Download presentation on lichens. Biology presentation "Lichens. The diversity and importance of lichens." where vegetation is sparse
cells
seaweed
hyphae
mushroom
Synthesis of organic substances
Minerals and water.
Lichens are symbiotic organisms consisting of algae and fungal hyphae.
Algae cells
Mushroom threads
Lichens are photophilous, water-loving, undemanding to the substrate, sensitive to air pollution - biological indicators of air purity.
Lichens grow very slowly - growth per year for cortical - 1-8 mm, for bushy - 1-35 mm.
lecidea
archill
peltiger
xanthoria
cladonia
falling asleep
reindeer moss
- Destroy rocks
- They form the soil.
- The main food for deer in the North.
- Paints and litmus are obtained from them.
- Also used in medicine and perfumery.
- Bioindicators
Cetraria Icelandic
"Icelandic Moss"
- Yagel grows very slowly: a few millimeters per year.
- Therefore, the same tundra pasture cannot be used for several years in a row - it is no coincidence that the Sami roamed with their herds throughout the region.
- If deer eat the whole moss moss, then it takes quite a long time to restore the lichen cover - up to 15 years
Deer looking for reindeer moss in winter
“Does a water cliff protrude from the waves of the ocean, does a piece of rock break off, revealing a fresh, unweathered fracture, does a boulder break, which has lain underground for centuries, everywhere on a bare barren surface the lichen is the first to appear , decomposing the rock, turning it into fertile soil.
K.A. Timiryazev
"Plant Life"
Asahineya Scholander
Graceful cladonia
Leptogium Burnet
Lobaria pulmonaria
The Bible tells of a people who wandered through the desert for many days, knee-deep, drowning in the sand. All supplies taken with them were eaten. Many fell from exhaustion and exhaustion on the hot sand.
In the morning, when the sun began to heat up the sand, the wind suddenly rose. Everyone saw gray lumps rolling along the sand, driven by the wind. A strong gust of wind lifted them up, it seemed that they were falling from the sky.
"Manna, manna! Manna is falling from the sky!” Everyone who could still rushed to collect this "manna". They eagerly ate dry gray lumps, cooked porridge from them and baked cakes.
- What do you think this manna really was?
In 1772, the Russian scientist P.S. Pallas proved that it was an edible lichen that is carried by the wind over the vast expanses of Africa and Asia Minor.
- 1 option. Choose the correct statements: The answer is yes or no.
- Lichens are members of the plant kingdom.
- Lichens absorb water from the soil through their roots.
- Algae synthesize organic matter, fungi absorb water and minerals.
- Man uses lichens in his life.
- Lichens grow in polluted areas.
- Option 2. Choose the correct statements: The answer is yes or no.
- Lichens are a single organism consisting of a fungus and algae living in symbiosis.
- Lichens can be found in forests, mountains, and meadows.
- Lichens grow quickly.
- Paint is made from lichens.
- Lichens settle only on fertile soils.
Lichen - benefit or harm to a tree?
slide 1
Lichens
Lichens are usually considered separately from fungi, although they belong to them, being a specialized group. They are quite diverse in appearance and coloration and number 26,000 species united in more than 400 genera. Lichens are an example of an obligate symbiosis of fungi with algae. According to the nature of sexual intercourse, lichens are classified into two classes: marsupials (reproduce by spores that ripen in bags), which include almost all varieties of lichens, and basidial (spores mature in basidia), numbering only a few dozen species.
slide 2
Lichen structure
Most lichens consist of a dense bark formed by hyphae, in which there are pores necessary for respiration. The bark allows moisture to be absorbed from the air and protects the lichen from hypothermia or overheating. Under the bark, the hyphae are looser, with algae cells (blue-green, yellow-green or green) located between them. Usually, each type of lichen has its own type of algae. Usually photobiont cells are concentrated along the periphery - closer to the light - forming a photosynthetic layer.
slide 3
Diversity of lichens
slide 4
crustose lichens
According to the structure of the body (thallus), scale (crustal), leafy and bushy lichens are distinguished. The vegetative body of scale lichens is the most primitive, it can be granular, porous or in the form of crusts.
slide 5
foliose lichens
More developed are foliose lichens, which look like more or less dissected plates.
slide 6
fruticose lichens
Bushy lichens are highly organized, having the appearance of bushes, hanging threads or upright outgrowths.
Slide 7
Lichen reproduction
Reproduction of lichens is carried out by sexual and asexual (vegetative) methods. As a result of the sexual process, spores of the lichen fungus are formed, which develop in closed fruiting bodies - perithecia, having a narrow outlet at the top, or in apothecia, wide open to the bottom. Germinated spores, having met an alga corresponding to their species, form a new thallus with it. Vegetative propagation consists in the regeneration of the thallus from its small sections (debris, twigs). Many lichens have special outgrowths - isidia, which easily break off and give rise to a new thallus. In other lichens, tiny granules (soredia) are formed in which algae cells are surrounded by a dense accumulation of hyphae; these granules are easily carried by the wind.
Slide 8
Lichen species
Lichens grow on soil (epigean), stones (epilitic) or tree trunks (epiphytic), receiving the moisture necessary for life from the atmosphere. Some species live in the sea littoral. Settling for the first time in barren places, lichens form humus when they die, on which other plants can then settle.
Slide 9
Lichen cultivation
Lichens have even been found in the barren Arctic deserts and within the Antarctic rocks. Lichens are distributed throughout the world, but are especially diverse in the tropics, highlands and tundra. But in laboratories, lichens die quite quickly. And only in 1980, American scientists managed to “combine” an algae and a fungus grown from a spore.
Slide 10
Lichens are a source of food
Lichens are perennial organisms. They accumulate polysaccharides and fatty acids. Some substances are unpleasant in taste and smell, others are eaten by animals, others are used in perfumery or the chemical industry. Some lichens are raw materials for the manufacture of paint and litmus.
slide 11
Lichens as bioindicators
Lichens are bioindicator organisms. They grow only in ecologically clean places, so you will not find them in big cities and industrial zones.
I'm good, I know everything, I will try I will succeed.
EPIGRAPH: "THE MORE WE KNOW THE LAWS OF NATURE, THE MORE INCREDIBLE MIRACLES BECOME FOR US"
CHARLES DARWIN
Problem question.
Are there in nature
organisms made up of
independent organisms?
What is special about these
organisms?
LESSON TOPIC "LICHEN"
The purpose of the lesson: to study the features of the structure, nutrition, reproduction, significance and ecology of lichens as symbiotic organisms.
Attention! Basic concepts:
thallus
symbiosis
scale, leafy, bushy.
Algorithm.
1. Variety and distribution. Types.
2. Structure.
3. Nutrition.
4. Reproduction.
5. Distribution.
6.Value.
LICHEN
bushy
scale
leafy
Kaloplaka
Omphalina
Cladonia
I looked at the bark on the branch
Through chiseled glass:
There in the cells of the white grid
Fish sleep green.
LICHEN NUTRITION
organic matter
water and minerals
seaweed
mushroom
Klim conspired with Pakhom
Live together, in a common home:
Klim prepares salt, water,
And Pahom grain, martyr.
BREEDING
Most often by separating pieces
thallus with subsequent growth.
Special groups of fungal cells and
seaweed.
Lichens grow very slowly, growth
their range is from 1 to 8 mm per year (moss moss
grows by 1-3 mm per year).
The average age of lichens is from 30 to 80 years.
Life expectancy is 50-100 years.
GEOGRAPHY OF DISTRIBUTION
HABITAT
Lifeless Antarctica
Sands of the Sahara
polar tundra
The woods
Tundra
The mountains
bare soil
tree trunks
Sun-lit rocks
fences
Glass
blank paper
THE SIGNIFICANCE OF LICHEN
PIONEERS OF NATURE
FORM A FERTILIZED LAYER OF THE EARTH
ACCUMULATE
BIO-INDICATORS
THINK
The Bible tells of a people who wandered for many days
desert, knee-deep in the sand, all the supplies taken with them were
eaten. Many fell from exhaustion and exhaustion on
hot sand In the morning, when the sun began to glow the sand,
the wind picked up suddenly. And they saw how the sand
driven by the wind, gray lumps are rolling. Strong gust of wind
lifted them up, and it seemed that they were falling from the sky. "Manna, manna!
Manna is falling from the sky!” Everyone who still could rushed to collect this
"manna". They eagerly ate dry gray lumps, cooked porridge from them and
baked cakes.
What was this "manna" really?
Features of lichens:
The originality of the form, exchange
substances, growth characteristics and
breeding, habitat
despite their dual
nature, independent
organisms.
CHOOSE THE RIGHT STATEMENTS
1. Lichens are representatives of the plant kingdom.
2. Lichens are a single organism consisting of a fungus and algae living in symbiosis.
3. Lichens absorb water from the soil with the help of roots.
4. Lichens can be found in the forest, mountains, meadows.
5. Algae synthesize organic matter, fungi absorb water and minerals.
6. Cladonia are representatives of scale lichens.
7. Lichens grow quickly.
8. A person does not use lichens in his life.
Correct statements:
-Homework.
Everyone - pp. 102-106.
Choice task: 1. make a crossword puzzle on the topic "Lichens" (score - "4")
2. “Present the report in an interesting way (in the form of drawings, poems, etc.)
(rating "5")
Tundra plants are the basis of animal and human life. Even lichens are eaten. Moss lichen, or reindeer moss. This is one of our largest lichens, its height reaches 1015 cm. The plant resembles a fancy tree; it has a thick “trunk” and thin “branches”. Towards the ends they become thinner and thinner. If you put several of these plants side by side on black paper, you get a beautiful white lace.
When wet, reindeer moss is soft and elastic. But after drying, it becomes brittle. At the slightest touch, pieces break off from the lichen. With the help of such debris, the reindeer moss breeds. Yagel grows slowly. It increases in height by only a few millimeters per year. REINDEER MOSS
Yagel has many talents. Nobody notices him, but he does his job: he covers the roots of other plants, feeds the reindeer and their owners. Residents use reindeer moss for food, cook jellied meat from it. They say that boiled in milk, it resembles mushrooms. In times of famine, reindeer moss was added to bread. And when there were no refrigerators, meat was covered with lichen so that it would not spoil, and it was stored for a long time. European healers used to treat consumption and whooping cough with a decoction of reindeer moss, and later they forgot about it. Scientists have recently become interested in lichen. They managed to isolate usnic acid, an antibiotic, from it. It kills bacteria, and can even kill TB without harming the intestines. It is interesting that deer unmistakably find it by smell even in winter under a layer of snow.
1 slide
The purpose of the lesson: to study the systematic position, structural features, nutrition, reproduction, significance and ecology of lichens as symbiotic organisms. Attention! Basic concepts: symbiosis, thallus (thallus), fruticose, foliose, scale lichens, lichenology, lichenologist.
2 slide
Lichens are symbiotic representatives of the fungi kingdom. The science of lichens is lichenology, a lichenologist is a person who studies lichens. The internal structure of lichens: lichens are symbiotic organisms, their body consists of algae and fungus. The body or thallus is represented by intertwining fungal filaments and single-celled green or blue-green algae. Suction cups are sometimes formed on mushroom threads, which penetrate into the algae.
3 slide
Lichen nutrition: fungus filaments absorb water and minerals dissolved in it. Green algae cells in the light in the process of photosynthesis form organic substances. Lichens absorb the moisture of rains and fogs over the entire surface of the body. On hot days, they dry out so much that they seem completely lifeless, but as soon as the rain passes, they come to life again. Reproduction of lichens. Lichens reproduce mainly by pieces of the thallus, as well as by specialized cells that form inside the thallus and break it, going outside.
4 slide
Classification of lichens according to the structure of the thallus: Scale foliose fruticose lichens Kaloplaka Omphalina Cladonia
5 slide
Crustaceous lichens have the form of a crust, tightly fused with the substrate (stone, wood, etc.). Lekanora Kaloplaka
6 slide
Leafy lichens have the form of a leaf-shaped plate, horizontally spread on the substrate. Lobaria Colemma
7 slide
Bushy lichens look like upright or hanging bushes, less often unbranched upright outgrowths. Cladonia Usnea
8 slide
Lichens are found in forests, mountains, parks, squares, meadows, swamps, that is, almost everywhere.
9 slide
10 slide
Choose the correct statements: Lichens are representatives of the plant kingdom. Lichens are a single organism consisting of a fungus and algae living in symbiosis. Lichens absorb water from the soil through their roots. Lichens can be found in forests, mountains, and meadows. Algae synthesize organic matter, fungi absorb water and minerals. Cladonia are representatives of scale lichens. Lichens grow quickly. A person does not use lichens in his life. Results: 9 - 10 correct answers - well done! You did a good job. 8 - 9 correct answers - good, but you need to be more careful. Less than 8 correct answers is bad, you will have to return to this topic again.
