The role of bacteria in nature and human life Introducing different groups of bacteria and their role. Presentation on the importance of bacteria in nature and human life The importance of bacteria in nature presentation on biology

BIOLOGICAL DICTANT 1) Primitive unicellular, nuclear-free organisms are ..... 2) Bacteria that have a spherical shape are called ..... 3) Rod-shaped bacteria are .... 4) Spiral-shaped bacteria are called ..... 5) Bacteria in the shape of a comma are called .... 6) Bacteria that feed on ready-made organic substances are ...... 7) Bacteria that feed on organic substances of living organisms are classified as ..... 8) In unfavorable conditions, bacteria form ......

Louis Pasteur (1822 – 1895) Founder of medical microbiology and immunology Studied lactic acid fermentation Discovered butyric acid bacteria (anaerobes) PASTEURIZATION method (up to degrees) VACCINATION method (vaccines against rubella, anthrax, rabies)

Pathogenic bacteria DISEASE is a consequence of the activity of pathogenic bacteria. Infectious diseases: -diphtheria, tuberculosis (with sneezing, coughing) -Dysentery, typhoid fever, cholera (through water), plague (flea bites) -Anthrax, tetanus, gas gangrene (soil getting into the wound) -Botulism (in canned food, meat, fish - without access to oxygen) - Plague, glanders, tularemia - OZ

Learning new material

1. Communicating the topic and setting lesson objectives together with students (2 minutes)

To find out the topic of the lesson you need to guess the riddle: the stable is full of white sheep (teeth)…

What associations do you have in connection with the word teeth? (the teacher writes down all the words proposed by the students on the board)

What can we talk about in class? (formulation of lesson objectives together with children)

2. Updating knowledge (3 minutes)

Since the topic of our lesson is “Structure, functions and hygiene of teeth,” let's remember what we learned on this issue from past courses. You studied organ systems in 7th grade, got acquainted with the organ systems of animals, so let's remember the types of teeth in mammals.

We see that teeth are differentiated only in mammals. And their shape depends on the animal’s feeding methods. The function of mammalian teeth affected the nature of their attachment to the jaws and the characteristics of tooth replacement. Typically, mammalian teeth sit in the alveoli of the jaws and are strengthened by the connective tissue surrounding the teeth.

Note to teacher:

(the teacher uses additional material about animal teeth presented in the lesson notes in full, if the level of development of the class’s knowledge of knowledge of the class allows)

In representatives of different orders of mammals, the number of teeth varies greatly: a decrease or increase in the number of teeth is explained by the adaptation of animals to various food items. In carnivores, the number of teeth does not exceed 44, but in artiodactyls or rodents, the number of teeth varies greatly. Some edentates have 18–20 teeth; some species of marsupials can have up to 58 teeth, and representatives of the odontocetes of the dolphin family have 250 teeth. Teeth perform different functions in different orders of mammals and develop to varying degrees. So, for example, powerful canines develop in carnivores, incisors and molars develop in rodents, and canines and often premolars are lost. The function of mammalian teeth affected the nature of their attachment to the jaws and the characteristics of tooth replacement. Typically, mammalian teeth sit in the alveoli of the jaws and are strengthened by the connective tissue surrounding the teeth. In mammals, incisors, canines and premolars are replaced, and very rarely molars (in marsupials only the last molar changes). In edentate and toothed cetaceans, teeth do not change at all, and their milk teeth function throughout their lives. Only in elephants and manatees there is a constant longitudinal replacement of a worn tooth with a new one, which is laid behind the old one and gradually displaces it.

3. Human teeth, their number, classification. Changing teeth. (5 minutes)

Look at the slide, how many teeth does a person have?

Are they the same in appearance?

What are the functions of each type of teeth? How is their structure related to the functions they perform?

What do you know about baby teeth and wisdom teeth? (answers)

A person's first milk teeth appear at 6-9 months. Milk teeth have some features: they are smaller in size, have fewer tubercles and divergent roots, between which lie the rudiments of permanent teeth. The number of roots in primary and permanent teeth is the same. From the age of 6-7 years, teeth change. Their rudiments form at the roots of falling out teeth. They compress the roots of baby teeth and block the path of blood to them.

Why are wisdom teeth called that? (answers)

When a wisdom tooth begins to grow, it often does not have enough space in the existing row of teeth, which can cause complications. Improper tooth eruption can be accompanied by inflammatory diseases. When injured, infection can penetrate into the soft tissues surrounding the tooth. Inflammation can spread to deep tissues, causing periodontitis. Signs of inflammation are redness and swelling of the gums around the tooth, an unpleasant odor, and severe pain.

4. Tooth structure (3-4 minutes)

Read the textbook article on the structure of teeth, write down in your notebook the terms corresponding to the numbers on slide 11.

The tooth consists of dentin, the crown is covered with enamel, the neck and root are covered with cement. Dentin and cement are modified bone tissue.

Note to teacher: Checking the assignment of slide 11 is done by clicking on the numbers in the rectangles. The teacher's explanation for this slide is possible. As the explanation progresses, the necessary terms are gradually revealed.

5. Physical education: performing exercises while standing (stretching, etc.) to change position. (2 minutes)

5.Diseases and dental hygiene (12 minutes)

Remember from the 5th grade course what happens to rocks in the sun and frost. (answers)

5.1. Model experiment

Let's try to heat the glass in the flame of an alcohol lamp, and then lower it into water.

What happened to the glass and why?

Why can’t you immediately drink cold drinks or ice cream after a hot meal? (Tooth enamel can also crack from sudden changes in hot and cold foods. Protect your tooth enamel from sudden changes in temperature.)

5.2.Dental diseases

With dental disease, digestion is disrupted, since in this case food that is not chewed enough and unprepared for further chemical processing enters the stomach. This is why it is so important to constantly take care of your teeth. Nicotine released during smoking causes great harm to teeth and gums; Under no circumstances should you chew hard objects, and you should not drink cold water or eat ice cream immediately after eating hot food. This leads to the appearance of cracks in the enamel and caries (destruction of enamel and dentin). Bad breath appears, yellowing and destruction of enamel occurs, destruction of gum tissue around the teeth - periodontal disease. Caries is caused by bacterial plaque. Bacteria produce acid from sugar. Acid destroys tooth enamel and a “hole” is formed. Bacteria reach the pulp, affecting nerves and blood vessels. There is destruction of the pulp, inflammation of the tooth root and gum pocket. There is a danger of pus spreading throughout the body. Infection enters the body through a diseased tooth. Pathogenic microorganisms can cause inflammatory processes in the intestines, liver, etc.

5.3. Preventing tooth damage

Read the article “Healthy teeth are an important condition for maintaining human health” and make a memo for primary school students on what to do to maintain healthy teeth. Approximate rules: do not chew bones and hard candies; do not crack nuts; do not drink cold water or eat ice cream immediately after a hot meal; do not smoke, nicotine is harmful to teeth and gums; visit the dentist twice a year, etc.

5.2 Dental care

Note: By clicking on the image on slide 11 you can increase the size of the illustration. Hygiene rules can be scrolled through repeatedly by clicking on the button labeled “click”

Methods for assessing sanitary and epidemiological conditions. Spread of germs. Microorganisms. Indicators characterizing the microbial purity of air. Types of biocenoses. Characteristics of soil microflora. Microflora. Microbiological standards for drinking water. The importance of studying ecology. Properties of sanitary-indicative microorganisms. Indicators of the recency of soil contamination. Sanitary microbiology.

“Bacteria living in the human body” - Normal cohabitants in the body. Ticks. Skin. Dispersal of bacteria. Features of bacteria. Pathogenic bacteria. Diphtheria. Fighting pathogenic bacteria. Pathogens of particularly dangerous infections. Review of bacteria. Spiral-shaped bacterium. Flexibacteria. Causative agents of intestinal diseases. Interesting Facts. Irish scientists. Epidemic cerebrospinal meningitis. Anthrax carriers.

“Structure of bacteria” - Permanent structures. Oxygen. Non-permanent structures. Organic compounds. The structure of a bacterial cell. Sizes of bacteria. Staphylococci. Heterotrophs. Reproduction of bacteria. The structure and activity of bacteria. Groups of real bacteria. Vibrios. Saprophytes. Study the structure of a bacterial cell. Cytoplasmic membrane.

"Kingdom of Bacteria" - Form of bacteria. Kingdom of Bacteria. Lactic acid bacterium, or lactobacilli. Clostridia. Nucleoid. Education dispute. What bacteria are capable of photosynthesis. Shigella dysentery. Streptococcus. Escherichia coli. Method of feeding bacteria. Test. Membrane. The role of bacteria. Staphylococcus aureus. Chemotrophs. Nostoc. Bacteria that cause disease. Autotrophs. Borya helped his mother fertilize the soil with manure. Reproduction of bacteria.

“The role of bacteria in human life” - The benefits of bacteria. E. coli. Cabbage. Streptococcus is a chain of cocci. Cocci are the simplest forms of bacteria. Bacteria are cooks. Flagellum. Cottage cheese. Bacteria cause food to spoil. Kingdom of bacteria. Elongated bacteria are called rods. Milk. Vibrio. Bacteria cause disease. Harm from bacteria. Write the word “bacteria” in your notebook and draw a crown. Are bacteria harmful or beneficial? Salted cucumbers.

“Bacteria in the human body” - Flexibacteria. Disease carriers. Fighting pathogenic bacteria. Epidemic cerebrospinal meningitis. Features of bacteria. Symbiotic bacteria. Interesting Facts. Intermediate hosts of pathogenic bacteria. Causative agents of respiratory tract diseases. Compliance with personal hygiene rules. Pathogenic bacteria. Dispersal of bacteria. Skin. Species Bdellovibrio bacteriovorus. Normal cohabitants in the body.

Is it possible to exist
modern biosphere and
human in it without bacteria?

Task 2. Write the name of the forms of bacterial cells.

Bacteria of decay and decomposition

Soil bacteria

Nitrogen-fixing bacteria

Lactic acid bacteria

Lactic acid bacteria

Various types of bacteria cause food spoilage. Botulism is a disease caused by products contaminated with botulism bacilli.

Bacteria spoil the hay in the stacks. Books in book depositories suffer from them.

Pathogenic bacteria

Bacterial plant diseases

Bacterial diseases of animals and humans

Plague

Sources of infection

Cholera

Sources of infection

anthrax

Sources of infection

Tuberculosis is one of the oldest infectious diseases

Factors contributing to tuberculosis disease

Routes of infection

Prevention of infectious diseases

Answer: Life without bacteria on Earth is impossible. a) Bacteria played a key role in the creation of soil. b) bacteria decompose organic matter

"Chemosynthesis" - Methanobacteria. Some chemosynthetics (in particular, sulfur bacteria) are used for wastewater treatment. Chemosynthesis was discovered in 1887 by S. N. Vinogradsky. Chemosynthesis is... Chemosynthesis. Iron bacteria. Nitrifying bacteria. This method of obtaining energy is used only by bacteria. Information support for the lesson.

“Structure and significance of bacteria” - The cells of many bacteria have non-chromosomal genetic elements - plasmids. Bacteria play a huge role in both the biosphere and human life. Discovered in 1887 by S.N. Vinogradsky. Physiology of bacteria. Flagella. The source of hydrogen for the reduction of carbon dioxide is water. Humans also use bacteria to purify wastewater.

“Chemosynthesis of bacteria” - Molecular oxygen that appeared in the Earth’s atmosphere acted as a strong oxidizing agent. Nitrifying bacteria - oxidize ammonia to nitrates. Anaerobic chemoautotrophs. Bacteria also come into play, working with hydrogen, nitrogen compounds and methane. Back in 1887, Russian microbiologist S.N. Winogradsky discovered bacterial chemosynthesis.

“Fungi and Bacteria” - Mushrooms. Setting lesson goals and objectives, familiarizing yourself with the lesson plan. 2.Warm up. Seaweed. "The fifth is odd." Answer the questions. Repeat and summarize the knowledge acquired on the topic. 1. Organizational moment. Lesson content: Spirogyra, chlorella, ulotrix, ulva, kelp. Hyphae, mycelium, basidia, sclerotia, rhizoids.