The leaves of which shrub remain green until frost. Autumn changes in plant life. How plants live in winter
Municipal budgetary educational institution
Velizh secondary school №2
Excursion
"Autumn phenomena in plant life"
6th grade
Performed:
Kudryashova Ekaterina Vyacheslavovna,
biology and chemistry teacher
Goals:
educational - to develop in students the concepts of trees, shrubs and herbaceous plants, the duration of their life, the adaptability of plants to environmental conditions; autumn leaf color, leaf fall, seed dispersal, features external structure flowering plants different places habitation, preparation of plants for winter; to form a general educational skill in the preparation of a written report on the excursion.
developing - to develop curiosity, cognitive interest in the seasonal changes in nature and the creative abilities of children.
educational - to develop a dialectical-materialistic worldview, revealing the reasons for the onset of autumn phenomena in the life of plants by establishing links between them and changes in environment; to form in students an aesthetic perception of nature.
Equipment:
leaf herbarization folder;
cards - tasks;
didactic material depicting trees and shrubs;
plastic bags for collecting seeds and fruits;
magnifying glass, ruler, notebook, pencils.
Teaching methods:
observation;
conversation;
story;
object recognition.
Plan:
I. Opening speech of the teacher.
II. Independent work card students.
III. Tour results.
IV. Homework.
Conducting an excursion.
I . Teacher: Guys, here we are with you and on the spot. Look around, what time of year is it?
Students: Autumn
Teacher: Correctly! Isn't it a wonderful time of the year. How many poems have been written about him, how many pictures have been drawn, you can’t even count. Listen to I. Bunin's poem "Falling Leaves":
“Forest, like a painted tower,
Purple, gold, crimson,
Merry motley wall
It stands over a bright meadow.
Birches with yellow carving
Shine in blue azure,
Like towers, Christmas trees darken,
And between the maples they turn blue
Here and there in the foliage through
Clearances in the sky, that windows ... "
I reveal for children the secrets of the amazing things of nature.
Teacher: Guys, I asked you to find some poems, stories, proverbs, riddles on the theme "Autumn". Let's check what you have prepared.
Student:
sad time! Oh charm!
Your farewell beauty is pleasant to me -
I love the magnificent nature of wilting,
Forests clad in crimson and gold,
In their canopy of the wind noise and fresh breath,
And the heavens are covered with mist,
And a rare ray of sun, and the first frosts,
And distant gray winter threats.
(A.S. Pushkin)
Teacher: Well done! Have any of you prepared more poems?
Student 1: Poems about autumn
Already the sky was breathing in autumn,
The sun shone less
The day was getting shorter
Forests mysterious canopy
With a sad noise she was naked,
Fog fell on the fields
Noisy geese caravan
Stretched to the south: approaching
Pretty boring time;
November was already at the yard.
(A.S. Pushkin)
Student 2: Proverbs about autumn:
In autumn, cattle grow fat, and people become kinder.
Autumn is boastful, spring is fair.
Autumn will order, and spring will say its own.
Autumn is a reserve, winter is a pickle.
Autumn is harvest time.
Autumn - eight weather changes.
Buzzes like a thin fly in autumn.
In autumn, even a crow has a pile of bread.
Autumn will come, he will ask for everything.
Do not count your chickens before they are hatched.
In autumn, and at the sparrow's feast.
In autumn, even the sparrow is rich.
Autumn brings bad weather.
Student 3: Riddles about autumn:
I bring the harvest
I sow the fields again
Sending birds to the south
I undress the trees
But I do not touch pines and fir-trees.
I - ...
(Autumn)
Green, not a meadow,
Bela, not snow,
Curly but no hair.
(Birch)
Student 4:
Sits - turns green,
Flies - turns yellow,
It will fall - it will turn black.
(Sheet)
Cheerful in the spring
It's cold in summer
Feeds in autumn
Warms in winter.
(Forest)
Teacher: Well done boys! You have prepared very well.
Guys, what do you think, why do not some people like autumn?
Student: in autumn, the leaves fall, the plants fade, everything turns yellow and it rains.
Teacher: Correctly. Guys, look around, what do you see?
Student: papers, bottles, broken glass.
Teacher: all this garbage is not needed by nature. Why do you think?
Student: this garbage is not needed by nature, because it decomposes for a long time and pollutes the environment.
Teacher: Right. For example, plastic bags take about 100 years to decompose. Guys, if we came to the forest for a picnic, what should we do when we leave?
Student: We must take all the waste with us, and bury what easily decomposes.
Teacher: All right. Today we came here to find out why plants shed their leaves, why leaves turn yellow and much more. So, what changes have occurred with the change of summer to autumn?
Students: the day has decreased, the air temperature has decreased, the humidity has increased, a large number of precipitation.
Teacher: Everything is correct. What changes have taken place in plants?
Students: The grass has darkened, the leaves of trees and shrubs have turned yellow, the leaves are falling, some plants have faded, and some have already appeared seeds.
Teacher: Right.
II . Teacher: Guys, after the tour we will have to answer the questions: Why seasonal changes weather conditions affect plant life in autumn and how plants adapt to changing conditions external environment And how do they prepare for winter?
In order to answer all these questions, we need to complete a number of tasks. For work, we need to divide into 5 groups of 4 people each and each group receives its individual task on a card.
Assignments involve the performance of two types of work:
First view work is aimed mainly at familiarizing students with the variety of types woody plants, identification of signs of adaptability of plants to autumn conditions.
Second view work is aimed at the formation of aesthetic values of nature.
Before completing the assignments, I conduct a briefing.
I give an example of 2 cards (there were 5 in total).
Card 1
To study the process of leaf fall.
1. Note the changes in the life of trees, shrubs, herbs. What was the color of most plants, and which plants remained green until the frost.
2. Mark in the table the types of plants and the timing of their leaf fall: partially dropped, completely freed from foliage, left for the winter (+).
leaf fall
Plant
Partially dropped
Completely dropped
Left for the winter
3. Using a magnifying glass, examine the base of the petiole of the fallen leaf and find the layer of tissue that contributed to its separation.
4. Collect leaves of various colors and make a herbarium out of them with signatures of plant names.
5. Consider the color of the leaves of various trees and shrubs and enter the data in the table.
leaf coloring
plant name
leaf coloring
6. Is the duration of leaf fall the same for different types trees and shrubs?
7. Write a short story on the topic: "Autumn."
Card 2
Explore the variety of fruits.
1. Collect fruits that are spread by the wind (ash, maple, linden, birch).
2. Collect fruits that are distributed by birds (mountain ash, viburnum, elderberry).
3. Collect fruits that are spread by man (string, gravel, plantain, chamomile, burdock).
4. Collect fruits that spread by self-spreading (acacia).
5.Fill in the table.
plant name
fruit type
Features of the structure of the fetus
Distribution methods
Oak
acorn
Brown, surrounded by a plus sign.
With the help of animals and humans
6. Why do plants form hairs and wings on fruits? What is it connected with?
7. Make 2 syncwines on the theme: "Autumn".
When summing up in a generalizing conversation, I find out how students learned the material on this topic.
So, guys, come up to me and answer the question: When does the calendar and astronomical autumn begin?
Students: calendar autumn begins on September 1, and astronomical - after September 23.
Teacher: And botanical autumn always comes somehow unexpectedly with the appearance of massive yellowing of the foliage of birch and linden. However, real autumn comes not even when all the leaves on the trees turn yellow, but from the time when the leaf fall begins. Why do you guys think this phenomenon is very important for plants?
Students: It is during this period that the plant prepares for an unfavorable period - winter. It is with the fall of the leaves that evaporation decreases.
Teacher: What would happen if the leaves didn't fall?
Student: With the preservation of foliage, evaporation would continue, the roots could not compensate for the loss of moisture due to freezing of the soil, and this would lead to the death of the plant. Dropping leaves protects the plant from mechanical damage, because. Under the weight of snow on a wide leaf blade, the branches would break. Together with the leaves, the plant removes harmful substances, which by autumn from trunks and stems turn into leaves.
Teacher: Everything is correct. Tell me, guys, is the duration of leaf fall the same for different types of trees?
Students: No, she's different.
Teacher: But what about leaf fall?
Students: By autumn, special small cells resembling a cork are formed at the base of the leaf petiole - this is a separating layer.
Teacher: What is the name of the place on the stem where the leaf was attached?
Student: This place is called a leaf scar.
Teacher: during the period of leaf fall, the leaves change their color to yellow, red, purple, what explains this variety of colors?
Students: This is due to the fact that in addition to chlorophyll, there are other coloring substances in the leaves. But in spring, the green pigment covers them and prevents them from appearing. In autumn, chlorophyll is destroyed and another substance begins to predominate - anthocyanin, from which the leaves turn red or purple.
Teacher: Well done guys, you're right. Why do you think coniferous trees do not shed needles for the winter?
Student: Pine and spruce are drought-resistant plants, the evaporating surface of their needles is very small and they are covered with a wax coating, which almost does not let moisture through.
Teacher: At the end of the conversation, I note smart, observant, organized guys.
So, guys, today we did a great job with you, we watched how plants prepare for winter, leaf fall.
I conclude by giving the material integrity.
IV
.
I remind you of the deadlines for a written report. Each group
schoolchildren presents a completed report on the excursion, in which, in addition to the results of observations, they record personal impressions based on sensory perception of the surrounding nature.
Based on the results of the excursion, I conduct a generalizing lesson. For this lesson in the biology classroom, I am mounting an exhibition of the most successful creative works students: essays - miniatures, poems of their own composition, drawings, collections of fruits and seeds, herbarium sheets, crafts made from natural material.
Children express their admiration for natural phenomena, their feelings, love in drawing, in writing poetry, syncwines, crossword puzzles, essays, stories.
Reports are reviewed and evaluated by:
In a generalizing lesson, we summarize the tour of the two types of work provided for in the cards. The guys read their answers to questions, show drawings, read poetry, exchange opinions, and lead discussions.
The experience of holding such discussions shows the role and importance of excursions: the guys become more active, more interested in the material being studied and discussed, they share their observations and impressions with pleasure. Observing the picturesque corners of nature, schoolchildren learn to understand beauty, they develop a love for Russian nature.
Excursions give good material for the education of aesthetic feelings, a materialistic worldview, dialectical understanding, ecological ties, the unity and integrity of natural complexes.
Sources
Pasechnik V.V. Biology, mushrooms, plants. Grade 6: textbook. for educational institutions. - M .: Bustard, 2010.
Internet resources:
1. A.S. Pushkin "Already the sky was breathing in autumn"
2. A.S. Pushkin "The Sad Time"
3. I. Bunin "Leaf fall"
4. proverbs about autumn
5 . riddles about autumn
Research methods in biology. Since ancient times, people have studied the nature around them, using various methods(from the Greek "methodos" - a way of knowing, a way). The main methods include observation, experiment (experiment) and measurements.
Observation is the perception of natural objects or phenomena with the help of the senses. In the course of observing an object or phenomenon, a person only fixes the results, without interfering in the process itself. For example, observations of seasonal periodic phenomena in the life of plants and animals that are studied by phenology (from Greek words“Faino” - I also manifest “logos”).
Experiment - observation under specially created and controlled conditions, which allow you to establish how certain conditions affect an object or phenomenon. For example, we can set up an experiment that will allow us to find out what conditions are necessary for the germination of seeds different plants.
The results obtained in the course of observations and experiments must be verified and confirmed by new observations and experiments. Only then can they be considered scientific facts.
When conducting observations and experiments, measurements are always taken. Each of you has repeatedly measured the length and width of bodies, time, temperature, distance, speed of movement, etc. It is the analysis and comparison of measurements obtained during observations and experiments that make it possible to identify certain patterns.
You will get acquainted with other methods of biological research in high school.
Devices and tools. In modern biological laboratories, a wide variety of, sometimes very complex and expensive, devices and instruments are used (Fig. 4). At school, when conducting observations and experiments, you will also use various instruments, tools and equipment. Many of them are familiar to you, you will meet others for the first time (Fig. 5). When conducting laboratory work in the school biology classroom, it is important to use the equipment available correctly and strictly follow the safety rules when working with it.
Rice. 4. Modern biological laboratory
Rice. 5. Devices and instruments of biological laboratory
Safety in the biological room
- Accurately follow all the instructions of the teacher when conducting a laboratory or practical work, without his permission, do not perform any work independently.
- Carefully study the content and procedure for conducting laboratory or practical work, as well as safe methods for its implementation.
- Prepare for work workplace, put away foreign objects. Devices and equipment should be placed in such a way as to prevent their falling and overturning.
- Check the serviceability of equipment, instruments, the integrity of laboratory glassware and glassware.
- When heating a liquid in a test tube or flask, use special holders (tripods), do not point the opening of the test tube or the neck of the flask at yourself and your comrades.
- To avoid burns, it is forbidden to take heated dishes with liquids with unprotected hands.
- Be careful when handling piercing instruments, glassware and laboratory glassware, do not throw, drop or hit them.
- In the event that laboratory glassware or glassware breaks, do not collect their fragments with unprotected hands, but use a brush and a scoop for this purpose, after informing the teacher.
- If a flammable liquid is spilled and it catches fire, immediately inform the teacher about it and, at his direction, leave the room.
- In case of injury, inform the teacher about it, immediately provide first aid to the victim, if necessary, send the victim to the nearest medical facility.
- At the end of the work, put the workplace in order, hand over the instruments, equipment, materials to the teacher and, if necessary, wash your hands thoroughly with soap and water.
New concepts
Research methods. Observations. Experiment. measurements
Questions
- What methods of research in biology do you know?
- How is observation different from experiment?
- What does phenology study?
Quests for the curious
Biological knowledge and skills will be useful in your Everyday life. They will help you understand and love surrounding nature skillfully use and increase its wealth. It's very important to know natural conditions and the plants of the area where you live. You will acquire this knowledge not only in the classroom, but also on excursions, during experiments and observations. Phenological observations should be made all year round. They will help you better understand the features of the development of nature and determine the timing of work in the garden, in the garden, in the field.
Carrying out phenological observations of changes occurring in plant life in autumn
- Observe which plants change the color of the leaves, what is it like in different plants (Fig. 6).
- Note which plants have leaves that remain green until frost.
- Observe how long leaf fall lasts for different plants.
- Regularly write down in a notebook all the changes in the life of plants. Compare your observations with those of other students in the class. Discuss them. Draw your own conclusions.
Rice. 6. Autumn leaf color
Rice. 7. Planting trees by schoolchildren
Continue phenological observations of changes in plant life in winter and spring. Take part in autumn plantings trees and shrubs (Fig. 7).
1 option
1. Write down the numbers corresponding to monocot plants:
No. 1 - fibrous root system
No. 2 - two cotyledons
No. 3 - one cotyledon
No. 4 - pericarp
No. 5 - seed peel
No. 6 - one germ layer
No. 7 - two germ layers
2. Define the concept: node, internode
I. petiolate
A. birch
B. maple
B. Currant
G. Aloe
D. Ryabina
E. Oats
G. Corn
I. Simple
A. Linden
B. Rosehip
B. Wheat
G. Clover
D. Oak
E. Acacia
5. The skin of the sheet is a fabric:
A. Pokrovnaya
B. Mechanical
B. Conductive
G. Spare
6. Light sheet, unlike shadow sheet:
A. Has a lighter color
B. Contains less chlorophyll
B. Has several layers of columnar cells
D. All statements are true
7. Write down the numbers corresponding to:
I - columnar tissue,
II - spongy tissue.
No. 1 - cells are adjacent to the upper skin
No. 2 - cells are rounded and irregular shape
No. 3 - the cells are tightly adjacent to each other
No. 4 - elongated cells
No. 5 - intercellular spaces are filled with air
No. 6 - there are especially many chloroplasts in the cytoplasm of cells
8. Find a match. Write down the numbers indicating the modifications of the leaves characteristic of plants (letters).
A. barberry
B. cactus
B. Peas
G. sea buckthorn
D. Rosyanka
No. 1 - thorns
No. 2 - needles
No. 3 - spikes
No. 4 - mustache
No. 5 - hairs with sticky liquid
Option 2
1. Write down the numbers corresponding dicot plants:
No. 1 - tap root system
No. 2 - two cotyledons
No. 3 - one cotyledon
No. 4 - pericarp
No. 5 - seed peel
No. 6 - one germ layer
No. 7 - two germ layers
2. Define the concept: shoot, leaf
3. Find a correspondence between the names of plants and the type of leaf arrangement they have:
I. Sedentary
A. birch
B. maple
B. Currant
G. Aloe
D. Ryabina
E. Oats
G. Corn
4. Find a match. Which plants have simple leaves and which ones have compound leaves.
I. Complex
A. Linden
B. Rosehip
B. Wheat
G. Clover
D. Oak
E. Acacia
5. Conductive leaf bundles consist of tissue cells:
A. Mechanical
B. Conductive
B. Mechanical and conductive
G. Reserve
6.Shadow sheet, unlike light sheet:
A. Has a darker color
B. Contains more chlorophyll
B. Has one layer of columnar cells
D. All statements are true
7. Write down the corresponding numbers indicating the characteristics of the leaves of plants in wet and dry places.
No. 1 - large leaves
№ 2 – small size leaves
No. 3 - dense pubescence leaf blade
No. 4 - a large number of stomata
No. 5 - wax coating on outside sheet
No. 6 - a small number of stomata
Plants of wet places - No. ...
Plants of arid places - No. ...
8. Fill in the missing words.
1. Trailing cells, in the cytoplasm of which are ..., and the gap between them form ...
2. Penetrates into the leaf through the stomatal fissure ... and happens ...
Key
1 option
1. 1,3,6
3. A, B, C, D
4. A, B, D
5. A
6. G
7. I- 1,3,4,6 II- 2.5
8. A-3, B-2, V-4, G-1, D-5
Option 2
1. 1,2,5,7
3. G, E, F
4. B, D, E
5. In
6. G
7.I-1.4; II- 2,3,5,6
8. chloroplasts, stomatal apparatus;
Carbon dioxide, photosynthesis
Every season is beautiful in its own way. The weather outside the window renders big influence to all living things that surround us. Therefore, winter and spring, and summer, and autumn play big role in plant life.
Spring
Plants blooming in spring
In spring the days become longer and Sun rays everything is warmer. It is during this period that absolutely all plants begin to grow, bud and reach for sunshine. In order for the plant growth to be progressive, frequent and abundant moisture is necessary, especially if the zama was not snowy.
The very first spring flowers are small-beamed, for example, galanthus, dwarf irises, crocuses, chionodoxes and pushkinias.
And in April, daffodils, botanical tulips, hyacinths, as well as Siberian blueberries and imperial hazel grouse begin to bloom.
Closer to May, beautiful perennials bloom: primroses, oak and buttercup scillas, forest corydalis and sugar lungwort.
Shrub life also recovers in spring. The earliest are: wolf's bast, forsythia, red elderberry and Japanese spirea. Toward the middle of spring, Japanese quince, holly mahonia, steppe almonds and three-lobed louiseania begin to bloom.
May is the most colorful month in plant life. Bulbs begin to bloom - tulips, daffodils, Muscari mouse hyacinth. The decorative onion and the giant onion strike with their beauty.
Also representatives spring flowering are forget-me-nots, daisies, violas. And closer to summer, the following come into play: bergenia, snow-white lily of the valley, brunner, dicentra and doronicum.
Of course, it is worth noting the trees that bloom in the spring - apricot, apple, pear, cherry, plum and many others.
Summer
plant life in summer
Summer is the peak of life for almost all plants. Warm weather, long sunny days and moisture contribute not only to favorable growth, but also the ability to accumulate useful material to get through the winter.
Already in the summer, tulips, camellias, cyclamens, hyacinths and daffodils begin to prepare for the next bloom, gaining strength and energy in the summer.
This time of the year is the flowering period for many varieties: prickly cleoma, roses, ever-flowering begonias, nasturtium, gazania, snapdragon, marigolds and petunias. They delight with their colors and aroma: mignonette, smolevka, mattiola, clarkia, gazania and many other flowers.
Shrubs that bloom in the summer are very beautiful - budlea, jasmine, spray rose, small hydrangea, rhododendron and spirea. Careopteris, calicanth, oleander, cinquefoil, cistus, tannery and cletra - all these shrubs bloom in the warm summer period.
At the beginning of summer, cornflowers, bluebells, chamomiles grow and bloom in the meadows, and raspberries appear on the forest edges. Pitchers are visible on the ponds. Strawberry fruits begin to ripen, and the first mushrooms appear.
In the middle of summer, the air is saturated with the aromas of blooming linden trees. And cherries, raspberries, blueberries, currants and gooseberries are covered with numerous fruits.
Autumn
Change of plant life in autumn
For almost all plants, autumn is a period of calm or the end of the life cycle. sunny days becomes smaller and the air temperature gradually decreases. annual plants such as, peas, cauliflower, dill and others finish their growth and dry up. The same thing happens with annual flowers - calendula, ranunculus, flax, forget-me-nots and others.
In autumn, birch leaves turn light yellow, mountain ash - crimson-red, aspen - orange, and alder - dull green. Most trees shed their colorful foliage.
The color of grasses also acquires a special pigment. Blueberries and goutweed turn purple, while blueberries turn bright yellow.
Leaf fall is an integral and not insignificant part of plant life. The cover formed by fallen leaves protects the trees from winter frosts and saturates the roots with useful substances.
Not all trees shed their leaves, for example, pine, spruce and juniper are evergreen species. Also in the cold season, heather, wild rosemary, cranberries, lingonberries and other plants remain green.
Trees prepare for winter by developing protective substances on their branches - leathery scales, hairy cover and resinous, waxy substances.
Survive the winter and start life cycle lingonberries, wild rosemary, dandelion, daisy, celandine, lungwort, plantain are capable of spring. In the form of bulbs, coltsfoot is preserved. And in the form of seeds, woodlice, yaruta, shepherd's bags, swans and stinging nettles remain.
Winter
How plants live in winter
Winter is the most difficult period in plant life. In autumn, preparations for cold weather, winds and snow take place, the chemical composition trees and shrubs. Fallen leaves protect the roots from frost and saturate the plants with nutrients.
Annual plants do not live to winter period, and perennials have time to prepare. The snow cover becomes for them a kind of blanket that can keep warm and maintain moisture levels.
Plants that have shed their leaves go into hibernation. And evergreen species: fir, spruce, pine, juniper, cedar - do not fall asleep, but live due to the fact that their needles contain a sufficient amount of moisture and minerals. This allows them to survive the most severe frosts.