Thing: Biology
Group: 11D,12P
Speciality: Pre-school education, Teaching in elementary grades,
The date: 22. 02. 2018
Subject: Selection basics
Target: to form students' knowledge about the role of selection in the practical activity of man, about the methods of creating various breeds of animals, plant varieties.
Lesson objectives:
Educational:
To continue the formation of students' knowledge about the selection of animals and plants.
To introduce students to the methods of selection of animals and plants.
Continue the formation of the ability to analyze and draw conclusions with an oral detailed answer.
Developing:
To promote the development of students' speech by posing a question that requires a detailed and coherent answer.
Creation of conditions for the development of oral and written speech in an individual oral and written survey.
Create conditions for the development of voluntary attention when explaining new material.
To promote the development of visual-figurative thinking when demonstrating presentations, visual materials.
Educational:
To create conditions for educating students in the correct scientific picture of the world.
To promote in students a responsible attitude to work, for the results of work.
To create conditions for educating students in positive motivation for learning through the justification of the need for the material being studied in everyday life.
To form a respectful attitude towards the work of scientific breeders on the example of the scientific activity of Vavilov N.I.
Lesson type: Lesson "discovery" of new knowledge.
Didactic goal: Achieve awareness and study of new material.
Learning technology: ICT technology, technology of problem-search learning.
Equipment: computer, multimedia projector, screen; presentation for the lesson, handout.
Basic concepts: variability, hereditary variability, cultivated plants
New concepts: selection, centers of origin of cultivated plants, law of homologous series of hereditary variability, hybridization, mutagenesis, polyploidy, inbreeding, outbreeding.
Lesson plan:
Organizing time.
Activation of mental activity of students.
III. Explanation of new material.
IV. Consolidation of acquired knowledge.
V. Summing up the lesson.
VI. Homework
During the classes
1. Organizational moment(Greeting students. Checking readiness for the lesson).
- Hello guys, today at the lesson we need to study a very voluminous material. Therefore, let's concentrate on the lesson as much as possible and work quickly and productively.
Incentive Motivation: As you know, one of the main physiological needs of a person is the need for food. This need was inherent in primitive man and modern man. In the modern world, there are many countries whose population is starving and many families do not know what will happen if their family eats for lunch. These are the countries of Africa and Latin America. The food problem is a global problem of mankind. Such a science as selection, which we will get acquainted with today, helps to solve this problem.
2. Activation of mental activity of students.
Let's remember the previous topic - "Fundamentals of Genetics", the basic concepts of genetics, by answering the questions of an interactive crossword puzzle. (presentation) (answers in groups - 2 groups are divided in advance).
3. Study of new material.
Look at the slide. What is shown here? (BIOLOGICAL DIVERSITY)
All this diversity was formed over millions of years in the course of a certain process.
What do you think what process? (evolution).
Who knows what evolution is? (the process of development of the organic world).
What do you think are the main evolutionary factors that have led to such biodiversity? (natural selection, struggle for existence).
Why is it said that natural selection plays a creative role? (new species, genera, and other systematic units appear).
All this biodiversity occurs under what conditions? Natural or artificial? (natural)
Look at the slide, what is shown here? (Demonstration of animal breeds and plant varieties).
What is the name of the science that studies the development of new breeds of animals and varieties of plants?
Announcement of the topic of the lesson. (slide) (notebook entry)
Let's try to set the goal of our lesson. ……..answers……… Let’s check the goal you set against the goal I set (slide)
(Students write definitions in a notebook)
So, let's define what is selection? Selection - from lat. "selectio" - selection. What is this science? We formulate the definition of the concept of "selection". Definition entry:
Selection - the science of improving existing ones and breeding new breeds and varieties and strainswith the necessary characteristics. (slide)
Variety, breed, strain - a set of individuals of the same species created by man in the process of artificial selection ( slide)
ACP: Now for a few minutes we will pretend that we are breeders.
First group thinks about the answer to the first task, the second group - to the second task. Time 2 minutes. (tasks for groups are given in envelopes prepared in advance)
First task: Imagine that you are breeders, you need to create a new variety of tomatoes that will be grown to make tomato juice? What traits would you give to your variety? Why?
Second task: You need to develop a new tomato variety suitable for mechanized fruit harvesting. What traits would you give to your variety? Why?
Answer: A person needs different signs for different purposes. In the first case, this palatability of tomato (1), in the second case it shape and size(2).
- How do you think, how can a person form phenotypic traits?(create certain conditions)
- Can a person influence the genotype? ( no. Our genes are our destiny. We cannot directly change our genes and our ability to grow and change. Genes determine the boundaries of our capabilities (you were born tall and you will be tall, and if you are short, then you can increase it by a maximum of 1-2 cm - pulling yourself up).
- What are mutations?(persistent change in the genotype that occurs under the influence of the external or internal environment).
- What is a mutagenic factor? And what mutagenic factors can you name? (chemical or physical agents that cause changes in the genetic material of the cell. These are ultraviolet light, x-rays, certain drugs, salts of heavy metals, caffeine, tobacco smoke. They can change the sequence of DNA nucleic acids. And such mutations turn out to be lethal or cause very serious diseases.)
Thus, A person can contribute to the emergence of mutations and select the traits he needs. This is what science does selection.
The outstanding breeder Nikolai Ivanovich Vavilov said that: "Selection is evolution directed by the will of man." (slide)
-How long do you think selection originated?
Primitive plant breeding arose simultaneously with agriculture.
The beginning of agricultural activity was laid about 10 thousand years ago, when people switched to a settled way of life, began to develop new territories, began to cultivate a number of plants and keep animals. With the transition to a settled way of life, man has made his well-being completely dependent on a limited set of plant and animal species.
What do you think, what process preceded the breeding of animal breeds?
Answer: The process of transforming wild animals and plants into cultural forms - domestication . (recording the definition in a notebook) (slide).
Widespread domestication of animals began 10-12 thousand years ago, when humanity began to move to a more sedentary lifestyle. Domestication occurred as a result of several reasons:
1) depletion of hunting grounds
2) unification of communities and tribes
3) an increase in people's need for food.
Okay, now think about what wild animals became the ancestors of domestic animals? Give examples.
The wolf is a dog, the tarpan (wild horse) is a horse, the banking chicken (wild red jungle chickens) is a domestic chicken, the wild tour (wild bull) is cattle.
Initially, selection was based on artificial selection, when a person selects plants or animals with traits of interest to him. Until the 16th-17th (16-17) centuries, the selection took place unconsciously: that is, a person, for example, selected the best, largest wheat seeds for sowing, without thinking that he was changing the plants in the direction he needed. Only in the last century, man, not yet knowing the laws of genetics, began to use selection consciously or purposefully, crossing those plants that satisfied him to the greatest extent.
Think, and answer the question: “With what sciences does selection interact very closely?” (botany, zoology, microbiology)
The scientific basis of modern breeding is genetics . The use of genetic approaches allows us to solve the following problems of modern breeding: (slide) (students read out in turn)
- increasing the yield and productivity of already existing varieties and breeds;
- breeding of new varieties and breeds;
– improvement of product quality;
- increasing the resistance of varieties and breeds to diseases;
– increasing the ecological plasticity of varieties and breeds;
- breeding varieties and breeds suitable for mechanized or industrial cultivation and breeding, etc.
A great contribution to the development of selection as a science, as I have already said, was made by the Russian scientist N.I. Vavilov. (slide). Before listening to the message, pay attention to a couple of questions that we will need to answer after listening to the message: (slide)
1. For what purpose Vavilov N.I. organized dozens of expeditions around the world in the 1920s and 1930s?
2. What conclusion was made by the scientist after analyzing the collected material?
Student's report on the fate and scientific activity of the Russian scientist N.I. Vavilov (presentation).
Discussion questions on the abstract.
- Let's see what points of origin of cultivated plants were singled out by N.I. Vavilov:
ACP: Task: Now you are invited to fill in the table based on the text on pages 118-121 of the textbook - write out the names of plants and supplement the table with those centers from the map that are not indicated in it: (10 min.). (slide with a geographical map of the centers of origin of cultivated plants).
| Centers of origin | plant name |
| 1.Indian | |
| 2. Chinese | |
| 3. Central Asian | |
| 4. Pre-Asian | |
| 5. Mediterranean | |
| 6. Abyssinian | |
| 7. Central American | |
| 8. South American | |
The time is up, let's check how you coped with the task. I show you vegetables and fruits, and you name the center of origin according to Vavilov. (slides)
Pepper - Central American
Banana - Abyssinian
Tomato - South American
Orange - Indian
Rosa - Western Asian
Lemon - Indian
- Let's do a little practical work on the study of centers of origin.
Practical work on the study of the centers of origin of cultivated plants (Appendix)
Approximately 5 minutes
Algorithm of students' activity: each in the materials there is a set of products or dishes produced from plants of the same center of origin. Everyone chooses any menu number they like.
You need:
determine which plants products are made from
write the names of these plants in the appropriate cell of table No. 2.
"Menu" on the tables:
Orange juice, rice cakes, sugar.
Cherry compote, plum juice, buckwheat porridge.
Rye and wheat bread, grape juice. Linen cloth.
Cabbage, beets, vegetable olive oil.
Macaroni, coffee, banana.
Corn flakes, chocolate. Cotton napkin.
Potato chips, tomato juice, pineapple in own juice.
- Time is over. Let's check 1-2 menus.
- Next task:
ACP: Take a contour map of the world and trace the contours of the centers of origin of cultivated plants, based on the map. (slide)
Do you have questions about centers of origin of cultivated plants?
Then let's consolidate the knowledge gained on this issue with the help of statements. You need to determine whether the statement is true or false by putting a “+” or “-” sign in front of the number.
The stage of consolidating the acquired knowledge.
Self-diagnosis of the level of acquired knowledge.
True or false statement :
If a salad of tomatoes and cucumbers is poured with olive oil, then all the components of the dish will have different centers of origin. (+)
The main component of semolina has only one center of origin.(+)
The best raw material for the production of pasta is made from wheat, the center of origin of which is located where the Blue Nile originates.(+)
N.I. Vavilov, studying hereditary variability in cultivated plants and their wild ancestors, discovered a number of patterns that made it possible to formulate the law of homologous series in hereditary variability. This law can be illustrated by the example of the Cereal family, which includes wheat, barley, rye, oats, millet, rice, corn and others.
(Handout material on the tables of students prepared in advance) Scheme 1.
Rye Barley Wheat
Corn
wheatgrass
Common ancestor of the Cereal family
N.I. Vavilov, having studied the variability of traits in plants from the Cereal family, found that out of 38 traits that are characteristic of various species of this family (color of spikelet scales and grains, awning and awnlessness, grain shape, leaf structure, color of seedlings, winter and , cold resistance, etc.), found 37 traits in rye, 37 traits in wheat, 35 traits in oats and barley, 32 traits in corn and rice, etc. Whole families of plants are generally characterized by a certain cycle of variability passing through all the genera and species that make up the family.
Assignment for students.(Appendix No. 5).
Discussion of the formulations of the law obtained from students, comparison with the correct formulation. (slide)
The law of homological series in hereditary variability according to N.I. Vavilov:
Interpretation by N.I. Vavilov. Species and genera genetically close are characterized by similar series of hereditary variability, with such regularity that, knowing the number of forms within one species, one can foresee the finding of parallel forms in other species and genera. The closer the relationship, the more complete the similarity in the series of variability.
The meaning of the law: (slide) - students are reading.
1. The law of homological series of hereditary variability makes it possible to find the necessary characters and variants in an almost infinite variety of forms of various species of both cultivated plants and domestic animals, and their wild relatives.
2. It makes it possible to successfully search for new varieties of cultivated plants and breeds of domestic animals with certain required traits. This is the enormous practical significance of the law for crop production, animal husbandry and selection.
- Let's summarize the main directions of N.I. Vavilov's scientific work. (slide)
Conclusion(students read):
Formation of tasks of modern selection.
Law of homologous series
Creation of the doctrine of the centers of diversity and origin of cultivated plants.
Development of the problem of plant immunity.
Creation of a collection of seeds of cultivated plants and their wild ancestors.
Creation of a network of institutes and selection experimental stations in the country
Do you have questions about studying the law of homologous series of hereditary variability?
Let's ask ourselves a question that we need to answer. So,what methods do breeders use? (slide)
The main selection methods are selection, hybridization, mutagenesis and polyploidization (ploiploidy). (slide) Read the definitions. (students use tables prepared in advance on the tables)
Let's consider some methods in more detail using tables.
Let us consider them in more detail and by the kingdoms of living organisms (using the tables "Breeding methods" (2 pcs).
Plant breeding methods. (slide)
The biological characteristics of plants allow in breeding work with them to use inbreeding, polyploidy, artificial mutagenesis, distant hybridization and other methods . (Working with students on tables).
Selection and hybridization are the main and traditional methods of plant breeding. Applying mass or individual selection, the breeder does not create anything new, but singles out plants with useful qualities already present in the population. Many varieties have been bred by this method, including the so-called varieties of folk selection, for example, the Antonovka apple variety, famous for its qualities.
To create plant varieties with programmed qualities, special purposeful work is carried out - the source material is selected, then hybridization followed by selection.
Using the method of hybridization with subsequent selection, breeders obtained valuable high-yielding varieties of wheat, rye, sunflower, vegetable, fruit and other crops.
Most importantly, I would like to note that the scientist-breeder Ivan Vladimirovich Michurin (1855-1935) made a great contribution to the development of the theory and practice of plant breeding (slide). He brought about 300 new varieties of fruit plants. In his works, he widely used the crossing of geographically distant forms.
- How do you understand what geographically distant forms mean?
So, for example, crossing the French pear variety Bere royale with wild Ussuri pear and growing seedlings in the conditions of central Russia, as a result of which he created the Bere winter variety (slide), combining high taste qualities of fruits with winter hardiness. The methods developed by I. V. Michurin are successfully used by breeders at the present time.
– So, we got acquainted with the basic methods of plant breeding.
Let's define what are features of plant breeding(slide) (read by students):
1) high fertility, numerous offspring
2) rapid growth and maturation,
3) the ability to reproduce by vegetative organs.
4) the presence of self-pollinating species
5) the possibility of artificial production of mutant forms, etc.
And what examples can you give of fruits, vegetables, plants obtained by selection methods? (sviti, pomelo, etc.)
Consider animal breeding methods (slide).
Do you think animal breeding methods differ from plant breeding methods? (Working with students on tables).
– Animal breeding methods are the same as plant breeding methods, but in their application, breeders have to take into account a number of features characteristic of animals.
In animal breeding, 2 types of hybridization are used. (Slide)
Inbreeding- related hybridization. Crossing between brothers and sisters or between parents and offspring leads to homozygosity and is often accompanied by a weakening of the animals, a decrease in their resistance to adverse conditions, and a decrease in fertility. Nevertheless, inbreeding is used to consolidate characteristic economically valuable traits in the breed.
outbreeding- unrelated hybridization. This crossing is accompanied by strict selection, which allows you to enhance and maintain the valuable qualities of the breed.
combination of related and unrelated hybridization widely used by breeders to breed new breeds of animals.
An important direction in animal breeding is the direction heterosis. The phenomenon of heterosis is especially widely used, for example, in poultry farming, for example, when obtaining broiler chickens.
Now, let's try to "virtual" tour among some breeds of domestic animals, and at the same time we will fix the main methods of animal breeding.
Material for the virtual tour: (slides)(students have cards with descriptions of animals on their tables, which they read aloud).
Outbreeding obtained for example,
Dogwolf - Dogs and wolves interbreed quite freely. The wolf is a shy animal with a special behavior and a developed hunting instinct. His jaws are much more powerful than those of a dog. The behavior of wolf-dog hybrids is unpredictable.
In order to tame an animal, training is required.
2. Inbreeding obtained:
Tigrolev (tiglon) is a cross between a male tiger and a female lion. They tend to be dwarfed and are usually smaller than their parents. Males are sterile, while females can sometimes bear offspring.
A liger is a cross between a male lion and a female tiger. They are the largest of the cat family in the world. Males are sterile, while females can sometimes bear offspring.
The leopard is the result of crossing a male leopard with a female lion. The head of the animal is similar to the head of a lion, while the rest of the body is more like a leopard. Leopards are larger than ordinary leopards in size, they love to climb trees and splash in the water.
Pets have a phenomenon heterosis: during interbreeding or interspecific crosses, hybrids of the first generation have a particularly powerful development and increase in viability. A classic example of the manifestation of heterosis is the mule - a hybrid of a mare and a donkey. This is a strong, hardy animal that can be used in much more difficult conditions than the parental forms.
- Let's now determine what features are distinguished in the selection of animals? (slide) (students read out in turn).
Reflection:
So, let's summarize the lesson:
What did we talk about today?
What new did you learn in the lesson?
Let's go back to the goal of our lesson, look and say, have we achieved this goal today in the lesson? ( goal- to form students' knowledge about the role of selection in practical human activities, about the methods of creating various breeds of animals, plant varieties).
Homework: Do practical work. Topic 7 Fundamentals of selection. Lesson 8. Studying the phenotypes of local plant varieties. Page 10. (Guide to laboratory and practical work in general biology)
Related lesson:"Breeding Animals and Plants".
HalinaOlga Mikhailovna
biology teacher
MBOU "Field Lyceum"
d.Polevaya -2017,
Kursk district, Kursk region
Target: to continue in students the formation of knowledge about the selection of animals and plants.
Tasks:
to continue the formation of students' knowledge about the selection of animals and plants.
To introduce students to the methods of selection of animals and plants.
continue to develop the ability to analyze and draw conclusions.
to promote the development of students' speech by posing a question that requires a detailed and coherent answer.
create conditions for the development of voluntary attention when explaining new material
Educational :
Educational :
create conditions for educating students with a correct scientific picture of the world
to promote instilling in students a responsible attitude to work, for the results of work.
educators :
Lesson type: combined
O Equipment: student presentations on the topic, books, notebooks.
DURING THE CLASSES
I. Organizational moment
II. P roverk a homework
–
Othe main task of selection, as a science?(Bringing out new and improving old varieties of plants, animal breeds, strains of microorganisms.)
–
What is selection based on??
(Genetics)
–
What is the merit of N.I. Vavilov?
(
BUTAcademician Nikolai Ivanovich Vavilov is an outstanding geneticist and breeder. It was Nikolai Ivanovich who singled out 8 centers of origin of cultural centers of plants.)
-
ToWhat are the 2 main methods of breeding?(Selection and hybridization)
– What objects are studied with the help of selection and hybridization?(animals, plants, microorganisms)
III.
Transition.
IV . Explanation of new material
Open your notebooks and write down the topic of today's lesson - "Breeding of animals and plants"
–
Primitive plant breeding arose simultaneously with agriculture. Having begun to cultivate plants, man began to select, preserve and propagate the best of them. Many cultivated plants were cultivated approximately 10 thousand years before our era.
–
Guys, if there are differences in the selection of animals and plants?
Farm animals reproduce only sexually
The offspring obtained from one pair of producers is small
High breeding value of each individual
- Farm animals reproduce only sexually, therefore, when selecting, it is important for the breeder to determine the hereditary traits that may appear in producers. The offspring obtained from one pair of producers is small, so there is a problem to preserve it as much as possible. Therefore, the breeding value of each individual is high.
- Please write down in your notebook the main features of animal breeding presented
domestication
Hybridization
–
Domestication began over 10 thousand years ago. Its centers basically coincide with the centers of diversity and origin of cultivated plants. Domestication contributed to a sharp increase in the level of variability in animals.
Hybridization and individual selection are the main methods in animal breeding. Mass selection is practically not used due to the small number of individuals in the offspring.
In animal breeding, 2 types of hybridization are used.
Inbreeding - related hybridization. Crossing between brothers and sisters or between parents and offspring leads to homozygosity and is often accompanied by a weakening of the animals, a decrease in their resistance to adverse conditions, and a decrease in fertility. Nevertheless, inbreeding is used to consolidate characteristic economically valuable traits in the breed.
outbreeding
- unrelated hybridization. This crossing is accompanied by strict selection, which allows you to enhance and maintain the valuable qualities of the breed.
The combination of related and unrelated hybridization is widely used by breeders to breed new breeds of animals.
An important direction in animal breeding is the direction of heterosis. The phenomenon of heterosis is especially widely used, for example, in poultry farming, for example, when obtaining broiler chickens.
We will learn about new types of animalsfrom student presentations:
1. Outbreeding obtained For example, dog wolf
Dogs and wolves interbreed quite freely. The wolf is a shy animal with a special behavior and a developed hunting instinct. His jaws are much more powerful than those of a dog. The behavior of wolf-dog hybrids is unpredictable.
In order to tame an animal, training is required.
2. Inbreeding obtained:
Tigrolev It is a cross between a male tiger and a female lion. They tend to be dwarfed and are usually smaller than their parents. Males are sterile, while females can sometimes bear offspring.
liger – This is a cross between a male lion and a female tiger. They are the largest of the cat family in the world. Males are sterile, while females can sometimes bear offspring.
Levopard – This is the result of crossing a male leopard with a female lion. The head of the animal is similar to the head of a lion, while the rest of the body is more like a leopard. Leopards are larger than ordinary leopards in size, they love to climb trees and splash in the water.
3. In pets, the phenomenon of heterosis is observed:
during interbreeding or interspecific crosses, hybrids of the first generation have a particularly powerful development and increase in viability. A classic example of the manifestation of heterosis ismule
- a hybrid of a mare and a donkey. This is a strong, hardy animal that can be used in much more difficult conditions than the parental forms.
V. Consolidation of acquired knowledge
questions after§3.14
V. Homework
§3.14,records
Literature:
Biology: a dictionary-reference book for schoolchildren, applicants and teachers / ed.-comp. G. I. Lermer-M.: "5 for knowledge", 2009-208 p.
Biology: a guide for students / S.V. Barabanova; under the editorship of V.L. Bykova.-M.: Enlightenment, 2009.-80 p.
Disc "Great Medical Encyclopedia" - M .: 2005
Pepelyaeva O.A., Suntsova I.V.. Lesson developments in general biology: grade 9. - M .: VAKO, 2011.-464p.
P.M. Borodin, L.V. Vysotskaya and others .. Biology .. General biology: textbook. For 10-11 cells. general education institutions: profile. Level: in 2 hours, -6th edition., Rev.-M.: Enlightenment, 2009 .- 303 p.
Biology. Introduction to general biology and ecology. \ author A.A. Kamensky, E.A. Kriksunov, V.V. Pasechnik, ed.-M.: Bustard, 2010-304s.
Plant and animal breeding methods.
Lesson type : combined lesson.
Lesson Objectives : the study of the tasks and goals of science - the selection of plants, animals and microorganisms, acquaintance with the 8 main centers of origin of cultivated plants, and the main centers of domestication of wild animals, the study of the main achievements of Soviet biologists N.I. Vavilov and his staff, the education of patriotic feelings.
Selection in the broad sense of the word means selection. But in a broad sense, selection is a complex science aimed at increasing agricultural productivity.
Selection task is to create new and improve existing plant varieties, animal breeds and strains of microorganisms.
All modern domestic plants and animals are descended from wild ancestors.
The process of converting wild plants and animals into cultivated forms is called domestication.
The main factor in domestication is artificial selection that meets human requirements.
Under natural conditions, domesticated forms usually cannot exist.
The first attempts to domesticate animals and plants were made by people as early as 20-30 thousand years BC. Domestication began with the accidental cultivation of wild animals by humans. (People began to breed rabbits only in the Middle Ages, sugar beets in the 19th century, and mint in the 20th century.)
An outstanding contribution to the development of ideas about the centers of origin of cultivated plants was made by N.I. Vavilov and his staff.
As a result of numerous expeditions, a unique, the largest collection of various cultivated plants in the world was collected.
Currently allocate 8 main centers of origin of cultivated plants .
Center name
domesticated plants
1. Indonesian - Indochinese
Bananas, sugar beets, breadfruit
2.Sino-Japanese
Rice, millet, soy, mulberry
3. Central Asian
Taiwan, Korea
Peas, flax, carrots, onions, grapes
4. Front Asian
Iran, Afghanistan, Asia Minor
Wheat, rye, barley, oats
5.Mediterranean
The coast of the mediterranean sea
olive tree, cabbage
6.African
Sesame, cotton, watermelon, coffee
7.South American
Beans, tomatoes, peanuts, pineapple, potatoes
8.Middle American
(southern Mexico)
Corn, beans, pumpkin, red pepper, tobacco
Plant breeding methods
Selection
Mass selection leads to the breeding of a whole group of individuals from the source material that have the traits desired by the breeder. (Cross-pollination in plants)
Individual selection be reduced to breeding individual individuals with traits of interest to a person and obtaining offspring from them (isolation of pure lines - homozygous individuals).
hybridization or crossing.
Crossbreeding combined with selection is one of the most effective methods of selection work.
Based on hybridization advice. Academician N.V. Tsitsin obtained valuable varieties of cereals (hybridization of wheat with rye - triticale - a fodder crop that gives high yields and is resistant to adverse external conditions.
Areas of animal domestication.
In the areas of the Indonesian-Indochinese center, dogs, pigs, chickens, geese, and ducks were first domesticated.
In the regions of Western Asia - sheep, goats.
Homework #37
Theme of the lesson "Basic methods of breeding plants, animals and microorganisms"
Target: to continue in students the formation of knowledge about the selection of animals and plants.
Tasks:
to continue the formation of students' knowledge about the selection of animals and plants.
To introduce students to the methods of selection of animals and plants.
continue the formation of skills to analyze and draw conclusions with an oral detailed answer.
to promote the development of students' speech by posing a question that requires a detailed and coherent answer.
creation of conditions for the development of oral and written speech in an individual oral and written survey.
create conditions for the development of voluntary attention when explaining new material
promote the development of visual-figurative thinking when demonstrating presentations, visual materials.
create conditions for educating students with a correct scientific picture of the world
to promote instilling in students a responsible attitude to work, for the results of work.
create conditions for educating students in positive motivation for learning through the justification of the need for the material being studied in everyday life.
Educational :
Educational :
educators :
Demonstration equipment: multimedia projector,PowerPoint presentation, photographs of animals, epigraphs printed on A4 paper.
Lesson plan:
I. Organizational moment
II. Homework check step
III. Explanation of new material
IV. Consolidation of acquired knowledge
V. Homework
VI. Summing up the lesson
DURING THE CLASSES
I. Organizational moment
– Hello guys, today in the lesson we need to study a very voluminous material. Therefore, let's concentrate on the lesson as much as possible and work quickly. So, let's remember what topic we started in the last lesson?(Selection)
- Today at the lesson we should:
- repeat the basic concepts of the topic "Selection";
- deepen the material on this topic;
- and also you must show me how hardworking, kind and considerate you are.
– Are you ready to do it?(Yes)
II. Homework check step
– So, please tell me, what is the main task of breeding as a science?(Bringing out new and improving old varieties of plants, animal breeds, strains of microorganisms.)
- Good. And tell me, what science is the theoretical basis of selection?(Genetics)
– And now think about why exactly genetic knowledge plays a big role in the development of selection?(Because the basis of the success of breeding work is largely the genetic diversity of the source material. In their work, breeders try to use the whole variety of wild and cultivated plants.)
- Correctly. The need to use in plant breeding all the species diversity of the flora of our planet was pointed out by Academician Nikolai Ivanovich Vavilov, an outstanding geneticist and breeder. It was Nikolai Ivanovich who singled out 8 centers of origin of cultural centers of plants. Let's remember what these centers are. Pay attention, cultivated plants are listed on the slide, the same task is on the cards on your tables. Your task is to write down the centers of their origin on the cards.
Students write down the centers of origin of plants in a notebook.
– Time is over. Swap cards. On the trail. The slide shows the correct answers in red. Mark with a "+" sign the correct answers, with a "-" sign the incorrect ones..
Who made how many mistakes?
Students name the number of mistakes.
– In order to continue the study of the topic, we need to repeat the main terms. We will solve a crossword puzzle with you. I have a request for you, do not shout answers from the floor, but raise your hands if you know the correct answer. the most active receive grades for the lesson. (Slides 5-12)
Questions:
Vertically:
What is the name of a plant population artificially created by man?(Variety)
What is the name of the method by which various crossings of organisms are carried out?(Hybridization)
Horizontally:
This method, which is still used today, is based on the concept developed by Ch. Darwin.
What is the name of a population of animals artificially created by man?
What is the name of a population of microorganisms artificially created by man?
– Thus, what are the 2 main methods of selection?(Selection and hybridization)
– What objects are studied with the help of selection and hybridization?(animals, plants, microorganisms)
– Do you know the methods of selection of these living organisms?(Not)
- It is today at the lesson that we will get acquainted with the features of the selection of animals and plants, the methods used in their selection, and we will talk about the selection of microorganisms in the next lesson.
- Open your notebooks and write down the topic of today's lesson -"Breeding of animals and plants"
III. Explanation of new material
– Primitive plant breeding arose simultaneously with agriculture. Having begun to cultivate plants, man began to select, preserve and propagate the best of them. Many cultivated plants were cultivated approximately 10 thousand years before our era.
Breeders have created excellent varieties of cultivated plants. And we will find out what methods they used by reading the text of paragraph 65. You have printouts on your tables with the same scheme as on the slide. Several plant breeding methods are omitted from the scheme. Your task, using the text of paragraph 65 on pages 246-252, fill in the missing columns in the table and, in addition, give an example for each type of plant crossing.
Now let's check what you wrote. Alena Ivanova, please read what you got.(Alena reads)
. That's right, here's what you should get...
– So, we got acquainted with the basic methods of plant breeding. Do you think plant breeding methods are different from animal breeding methods?(Not…)
- Animal breeding methods are the same as plant breeding methods, but in their application, breeders have to take into account a number of features characteristic of animals.
- Please tell me what are these features?
Farm animals reproduce only sexually
The offspring obtained from one pair of producers is small
High breeding value of each individual
– Farm animals reproduce only sexually, therefore, when selecting, it is important for the breeder to determine the hereditary traits that may appear in producers. The offspring obtained from one pair of producers is small, so there is a problem to preserve it as much as possible. Therefore, the breeding value of each individual is high.
- Please write down in your notebook the main features of animal breeding presented on the slide
domestication
Hybridization
Selection
– Domestication began over 10 thousand years ago. Its centers basically coincide with the centers of diversity and origin of cultivated plants. Domestication contributed to a sharp increase in the level of variability in animals.
Hybridization and individual selection are the main methods in animal breeding. Mass selection is practically not used due to the small number of individuals in the offspring.
In animal breeding, 2 types of hybridization are used.
Inbreeding - related hybridization. Crossing between brothers and sisters or between parents and offspring leads to homozygosity and is often accompanied by a weakening of the animals, a decrease in their resistance to adverse conditions, and a decrease in fertility. Nevertheless, inbreeding is used to consolidate characteristic economically valuable traits in the breed.
outbreeding
- unrelated hybridization. This crossing is accompanied by strict selection, which allows you to enhance and maintain the valuable qualities of the breed.
The combination of related and unrelated hybridization is widely used by breeders to breed new breeds of animals.
An important direction in animal breeding is the direction of heterosis. The phenomenon of heterosis is especially widely used, for example, in poultry farming, for example, when obtaining broiler chickens.
We learn about new types of animals from Anna Krasovskaya's report.
Material for the virtual tour
Today we will try to conduct a "virtual" tour among some breeds of domestic animals, and at the same time we will remember the main methods of animal breeding.
1. Outbreeding obtained for example,dog wolf
Dogs and wolves interbreed quite freely. The wolf is a shy animal with a special behavior and a developed hunting instinct. His jaws are much more powerful than those of a dog. The behavior of wolf-dog hybrids is unpredictable.
In order to tame an animal, training is required.
2. Inbreeding obtained:
Tigrolev It is a cross between a male tiger and a female lion. They tend to be dwarfed and are usually smaller than their parents. Males are sterile, while females can sometimes bear offspring.
liger It is a cross between a male lion and a female tiger. They are the largest of the cat family in the world. Males are sterile, while females can sometimes bear offspring.
Levopard - This is the result of crossing a male leopard with a female lion. The head of the animal is similar to the head of a lion, while the rest of the body is more like a leopard. Leopards are larger than ordinary leopards in size, they love to climb trees and splash in the water.
3. In domestic animals, the phenomenon of heterosis is observed: during interbreeding or interspecific crosses, hybrids of the first generation experience especially powerful development and an increase in viability. A classic example of the manifestation of heterosis ismule - a hybrid of a mare and a donkey. This is a strong, hardy animal that can be used in much more difficult conditions than the parental forms.
IV. Consolidation of acquired knowledge
Test tasks on the topic "Selection"
V. Homework
1) Paragraphs 65-66.
2) Fill in the table using the text of paragraph 66
Scientific breeders and their achievements
Methods used in obtaining the necessary features
Varieties or breeds obtained by scientists
– Thus, today in the lesson, we repeated the basic concepts of the topic "Selection", got acquainted with the methods of plant breeding and animal breeding methods
Thanks for the lesson, bye.
