive manual with ready-made answers);
Use various forms of perception of the material;
Use multivariate forms of work,
It is mandatory to include a textbook in your work, without overloading the lesson with presentations and slides.
In preparation for the lesson, materials from the Internet resource were used
Algae are generally referred to as plants that grow in water, but the group of living organisms is much larger and includes single-celled life forms, some of which are less than microns in size. They can live:
- in the water column, without being attached to any object or inhabitant underwater world;
- at the seabed, attaching to it and other algae with a thallus;
- in the upper layers of the soil;
- on trees, fences, house walls, etc.
Types of algae
Algae are distinguished by the number of cells:
- unicellular;
- multicellular (mainly filamentous);
- colonial;
- non-cellular.
There is also a difference in the cell structure and pigment composition of algae. In this regard, the following are highlighted:
- green(with a green tone and slight splashes of yellow);
- blue-green(with pigments of green, blue, red and yellow);
- brown(with green and brown pigments);
- red(with pigments of various shades of red);
- yellow-green(with coloring in corresponding tones, as well as two flagella of different structures and lengths);
- golden(with pigments that form a golden color, and cells that do not have a shell or are enclosed in a dense shell);
- diatoms(with a strong shell, consisting of two halves, and a brownish color);
- pyrrophyta(brownish-yellow in color with bare or shell-covered cells);
- and also euglena algae(unicellular, naked, with one or two flagella).
Algae reproduce in several ways:
- vegetative(by simple division of body cells);
- sexual(fusion of germ cells of a plant to form a zygote);
- asexual(zoospores).
Depending on the type of algae and how favorable the environmental conditions are, the number of generations in just a few years can exceed 1000.
The influence of algae on the environment
All types of algae produce oxygen due to the presence of chlorophyll in their cells. Its share of the total volume produced by plants on planet Earth is 30 - 50%. By producing oxygen, algae absorb carbon dioxide, the percentage of which is quite high in the atmosphere today.
Algae also act as a source of food for many other living creatures. They feed on mollusks, crustaceans, various types fish Their high adaptability to harsh conditions provides high-quality nutrition for plants and animals high in the mountains, in polar regions, etc.
If there are too many algae in reservoirs, the water begins to bloom. A number of them, for example, blue-green algae, actively release a toxic substance during this period. Its concentration is especially high at the surface of the water. Gradually, this leads to the death of aquatic inhabitants and a significant deterioration in water quality, up to waterlogging.
The value of algae for humans
Algae benefit not only flora and fauna. Humanity also actively uses them. The vital activity of organisms in the past has become a source of minerals for the modern generation, the list of which includes oil shale and limestone.
Algae that are edible for humans are consumed as food. They enrich the body with useful microelements and are a source of iodine.
A number of algae are actively used to purify water in artificial closed systems, such as aquariums.
They extract useful substances from algae, which are used as dietary supplements, are included in vitamin and mineral complexes and are actively used in cooking.
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EPIGRAPH
Any tribe on earth owned in childhood a poetic mirror, where the world was reflected in a whimsical way, each in its own way; This is how the first impressions of life were formed into an epic, an invaluable aid to knowledge national biography along with the remains of material culture. L. Andreev
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STATION "HISTORY"
East Slavic era - the period of the emergence of epics
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STATION "LITERATURE"
Heroic epics songs telling about great deeds extraordinary people
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Ilya Muromets - the most favorite epic image
Like one red sun in the sky, And one in Rus' Ilya Muromets!
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Tell us about the fight between Ilya Muromets and Nightingale the Robber. How did the opponents behave in battle? What helped the hero defeat the Nightingale the Robber? What character traits of the hero appeared during the battle?
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Ilya Muromets
Thanks to modern scientific methods, a reconstruction of Ilya’s appearance was carried out. Its results confirmed many information about the hero of epics: he had a heroic physique, tall and until the age of 33 he could not move due to spinal paralysis.
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STATION "PAINTING"
“I have always lived only in Russia.” V.M. Vasnetsov
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MUSIC STATION
Melodiousness, melody, rhythm
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Why is this station the last?
Yes, because the melodies of history, literature, painting merge for you and me in wonderful music Ancient Rus'. It reminds us of the life of our great ancestors. You must remember that from them we inherited great story, rich literature, the finest national music.
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Homework:
1.Work on textbook questions. 2. Independent reading of epics. 3.Write an essay – an argument “Why are you interested in epic heroes to you?"
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