Biology tutors for students. Lectures on Biology A Brief Guide to Biology for Students

Private teacher Experience 6 years

from 1 400 rub / hour

free Contact

biology tutor

I prepare students for exams (OGE and Unified State Examination / admission to universities) in biology and chemistry! I guarantee that I will give 100% so that you succeed Expand pass an exam / write a test or score the required score for admission! I also do my best to make the classes interesting, with different types assignments/videos! For successful cooperation, you also need to give your best to the full program! Do your homework and try to understand / ask questions! Contact us! I will be glad to help you achieve your goal / pass the exam / understand some topic in chemistry and (or) biology! PS - I also conduct psychological consultations! (-: 4.5 years of experience in the helpline, more than 6 years of experience in psychological counseling in general (Skype, counseling in chats, public pages, e-mail counseling, and so on!). The topics of appeals can be very different - a difficult situation, entangled in oneself / in relationships with loved ones, a crisis state (loss of reference points and meanings), losses, searching for oneself and one's own path, establishing an optimal regimen / lifestyle, and so on!) Contact us!

Thanks a lot Alexandra! Her skill and approach deserves a rating of 5. The daughter is delighted from the first lesson. Studying the subject, goes not only according to the textbook, but Expand knowledge from additional books is added. Consolidation and repetition of materials is so understandable and intelligibly conveyed to the child. Thank you very much Alexandra!!! for a professional approach! All reviews (25)

OGE (GIA) USE school course University course Anatomy Biochemistry Botany +10 Genetics Zoology Microbiology Molecular biology Animal morphology pathological physiology Topographic anatomy Topographic surgery Physiology plant physiology

Schoolchildren of 6-11 grades students

m. Babushkinskaya

Maria Andreevna

Private teacher Experience 8 years

from 1 600 rub / hour

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biology tutor

At the tutor, remotely

I also conduct classes in mini-groups of 2-3 people.

Maria Andreevna is a wonderful teacher. Her classes are very rich, she manages to give a lot of material, and at the same time the student is interested in everything Expand is mastering. It is always a pleasure to talk to her, she is always friendly and in a good mood. Thanks a lot!!! All reviews (18)

Anastasia Vladimirovna

School teacher Experience 7 years

from 1 500 rub / hour

free Contact

biology tutor

At the tutor, at the student, remotely

I am an active graduate student at Moscow State University. M. V. Lomonosov, I have two higher educations, one of which is pedagogical. Currently working Expand at a private school. I specialize in medical training. My students entered Moscow State University (Faculty of Fundamental Medicine, Biological, Psychological), Moscow State Medical University. THEM. Sechenov, Russian State University of Oil and Gas, Russian National Research Medical University named after N. I. Pirogov. The best USE result: 93 points in biology, 91 in chemistry. As a postgraduate activity, I conduct classes for students of 1-2 courses of natural science faculties.

A good young teacher, focused on results. There is a lot of knowledge in chemistry and biology, which Anastasia Vladimirovna shares openly and with pleasure. Expand Sets homework, discusses solutions and is always in touch. Due to the personal heavy workload in obtaining a candidate's degree and a second higher education it was not always possible to reschedule the lesson in advance, arrive on time, or go on Skype (if there was such an agreement). In general, an excellent and correct teacher who will mentally set up your child for the best and give good knowledge. All reviews (13)

Schoolchildren in grades 5-11 Students Adults

m. Nagatinskaya

Daria Valerievna

Private teacher Experience 11 years

from 1 100 rubles / hour

free Contact

biology tutor

At the tutor, remotely

Candidate of Biological Sciences. I work at the Institute of Biomedical Sciences Russian Academy Sciences. Graduated with honors from the post-graduate course of the Institute Expand biomedical problems, main directions scientific activity: marine and space medicine, microbiology, histology, zoology, embryology. Winner and prize-winner of olympiads in chemistry and biology. I passed the exam in chemistry, the result: 94 points. There is extensive experience in preparing for the Unified State Examination, the OGE, olympiads, including the Moscow State University olympiads. I try to find an individual approach to each student, depending on his level of knowledge, the desired result and the characteristics of character and learning. I think that there are no untrained students - there is an incorrectly chosen methodology. I also consider it important to arouse interest in the subject, since I myself am passionate about the subjects that I teach, and I do it with pleasure. I studied English at the Moscow Institute of Linguistics and, by virtue of professional activity participated in numerous international conferences, negotiated in English, has experience in using English in contract and accounting activities, since the Institute of Biomedical Problems is a world and recognized leader in the field of space biology and medicine and cooperates with many foreign organizations. Come - and your dream will become a reality!

My daughter went to classes with Daria Valerievna for two years. The goal was to prepare for the exam in chemistry and biology. We are very pleased and grateful to Daria Valerievna. Expand Not to mention good preparation - my daughter has a solid A in the certificate in both subjects, the best result at school in the Unified State Examination in Chemistry, I want to say how much the teacher finds a common language with the children !!! My daughter went to classes with pleasure, they developed wonderful friendships. At any time, the daughter could ask a question and always received understanding and answers to all questions. Once again I will say - we are very pleased that we got to Daria Valerievna, many thanks to her for everything !!! All reviews (1)

Zosim Nikolaevich

Private teacher Experience 9 years

from 750 rub / hour

free Contact

biology tutor

At the tutor, at the student, remotely

We studied chemistry with Zosim Nikolayevich for four months, we were very satisfied. For that a short time scored the points we need for admission Expand in high school, were engaged twice a week. Patient, explains the topic in an accessible way, disassembles until his student understands. Thank him very much! All reviews (51)

biplab

And Experience 16 years

from 3 000 rub / hour

free Contact

biology tutor

At the student

Multi-learning methods English language- a combination of several disciplines, different teaching materials as well as a modern audio-video teaching method Expand (via Apple iPad), etc. Training is conducted according to an individual program in each case. Teaching methodology combines elements of traditional and communicative techniques, includes the development of oral and written speech, the rapid expansion vocabulary, learning grammar. great attention is given to pronunciation and the development of listening comprehension. Modern textbooks (British or American), as well as the most important "Neutral English Accent", are used. For adults: from Basic English Grammar, Wren and Martin English High School Grammar & Vocubulary, Philip Gucker - Essential English Grammar, Peter Watkins-Essential English. Essential Grammar in Use by Hicks, Business English on VOA - Based on the voice of Special American English with Interactive courses, Streamline, Headway, Business English, Round up, OXFORD University and CAMBRIDGE University English all Courses (Grammar, Vocabulary, Idioms, Phrases etc. for Chief/Beginner, Pre-intermediate, Intermediate, Upper Intermediate & Advanced), Business English & Spoken english and even special audio-video learning programs (via Apple iPad), etc. For directors: Beginner English, Murthy level Raymond "English in Use New 3Ed", English WORKBOOK (Part-1,2,3, etc.) PUPIL'S BOOK by Elizabeth Gray- Virginia Evans, special audio-video learning programs (via Apple iPad), etc. The main task - to have a result! A creative approach to the learning process. free Contact

biology tutor

At the tutor, remotely

I am a tutor in biology and chemistry. I have been studying biology in depth since 2007. My results: Winner of the All-Russian Olympiad for School Students Expand in biology (2012); finalist of the All-Russian Olympiad for schoolchildren in biology (2012) medical University PMGMU them. I.M. Sechenov, specialty pediatrics. I have been tutoring for 2 years. Main areas of training: Unified State Examination, OGE. Preparation for admission to specialized medical classes. Preparation for participation in biology olympiads, from urban to international levels. medical universities to "budget". Moscow and other cities. Admission to the Faculty of Psychology of Moscow State University. M. V. Lomonosov. Moscow. Admission to veterinary academies. Moscow and other cities. Author's training programs have been developed for each direction. Results: The average score of my USE students in biology is from 80 to 93 points. My students entered such universities in Moscow as: First Moscow State Medical University. I.M. Sechenov, RNIMU them. N.I. Pirogova, Moscow State Medical University named after. A.I. Evdokimova. Unified State Examination, OGE. Preparation programs for the Unified State Examination, OGE. The programs are divided into 1st and 2nd stage. The 1st stage of the program is for students with a zero level. It allows the student to raise the level of knowledge from 0 to 80 points, pass the exam without stress. The 2nd stage of the program is for those who have basic knowledge of biology . At the 2nd stage of the program, attention is paid to the nuances of the exam, subtleties, “traps” of the Unified State Exam, OGE are worked out. This allows you to get the highest possible scores on the exam. Preparation program for Olympiads in biology. I specialize in preparing for the All-Russian Olympiad for schoolchildren in biology. Every year I prepare the team of the gymnasium No. 2 in Sibay for the regional stage of the All-Russian Olympiad for schoolchildren in biology. Program for preparation for the All-Russian Olympiad schoolchildren in biology was created on the basis of the program "The Way to Olympus", Moscow State University named after M.V. Lomonosov, RKhTU im. D.M. Mendeleeva. All tutoring programs provide for the creation and maintenance of an individual training program, a personal schedule of sessions in a Google calendar, a special chat in instant messengers. Any of the programs provides for initial and intermediate sections of knowledge, performance reports.

This section contains literature on biology, zoology, physiology for medical students. You can download reference books, biology textbooks, various tasks and tests on questions general biology.

The section will be useful to students and applicants entering medical schools.

Section topics:

List of articles: "Section: Biology for students"

graduate School

modern biology

Teacher of the highest qualification category. My students are students and graduates of the following universities: Moscow State University. M.V. Lomonosov (Faculty of Chemistry, FFM, Faculty of Biology, FNM, Faculty of Psychology); University of the Ministry of Internal Affairs of Russia (Faculty of Psychology); Moscow State Pedagogical University (Chemical Faculty, Faculty of Biology); RCTU them. DI. Mendeleev; Yaroslavl State Medical Academy; RSMU im. N.I. Pirogov; MGMU them. THEM. Sechenov; RUDN (Faculty of Medicine); Kazansky federal university; MITHT them. M.V. Lomonosov; MGMSU them. A.I. Evdokimova; GKA them. Maimonides; MVA them. K. I. Scriabin; III Med. College; V Med. college. The main results of the work: - in total, at the beginning of August 2017, 108 students entered universities (1 student passed the USE with 100 points in 2013; 2 students passed the USE with 100 points in 2014 and 1 student in 2015; average primary score USE students in 2017 92. prepared 11 winners All-Russian Olympics in chemistry, from district to city stages).

Education

2000, Vologda State Pedagogical University

Natural Geographic, Chemistry and Biology Teacher high school

An experience
teaching

Tutoring experience since 1996

Latest review

I want to thank Vladimir Alexandrovich for preparing my daughter for passing the exam and admission to the university. Chemistry began at the beginning of the 11th grade. The tutor was recommended to us by friends, later we read a lot of good reviews on the Internet. At the first lesson there was a test, according to the results of which Vladimir Aleksandrovich determined the level of training and recommended the required number of lessons per week. A teacher who is very loving and knows his subject very well, easily and clearly explains complex material, correctly identifies gaps in knowledge and pays increased attention problematic issues. Classes are easy and interesting, despite the very large volume of tasks. The only necessary condition for obtaining a high result is the personal interest of the student, and not just his parents, and the willingness to perform a lot of tasks. Thanks to classes with this teacher, the daughter became the winner of two chemistry olympiads, passed the exam with 100 points, confirming this result by successfully passing an additional entrance test in chemistry when entering Moscow State University. Lomonosov. The result of classes with such an experienced teacher was the passing scores required for enrollment in the 1st wave in all selected specialties of three medical universities in Moscow and medical. Faculty of RUDN University, as well as RCTU. We had a choice! Now my daughter is a student of the Faculty of Fundamental Medicine of Moscow State University. Lomonosov. Many thanks to Vladimir Alexandrovich! I wholeheartedly recommend this instructor.

Anatoly Vladimirovich is a teacher, of which there are few now, he knows his subject thoroughly, after a short interview he immediately finds weaknesses. Helped my daughter to prepare for the exam in biology. He is a professional and explains everything very clearly. But the main thing is that it was always interesting in the classroom, and my daughter passed the exam. We are very pleased with the result, although we expected more appreciated, but it is our fault that we turned to him so late. Thanks a lot for the preparation!

Vera Mikhailovna 06/27/2019

As a teacher, Anatoly Vladimirovich is a true professional - a competent, demanding biology tutor. Explains clearly, teaches to quickly learn great amount information and teaches how to cope with a large number of tasks without difficulty. He personally worries about each student, is always ready to help or give practical advice. Open, very friendly, easily finds a common language with everyone. Many thanks to Anatoly Vladimirovich for everything: for the tremendous pleasure of communicating with him, and most importantly, for the knowledge, skills and abilities, which, I think, will be useful to me in the future. Classes continue and many thanks to the company for such excellent, competent teachers.

Zinaida 04/06/2019

Our daughter is an external student in grade 10-11, a tutor is needed to prepare for the exam in biology and subsequent admission to a medical university, she is on homeschooling. On your site, we have chosen a great tutor Anatoly Vladimirovich. We had many tutors during our studies, but this is the first time we see this. The atmosphere in the classroom is very comfortable and friendly; possessing such traits as kindness, sincerity, responsiveness and love for his work and subject. Anatoly Vladimirovich is able to find an approach to anyone, there is no such question that he would not be ready to answer without delay. wonderful person and worthy of attention and respect for the teacher, whom I want to follow along the path of biology and thank you endlessly for the work done and communication. We continue our work, thank you!

Galina 31.03.2019

Anatoly Vladimirovich is a sensitive teacher, dedicated to his work. He is always in search of new means and forms of education, full of strength, energy, enthusiasm and creative ideas. He successfully and effectively applies the latest in the educational process. pedagogical technologies, skillfully uses in educational and extracurricular activities creative work, actively promotes the development of the intellectual, moral, communicative potentials of the personality of each student. In his lessons, everything is thought out to the smallest detail, one task is replaced by another, and each task requires the student not just to perform mechanically, but makes him think, compare, contrast, and draw conclusions. The daughter says that during the classes he has a favorable psychological climate. Although the classes are on Skype, his presence is felt. It teaches them to look for and find solutions on their own. Anatoly Vladimirovich teaches students and is constantly engaged in self-education. A big THANK YOU to him!

Elena 04.02.2019

We are grateful to fate for bringing us together with such a wonderful person and teacher as Anatoly Vladimirovich. A true professional in his field. Gives knowledge in a systematic way individual methodology. He has a wealth of teaching experience. This is a responsible, demanding and at the same time friendly biology teacher who can find an approach to each student. My son's vision of the subject has developed into a fairly coherent system. Thanks to the presentation of material provided by Anatoly Vladimirovich, impressive results have been achieved in such a short period of time. We sincerely thank Anatoly Vladimirovich for helping us make our dream come true! We continue the lessons.

Tatyana 09.01.2019

Our daughter, a 10th grade student, is assisted in biology for admission to medical school. University Stepura Anatoly Vladimirovich. I only want to say good things about the teacher. Competent, punctual, moderately strict in terms of study, but that's even good. Classes are always interesting and fruitful, knowledge is already visible on the face. Its individual program lessons that are well received. Thanks a lot!

Yuliana 11.12.2018

Many thanks to Anatoly Vladimirovich for a worthy preparation for the exams! I got 5 points in biology and entered the top university in Moscow at the chosen faculty out of competition according to the points scored on the Unified State Examination thanks to high-quality preparation! Thank you so much!

Shashina Daria Anatolievna 10.08.2018

My daughter Anastasia was a complete loser in biology. and for 6 months the teacher not only pulled her up in the subject, but she was able to send the OGE in biology! she lacked 1 point to 4. I am satisfied with the work of the tutor.

natalya yuryevna 08.08.2018

Two years ago, my daughter was preparing for the OGE with Anatoly Vladimirovich. We are so pleased with his work that this year, without a doubt, we asked him to prepare for the Unified State Examination! Anatoly Vladimirovich presents the material in an accessible and competent way, classes are held in a warm and comfortable environment, he constantly maintains feedback with parents, thank you very much for your help and support!

Svetlana 16.03.2018

With a tutor Anatoly Vladimirovich, we are preparing for the exam. We like him, gives his information, explains. He is very responsible and treats his students individually. Clearly explains, write tests. If any questions arose in parallel, of course, he answers them. He does not have free time in class, he does not allow to be distracted by conversations on abstract topics, he quickly directs in the right direction. The tutor gives a lot of such information that it would be difficult for us to collect on our own. This is quality information that is hard to come by. He is a top notch teacher!

Ibrahim 22.02.2018

In January of this year, we started classes with Anatoly Vladimirovich. Everything is fine, we like everything very much, the child is happy. The lessons themselves are interesting, the child was drawn into the knowledge of the subject. Improving academic performance on the face .. This is a very lively teacher. He immediately aroused in the child a love of biology. The teacher works with an electronic board, he has his own methods of conducting classes that are aimed at improving knowledge and preparing for the exam. We are very satisfied! A friendly teacher, a good professional, helped our child to believe in himself. We are very grateful to him. Rating is excellent.

Elizabeth 20.02.2018

The daughter is very pleased with the classes with Anatoly Vladimirovich. The teacher is fluent in the subject, simply and clearly presents the material, classes are held in a friendly atmosphere. Previously, teachers at school presented that the child knows the subject well, but it turned out that there is something to work on and we are happy about this, thank you

Tatyana Yurievna 12.02.2018

We are very pleased with the classes with Anatoly Vladimirovich! The teacher is strong, knows his subject well and can teach the material in an accessible and interesting way, uses modern presentation technologies, tests. He managed to find a common language with the child, he is not only a good teacher, but also a pleasant person.

Olga 12/26/2017

Anatoly Vladimirovich helped me a lot, my knowledge of biology improved markedly. Classes are held in an interesting form, using visual material, he is very good-natured, I like it.

Angelina 12/25/2017

Excellent teacher! The girl was at first against classes with a man. The stereotype that a teacher should be a woman is quite persistent. A respectful attitude towards students and parents, an accessible and competent presentation of the material, building warm relationships and constant feedback, these are just a few of the qualities inherent in Anatoly Vladimirovich. We live in the countryside and it's hard to find a good tutor Skype sessions were very convenient and effective.

Svetlana 14.08.2017

I really liked the classes with Anatoly Vladimirovich. The teacher presents a sufficiently large amount of material grouped, in a system. He cares and worries about passing the test papers and exams well and provides constant support in this. At the same time, he is a wonderful and pleasant person, it is very interesting and comfortable to communicate with him.

Igor 14.08.2017

I really liked the biology classes, Anatoly Vladimirovich was able to explain the material easily and clearly. For 3 months, I perfectly prepared for the exam. I went to the exam with confidence. In addition, it was pleasant even just to communicate with Anatoly Vladimirovich.

Muhammad 17.06.2016

We love biology classes! For 1 month, the teacher managed to give a program for a whole year, he has his own methods, some developments, thanks to which the student easily learns a large amount of material. Very fruitful work! Recommended!

Nastasya Pepanyan 11.05.2016

We are simply delighted with Anatoly Vladimirovich !!!. He is always punctual and gentle. Classes are always top notch. The child is always with great pleasure studying and looking forward to classes. He knows his subject just fine. And he also teaches it. We are ready to recommend Anatoly Vladimirovich to everyone. Score him 5

Irina Ivanovna 11.02.2016

The instructor is perfect for us. Classes are always on time. There are no complaints. Daughter enjoys doing it. We rate five.

Dmitry 01/27/2016

I have been trained in:

DNU"93, Donetsk National University, majoring in Biology. (1993)

Specialization:

Preparation for the exam in biology, Preparation for the OGE in biology, Preparation for the DWI in biology, In-depth study of biology, Histology for students, Preparation for admission to Moscow State University. M.V. Lomonosov, Preparation for admission to medical universities, Preparation for admission to classes of chemical-biological and medical profiles

Shortly about myself:

Editor of the site "I will solve the exam". I will qualitatively prepare for the exam in biology and internal exams (DWI) for admission to medical universities, veterinary and agricultural academies, biological and psychological faculties of pedagogical universities and universities. I work with students of all levels...

Biology

State educational institution higher professional education

“Ryazan State Medical University named after acad. I.P. Pavlova

Federal Agency for Health and Social Development"

Department of Histology and Biology

Kalygina T.A. Bryzgalina L.I. Shutov V.I.

Biology

a course of lectures for students studying in Russian

Reviewers: Endolov V.V., professor, head. Department of Anatomy, Physiology and Human Hygiene of the Ryazan state university them. S. Yesenina Darmogray V.N., professor, head. department

pharmacognosy with a course of botany.

Modern biology, being a fundamental discipline, plays a paramount role in the professional training of various specialists, including doctors.

In the field of medical education, a broad biological training of students is necessary for them to obtain fundamental knowledge in the field of biology and medicine, is human-oriented and meets the needs of practical medicine.

The main goal of this work is to form a holistic view of the basics of biology, taking into account the modern achievements of this rapidly developing branch of science and to assist first-year foreign students in mastering theoretical knowledge to achieve the desired level in the knowledge of educational material.

The material of this course of lectures is presented in the traditional sequence in accordance with the position on the theory biological systems and ideas about the levels of organization of living nature. The material is divided into 16 topics and includes cytology, molecular biology, reproduction and development of organisms, general and medical genetics, the theory of evolution and anthropogenesis.

The main theoretical material studied in the first year is outlined. foreign students specialty "General Medicine", "Dentistry", "Pharmacy".

Introduction to the science of biology

1. The subject of biology. Classification of biological sciences.

2.Methods of studying (research) of biology.

3. Basic properties of living beings. Definition of "life".

4. Levels of organization of the living.

The subject of biology. Classification of biological sciences

The term "biology" is formed from two Greek words (bios - life and logos - teaching).

The term was introduced in 1802 by two naturalists - J. B. Lamarck and G. R. Treviranus, independently of each other.

Biology studies the general laws that are characteristic of all living things and reveal the essence of life, its forms and development.

Biology is a complex science. Sections of the science of biology are classified in the following areas:

1) the study of systematic groups (according to the objects of study). For example, zoology, botany, virology.

AT within these sciences there are narrow directions (or disciplines). For example, in zoology, protozoology, helminthology, entomology, etc. are distinguished.

2) the study of different levels of organization of living things: molecular biology, histology, etc.

3) properties and manifestations of the life of individual organisms. For example, physiology, genetics, ecology.

4) connections with other sciences (as a result of the integration of sciences). These are biochemistry, biophysics, biotechnology, radiobiology, etc.

Methods for studying biology

The main methods used in the biological sciences are: 1) observation and description - the oldest (traditional) method of biology. This me-

The method is widely used in our time (in zoology, botany, cytology, ecology, etc.)

2) comparison, i.e. the comparative method makes it possible to find similarities and differences, general patterns in the structure of organisms.

3) experience or experiment. For example, the experiments of G. Mendel or the work of I.P. Pavlov in physiology.

4) modeling - the creation of a specific model or processes and their study. For example, modeling the conditions and processes (inaccessible to observation) of the origin of life.

5) the historical method - the study of the patterns of appearance and development of organisms

The main properties of living

Living beings differ from inanimate bodies by a number of properties. The main properties of living things are:

specific organization.

Living organisms have the necessary structures that ensure their vital activity.

The specific organization of living beings is also manifested in particular the chemical composition. From chemical elements a large proportion falls on oxygen, carbon, hydrogen, nitrogen. In total, they make up more than 98% of the chemical composition. These elements form complex structures in living organisms. organic compounds- proteins, fats, nucleic acids, carbohydrates that are not found in inanimate nature.

Metabolism and energy.

Organisms constantly exchange matter and energy with environment is a necessary condition for existence.

The metabolism and energy consists of 2 processes:

a) synthesis or assimilation, or plastic exchange (with the absorption of energy). b) disintegration or dissimilation, or energy metabolism(with energy release)

Homeostasis - maintenance of constancy internal environment.

In living beings, complex self-regulating processes take place, which proceed in a strictly defined order and are aimed at maintaining the constancy of the internal environment (for example, at the constancy of the chemical composition). At the same time, the organism is in a state of dynamic equilibrium (i.e., mobile equilibrium), which is important when it exists in changing environmental conditions.

Reproduction.

Reproduction is the property of organisms to reproduce their own kind. Each creature has a limited lifespan, but, leaving behind offspring, ensures the continuity and succession of life.

The ability to develop is a change in wildlife objects.

Individual development (ontogenesis) - the development of an individual in most cases begins from the zygote (fertilized egg) or from the division of the mother cell until the end of life. In the course of ontogenesis, growth, differentiation of cells, tissues, organs, and the interaction of individual parts occur. The lifespan of individuals is limited by aging processes leading to death.

Phylogeny is the historical development of the world of living organisms.

Phylogeny is the irreversible and directed development of wildlife, which is accompanied by the formation of new species and the progressive complication of life. result historical development is the diversity of living beings.

Irritability.

Irritability is the body's ability to respond to influences with certain reactions. The form of manifestation of irritability is movement.

At plants - tropism (for example, changing the position of leaves in space due to light - phototropism).

At unicellular animals - taxis.

Multicellular reactions to irritation are carried out using nervous system and are called reflexes.

Heredity.

Heredity - the property of organisms to pass from generation to generation characteristics species with the help of carriers of hereditary information, DNA and RNA molecules.

Variability.

Variability is the property of organisms to acquire new traits. Variation creates diverse material for natural selection.

Based on the properties of living things, scientists are trying to define the concept of "life". The definition of life given by the scientist - biophysicist M.V. Volkenshtein best of all corresponds to the current state of development of biology: environment."

This definition includes signs of the living. Each cell and organism as a whole is a system, i.e. are a set of interacting, ordered structures (organelles, tissue cells, organs). Living beings are open systems that are in a state of dynamic equilibrium with the external environment. Living beings carry out a continuous exchange of matter and energy with the environment (absorption and excretion, assimilation and dissimilation).

Levels of organization of living beings

Life on Earth is an integral system consisting of various structural levels of organization of biological beings. There are several main levels of organization (the division is conditional)

Molecular genetic.

Biology starts at the molecular level, because the atomic level bears no trace of biological specificity. This level explores DNA, RNA, proteins, genes and their role in the storage and transmission of genetic information, in metabolism and energy conversion. Biology studies the laws specific to this level.

Cellular.

Structural, functional and genetic unit living beings is a cell. Viruses, being a non-cellular form of organization of living things, show their properties as living organisms only when they invade cells.

On the cellular level study the structure of cells and cellular components, self-reproduction, the implementation of hereditary information, the metabolism and energy occurring at the cell level.

Organismic.

The structural unit at this level is the organism, the individual. An organism is a system that exists independently in the environment. At this level, the processes of ontogeny take place. In the course of ontogenesis, hereditary information is realized under certain environmental conditions, i.e. the phenotype of an organism of a given biological species is formed.

Population-species.

The elementary unit of a species is the population. At this level, the exchange of genetic information during crossing, changes in the genetic composition of populations, factors affecting the dynamics of the genetic composition of populations, and the problems of preserving an endangered species are studied.

Ecosystem.

The structural unit of this level is ecosystems, which are understood as areas of the earth's surface with certain natural and climatic conditions and associated communities of microorganisms, animals and plants, which form an inseparable interdependent complex. This level studies the circulation of substances and the flow of energy, which are associated with the vital activity of all living organisms. Ecosystems make up the biosphere - the area of \u200b\u200bdistribution of life on Earth. Allocate a social level characteristic of a person.

All levels of organization are closely interconnected, which indicates the integrity of wildlife. Without the biological processes that take place at these levels, the existence of life on Earth is impossible.

Man and all mankind is an integral part of the biosphere. Human health depends on the state of the biosphere, on the ability to adapt to changing environmental conditions. If this ability is not sufficiently manifested, then disturbances may occur that affect various levels of life (cellular, organismic).

Cell is the elementary structural unit of a living organism

1.Cell theory.

2. The structure of the cell.

3. Evolution of the cell.

Cell theory.

In 1665 R. Hooke first discovered plant cells. In 1674 A. Leeuwenhoek discovered the animal cell. In 1839 T. Schwann and M. Schleiden formulated the cell theory. The main position of the cell theory was that the cell is the structural and functional basis of living systems. But they mistakenly believed that cells are formed from a structureless substance. In 1859 R. Virchow proved that new cells are formed only by dividing the previous ones.

The main provisions of the cell theory:

1) The cell is the structural and functional unit of all living things. All living organisms are made up of cells.

2) All cells are basically similar in chemical composition and exchange processes. 3) New cells are formed by dividing existing ones.

4) All cells store and implement in the same way hereditary information. 5) The vital activity of a multicellular organism as a whole is due to the interaction of its constituent cells.

Cell structure

According to the structure, 2 types of cells are distinguished:

prokaryotes

eukaryotes

To Prokaryotes include bacteria and blue-green algae. Prokaryotes differ from eukaryotes in the following: they do not have membrane organelles present in a eukaryotic cell (mitochondria, endoplasmic reticulum, lysosomes, Golgi complex, chloroplasts).

The most important difference is that they do not have a nucleus surrounded by a membrane. Prokaryotic DNA is represented by one folded circular molecule. Prokaryotes also lack cell center centrioles, so they never divide by mitosis. They are characterized by amitosis - direct rapid division.

Eukaryotic cells are cells of unicellular and multicellular organisms. They consist of three main components:

- cell membrane surrounding the cell and separating it from the external environment;

- cytoplasm containing water, mineral salts, organic compounds, organelles and inclusions;

- nucleus, which contains the cell's genetic material.

outer cell membrane

1 - polar head of the phospholipid molecule

2 - fatty acid tail of the phospholipid molecule

3 - integral protein

4 - peripheral protein

5 - semi-integral protein

6 - glycoprotein

7 - glycolipid The outer cell membrane is inherent in all cells (animals and plants),

has a thickness of about 7.5 (up to 10) nm and consists of lipid and protein molecules.

At present, the fluid-mosaic model of the construction of the cell membrane is widespread. According to this model, lipid molecules are arranged in two layers, with their water-repellent ends (hydrophobic - fat-soluble) facing each other, and water-soluble (hydrophilic) - to the periphery. Protein molecules are embedded in the lipid layer. Some of them are located on the outer or inner surface of the lipid part, others are partially immersed or penetrate the membrane through and through.

Membrane functions:

- protective, boundary, barrier;

Transport;

- receptor - carried out at the expense of proteins - receptors that have a selective ability for certain substances (hormones, antigens, etc.), enter into interaction with them chemical interactions, conduct signals inside the cell;

- participate in the formation of intercellular contacts;

- provide the movement of some cells (amoeboid movement).

Animal cells have a thin layer of glycocalyx on top of the outer cell membrane. It is a complex of carbohydrates with lipids and carbohydrates with proteins. The glycocalyx is involved in intercellular interactions. The cytoplasmic membranes of most cell organelles have exactly the same structure.

In plant cells outside of the cytoplasmic membrane. the cell wall is made up of cellulose.

Transport of substances across the cytoplasmic membrane.

There are two main mechanisms for the entry of substances into the cell or out of the cell to the outside:

1. Passive transport.

2. Active transport.

Passive transport of substances occurs without the expenditure of energy. An example of such transport is diffusion and osmosis, in which the movement of molecules or ions

is carried out from an area with a high concentration to an area with a lower concentration, for example, water molecules.

Active transport - in this type of transport, molecules or ions penetrate the membrane against a concentration gradient, which requires energy. An example of active transport is the sodium-potassium pump, which actively pumps sodium out of the cell and absorbs potassium ions from the external environment, transferring them into the cell. Pump

- This is a special membrane protein that sets it in motion by ATP.

Active transport maintains a constant cell volume and membrane potential.

Substances can be transported by endocytosis and exocytosis. Endocytosis - the penetration of substances into the cell, exocytosis - out of the cell.

During endocytosis, the plasma membrane forms an invagination or outgrowths, which then envelop the substance and, lacing off, turn into vesicles. There are two types of endocytosis:

1) phagocytosis - the absorption of solid particles (phagocyte cells), 2) pinocytosis - the absorption of liquid material. Pinocytosis is characteristic of amoeboid protozoa.

By exocytosis, various substances are removed from the cells: undigested food residues are removed from the digestive vacuoles, their liquid secret is removed from the secretory cells.

Cytoplasm - (cytoplasm + nucleus form protoplasm). The cytoplasm consists of a watery ground substance (cytoplasmic matrix, hyaloplasm, cytosol) and various organelles and inclusions in it.

Inclusions are waste products of cells. There are 3 groups of inclusions - trophic, secretory (gland cells) and special (pigment) values.

Organelles are permanent structures of the cytoplasm that perform certain functions in the cell.

Isolate organelles general meaning and special. Special ones are found in most cells, but are present in significant numbers only in cells that perform a specific function. These include microvilli of intestinal epithelial cells, cilia of the epithelium of the trachea and bronchi, flagella, myofibrils (providing muscle contraction, etc.).

Organelles of general importance include EPS, the Golgi complex, mitochondria, ribosomes, lysosomes, centrioles of the cell center, peroxisomes, microtubules, microfilaments. Plant cells contain plastids and vacuoles. Organelles of general importance can be divided into organelles having a membrane and non-membrane structure.

Organelles having a membrane structure are two-membrane and one-membrane. Two-membrane cells include mitochondria and plastids. To single-membrane - endoplasmic reticulum, Golgi complex, lysosomes, peroxisomes, vacuoles.

Membraneless organelles: ribosomes, cell center, microtubules, microfilaments.

Mitochondria are round or oval shaped organelles. They consist of two membranes: internal and external. The inner membrane has outgrowths - cristae, which divide the mitochondria into compartments. The compartments are filled with a substance - a matrix. The matrix contains DNA, mRNA, tRNA, ribosomes, calcium and magnesium salts. This is where protein biosynthesis takes place. The main function of mitochondria is the synthesis of energy and its accumulation in ATP molecules. New mitochondria are formed in the cell as a result of the division of old ones.