Department of Health and Adaptive Physical Culture

ABSTRACT

On the topic "Blood groups, their biological significance"
By discipline "Physiology"

Executor:

Supervisor:

Introduction……………………………………………………………………….3
Chapter 1. Concept of antigens and antibodies……………………….………….4

Antigens………………………………………………………………4
Antibodies…………………………………………………………………………………4

INTRODUCTION

Blood is a liquid connective fabric filling cardiovascular systemvertebrates, including humans and some invertebrates . Consists of liquid part plasma and formed elements: cells leukocytes, red blood cells, and platelets . Circulates through the system vessels under the influence of the force of rhythmically contracting hearts , and directly with other tissues body not reported due to availabilityhistohematic barriers. On the surface of red blood cells there are specific substances that have antigenic properties. These substances determine blood groups.
The concept of blood groups arose in 1901 thanks to the work of the Austrian immunologist Karl Landsteiner. He established the presence of specific proteins in plasma and in the membrane of erythrocytes. As a result of these studies, three blood groups were identified, and in 1907, the Czech scientist Jan Jansky discovered the fourth group. These groups made up the blood system called AB0
Currently, over 10 blood group systems have been studied: AB0, Rh factor ( Rh), MNSs, Lewis,Kell-Cellano,Duffy,Kidd,Gerbich, Diego, Lutheran, Xg and others. At the same time, not all blood groups have been discovered and studied.
The determination of blood groups is based on the principle of specific (complementary) interaction between antigens and antibodies. Antigens And antibodies– these are substances capable of complementary binding to form complexes (antigen-antibody). Reactions between antigens and antibodies are called serological.
Belonging to a certain blood group is congenital and does not change throughout life. The most important is the division of blood into four groups according to the “AB0” system and into two groups according to the “Rhesus” system. Maintaining blood compatibility in these particular groups is of particular importance for safeblood transfusion.

Chapter 1. CONCEPT OF ANTIGENS AND ANTIBODIES

Antigens

Antibodies

Chapter 2.GENETIC-PHYSIOLOGICAL CHARACTERISTICS OF SOME BLOOD GROUPS

It has been proven that blood groups are 100% determined by genotype. Thus, blood groups can and should be characterized from both a physiological (immunochemical) and genetic point of view.

2.1. Genetic and physiological characteristics of the AB0 system
From the point of view of genetics, the most studied is the AB0 system, which determines I (0), II (A), III (B) and IV (AB) blood groups. On the surface of red blood cells there may be agglutinogens (antigens) A and B, and in the blood plasma there may be agglutinins (antibodies) a and b . Normally, agglutinogens and agglutinins of the same name are not detected together. It should be noted that A- and B-antigens form a numerous series of antigens (A 1, A 2 ... A; B 1, B 2 ... B).
Inheritance of blood groups of the AB0 system. In the AB0 system, the synthesis of agglutinogens and agglutinins is determined by the alleles of the I gene: I 0, I A, I B. Gene I controls both the formation of antigens and the formation of antibodies. In this case, complete dominance of the alleles is observed I A and I B over the allele I 0, but joint dominance (codominance) of alleles I A and I B. The correspondence of genotypes, agglutinogens, agglutinins and blood groups (phenotypes) can be expressed in the form of a table:
Table 2. Correspondence of genotypes to blood groups

Purpose of the lesson: To provide an understanding of human blood groups and the causes of group differences.

Equipment:

• Table “Blood”.
• Test tubes with human blood.
• Natural plasma.
• Plate and reagents for determining blood groups.

Lesson objectives:

Educational

• Acquisition and assimilation of students’ meanings on the topic “Blood groups”.

Educational tasks

• Development of a dialectical-materialistic worldview based on scientific discoveries about immunity and blood group differences, as well as medical genetics.
• Caring for and maintaining your health.
• The pursuit of knowledge.

Developmental

• Education is related to mental development and thinking. During the learning process, the development of the individual’s intellectual qualities should occur - interest, observation, problem solving, the ability to draw conclusions and generalizations.

Nature of cognitive activity:

• Reproductive – listening, remembering, working with a book.
• Productive - search and research - solve a problem, find something, draw up a diagram.
• Creative - solving a particular problem of increased difficulty, coming up with something yourself, creating an original problem, program, etc.

Lesson progress

I. Organizational aspects

II. Repetition of the covered topic

Individual survey:

1. Draw a diagram of the internal environment of the body.
2. Draw a table and write down the leukocyte formula (types of leukocytes).
3. Talk about the first component of the internal environment, blood: what it is, what it consists of.

Frontal survey on the previously studied topic “Immunity”:

What protective barriers do you know about the body against infections? Name them.

a) 1st barrier – skin, mucous membranes (saliva, tears, sweat)

b) 2nd barrier – elements of the internal environment: blood, tissue fluid, lymph.

What blood cells perform a protective function? (leukocytes).

What is the name of the method of protecting the body from living microorganisms and foreign substances that enter the body? (immunity)

Why does organ transplantation cause organ rejection? (also due to immunity - in particular protein incompatibility)

What types of immunity exist?

a) Nonspecific - by phagocytosis (discovered by I.I. Mechnikov)

b) Specific – because the body is able to recognize substances other than its cells and tissues

What are substances that cause an immune reaction called? – antigens(viruses, bacteria, foreign tissue cells)

What about substances that destroy antigens? – antibodies(humoral mechanism)

What types of lymphocytes do you know? (T-lymphocytes, B-lymphocytes)

Their functions?

a) T-lymphocytes - recognize microbial and other antigens.

b) B lymphocytes – secrete antibodies into the blood.

But if, after all, substances - microbes - have penetrated the cell, then the cell itself begins to fight, releasing substances such as... (interferon)

Who and how discovered the immune properties of organisms? – Eduard Diseyner, English doctor (1749-1823)

What did he suggest?

What is a vaccine? (killed or weakened microbes that are introduced into organism in the form vaccinations)

Which scientist subsequently also used this method and created a vaccine against rabies? (Louis Pater, French microbiologist)

What is a healing serum? (serum with prepared antibodies)

Conclusion: Thus, the immune system performs the following functions

• 1 function – the ability to identify any foreign agents that have entered the body and reject them.
• Function 2 is to reject foreign cells that arise in the body itself due to mutations.
• 3rd function – ability to form immune memory, which can exist throughout life and provide defensive reaction on re-introduction of microorganisms.

A disease that destroys the entire immune system? (AIDS)

What infectious diseases do you know and have suffered from?

Infectious (viruses, bacteria) – acute respiratory infections, pneumonia, influenza, bird flu, AIDS, whooping cough, diphtheria, polio, measles, smallpox.

III. Studying a new topic: “Blood groups”

Lesson objectives:

1. Introduce students to the history of blood transfusion.
2. Reveal the significance of blood transfusion as an important achievement of modern medicine.
3. Find out the reasons for group differences in people.

Introduction to the topic:

1) Teacher - question to the class: What functions does blood perform?

Why is it called the “river of life”?

2) history – the use of blood for therapeutic purposes:

1492 – Pope Innocent VIII, blood of three ten-year-old boys.

History - blood transfusion, first experiments:

/successful/ a) 1666 – London anatomist Robert Lower. 1st experience of blood transfusion on animals – dogs.

/successful/ b) 1667 – French. scientist Denis transfused the blood of a lamb to a bleeding patient young man, after twenty bloodlettings, 2 transfusions were given to a specially hired Parisian porter.

In total, Denis performed 6 transfusions, but 2 are over unsuccessful (!) and criminal proceedings were initiated against him. He was acquitted, but blood transfusions were prohibited! (1670) – French. parliament

/person/ In 1819 - English. obstetrician Blandham performed 1 blood transfusion from person to person. In this way he saved the life of a bleeding woman in labor.

Problem task –

Teacher: Thus, from the given examples from the history of blood transfusion, blood transfusion has been tried for a long time, but sometimes it was accompanied success, and sometimes led to death those who received blood transfusions.

Question: How to explain this?

Discovery of blood group:

In 1901, the German scientist Ehrlich and his student Karl Landsteiner discovered three blood groups, and then the Czech scientist J. Jansky discovered another blood group IV. Thus, the entire population of the globe has 4 different blood groups.

Question: What are group differences based on?

Science has helped answer this question. genetics. Not only morphological characteristics can be hereditary - hair color, eye color, structural features, but some can also be inherited biochemical features - proteins found in red blood cells And blood plasma. Kit these proteins every person strictly permanent! These sets are different for different people.

Table of group differences

Agglutination is the process of coagulation (gluing) of red blood cells.

People of the same blood type have a similar protein composition, so their blood is compatible.

According to the table, indicate what blood, what group, where can be infused.

Give the concept:

1 . Universal donor

2. Universal recipient

Rh – concept of the Rh factor:

Recently, many other blood factors have been discovered, of which the so-called Rh (Rh factor) is of greatest practical importance. It was first discovered in the blood of a rhesus monkey. Approximately 85% of people's red blood cells contain a protein - the Rh factor, and 15% of the population do not have it. Its absence does not affect the quality of blood, but it must be taken into account during blood transfusions and during pregnancy. Rh “-” – people should only be transfused into RH “-” blood, because When Rh “+” protein (antigen) enters the blood, antibodies begin to be produced against it. In newborns, if the mother is Rh “-” and the fetus develops Rh “+”, the mother produces antibodies and the child is born with hemolytic disease (orange skin color).

Rh is the Rh factor, discovered by the same Karl Landsteiner together with a researcher Wiener in 1937–1940 For both discoveries, Landsteiner was awarded the Nobel Prize twice.

The importance of knowledge about blood groups:

If the human mind had not penetrated the genetic mystery of the properties of blood and tissues, thousands of people would have died from reactions as a result of blood transfusions and millions of lives would have been lost in hospitals and in war, from the impossibility of blood transfusions.

Knowledge of blood groups has a well-known forensic medical significance:

a) determination of the blood type of the criminal, blood stains at the crime scene and things

b) determination of paternity

c) Rh value during pregnancy (Rh conflict!)

1) because blood is a liquid connective tissue, then group compatibility depends on tissue compatibility

2) histocompatibility depends on the hereditary combination of certain blood proteins

Fastening:

1. Who first discovered group differences?
2. How many blood types does a person have?
3. What are the group differences based on? (certain combinations of proteins, red blood cells and plasma)
4. What other blood indicator should be taken into account during transfusion? (Rh factor)
5. What blood type can be transfused to other people without risk? Why?
6. What blood type can people accept any blood? Why?
7. The importance of knowledge about blood groups.

Homework:

• § 19, page 97
• Answer the questions at the end of the paragraph.
• Find out your group and Rh from your parents.
• Prepare reports on the topic: “Organ transplantation and problems of their compatibility.”

Blood groups

There are 4 blood groups: OI, AII, BIII, ABIV. Group characteristics of human blood are a permanent feature, are inherited, arise in the prenatal period and do not change during life or under the influence of diseases.

It was found that the agglutination reaction occurs when antigens of one blood group (they are called agglutinogens), which are found in red blood cells - erythrocytes, stick together with antibodies of another group (they are called agglutinins) that are found in plasma - the liquid part of the blood. The division of blood according to the AB0 system into four groups is based on the fact that the blood may or may not contain antigens (agglutinogens) A and B, as well as antibodies (agglutinins) α (alpha or anti-A) and β (beta or anti-B) .

First blood group - 0 (I)

Group I - does not contain agglutinogens (antigens), but contains agglutinins (antibodies) α and β. It is designated 0 (I). Since this group does not contain foreign particles (antigens), it can be transfused to all people. A person with this blood type is a universal donor.

It is believed that this is the most ancient blood group or group of “hunters”, which arose between 60,000 and 40,000 BC, during the era of Neanderthals and Cro-Magnons, who only knew how to gather food and hunt. People with the first blood group have leadership qualities.

Second blood group A β (II)

Group II contains agglutinogen (antigen) A and agglutinin β (antibodies to agglutinogen B). Therefore, it can be transfused only to those groups that do not contain antigen B - these are groups I and II.

This group appeared later than the first, between 25,000 and 15,000 BC, when man began to master agriculture. There are especially many people with the second blood group in Europe. It is believed that people with this blood type are also prone to leadership, but are more flexible in communicating with others than people with the first blood group.

Third blood group Bα (III)

Group III contains agglutinogen (antigen) B and agglutinin α (antibodies to agglutinogen A). Therefore, it can be transfused only to those groups that do not contain antigen A - these are groups I and III.

The third group appeared around 15,000 BC, when humans began to populate the colder regions to the north. This blood group first appeared in the Mongoloid race. Over time, the group's carriers began to move to the European continent. And today there are a lot of people with such blood in Asia and Eastern Europe. People with this blood type are usually patient and very efficient.

Fourth blood group AB0 (IV)

Blood group IV contains agglutinogens (antigens) A and B, but contains agglutinins (antibodies). Therefore, it can only be transfused to those who have the same, fourth blood group. But, since there are no antibodies in the blood of such people that can stick together with antibodies introduced from outside, they can be transfused with blood of any group. People with blood group IV are universal recipients.

Type 4 is the newest of the four human blood types. It appeared less than 1000 years ago as a result of the mixing of Indo-Europeans, carriers of group I, and Mongoloids, carriers of group III. It is rare.

Blood type There are no OI agglutinogens, both agglutinins are present, the serological formula of this group is OI; blood of group AN contains agglutinogen A and agglutinin beta, serological formula - AII blood of group VSh contains agglutinogen B and agglutinin alpha, serological formula - BIII; blood of the ABIV group contains agglutinogens A and B, there are no agglutinins, the serological formula is ABIV.

Under agglutination we mean the sticking of red blood cells and their destruction. “Agglutination (late Latin word aglutinatio - gluing) - gluing and precipitation of corpuscular particles - bacteria, erythrocytes, platelets, tissue cells, corpuscular chemically active particles with antigens or antibodies adsorbed on them, suspended in an electrolyte environment"

Blood group (phenotype) is inherited according to the laws of genetics and is determined by a set of genes (genotype) obtained with the maternal and paternal chromosome. A person can only have those blood antigens that his parents have. Inheritance of blood groups according to the ABO system is determined by three genes - A, B and O. Each chromosome can have only one gene, so the child receives from his parents only two genes (one from the mother, the other from the father), which cause the appearance of two genes in red blood cells ABO system antigens. In Fig. Figure 2 shows a diagram of the inheritance of blood groups according to the ABO system.

Blood antigens appear in the 2-3rd month of intrauterine life and are well defined by the birth of the child. Natural antibodies are detected from the 3rd month after birth and reach their maximum titer by 5-10 years.

Blood group inheritance scheme according to the ABO system

It may seem strange that blood type can determine how well the body absorbs certain foods, however, medicine confirms the fact that there are diseases that are most often found in people of a certain blood type.

The method of nutrition based on blood groups was developed by the American doctor Peter D'Adamo. According to his theory, the digestibility of food and the effectiveness of its use by the body is directly related to the genetic characteristics of a person, his blood type. For the normal functioning of the immune and digestive systems, a person needs to consume foods that correspond to his blood group. In other words, those foods that his ancestors ate in ancient times. Excluding substances incompatible with blood from the diet reduces the body’s sludge and improves the functioning of internal organs.

You don't have to be a vampire to understand the peculiarities of human blood. It is enough just to listen more or less carefully to the teacher during school biology lessons.

Well, if you still didn’t listen to him, and now you urgently need this knowledge (for example, to write a thesis in biology about blood groups), we will be happy to help you and tell you about blood groups in the most accessible and understandable way. Let's go!

A little history

Back in the 8th century BC, the works of the poet Homer described the use of blood for medicinal purposes. However, in those distant times (both in the 6th century and in the Middle Ages), people could only think of using this component as a healing drink. It was believed that drinking blood promotes rejuvenation.

The circulatory system was described in more or less detail only in 1628. Scientist William Harvey determined the basic principles and laws of blood circulation in the body. It was thanks to his work that subsequent scientists were able to develop a blood transfusion technique.

Note!

The first blood transfusion took place in 1667. It was successfully carried out by Jean-Baptiste Denis, a French scientist and personal physician to King Louis XIV. On his orders, sheep blood, collected by using leeches, was transfused into a 15-year-old boy. And the strangest thing is that he survived!

The use of human blood for the same purposes was made only in the 18th century. To save his patient, obstetrician James Blundell transfused her with her husband's blood.

Despite the active practice of blood transfusions since then, the mortality rate of patients was still extremely high. And all because such a concept as blood groups was discovered only in 1901, and in 1940 the concept of the Rh factor appeared.

Our days

Today in medicine, human blood is classified into two main groups:

1. AB0 system

This system was proposed by Karl Landsteiner in 1900. He discovered protein substances in red blood cells, which he called agglutinogens. Karl divided these adhesives into 2 types - A and B.

Agglutinins were also found in blood plasma. They are also divided into 2 types - α and β.

The process of agglutination occurs when agglutinogens and agglutinins meet. In this case, agglutinin α connects the erythrocyte to agglutinogen A. Accordingly, agglutinin β connects erythrocytes to agglutinogen B.

Agglutination is the gluing and precipitation of red blood cells carrying antigens under the influence of specific substances in the blood plasma - agglutinins.

It is impossible to find the same agglutinogens and agglutinins (A with α and B with β) in the blood at the same time. This is only possible if the transfusion is carried out incorrectly. And if this happens, then the red blood cells begin to stick together. The glued lumps clog the capillaries and become deadly to human life. Moreover, immediately after the red blood cells stick together, they begin to collapse. As a result of decay, toxic products are released that poison the entire body, thereby causing various kinds of complications, including death.

This reaction (agglutination) is used precisely to identify the blood type. This process involves donor(a person giving his blood) and recipient(the person receiving this blood during the transfusion process).

Important!

Neither race nor nationality of people in any way influences a particular blood type. It becomes clear at birth and remains unchanged throughout life.

Moreover, there are clear rules about which group can be transfused to whom. Here's the diagram:

True, if we are talking about transfusion of large volumes of blood, then it is better to choose the same group for the donor as for the recipient.

1. Rh system

There have been cases when, even if all optimal conditions were met, serious complications occurred during transfusion of even the same blood from donor to recipient. And the thing was Rhesus conflict.

85% of people have a protein in their blood called the Rh factor. This name was given to him thanks to his first owner - a rhesus monkey. Accordingly, the remaining 15% do not have this Rh factor.

Blood that contains the Rh factor is designated Rh (+) and is called positive. Blood that does not have the Rh factor is called negative, and is designated Rh (-).

When transfusing, it is necessary to take into account the presence or absence of this moment in the donor and recipient, since there are no antibodies in the blood plasma for this component of the blood. True, if you transfuse the blood of a Rh-positive person to a Rh-negative person, such antibodies can form. And this is also important to know!

In general, you see how important it is to know blood groups, mathematical laws in biology and inheritance of blood type, as well as other nuances - this can save lives. And if you intuitively understand all this, but are not able to complete, say, a test, essay or coursework on blood groups (biology), you can watch the video lesson below or ask for help from to our authors– qualified biologists with experience.

And here is the promised short video lesson on blood groups in biology:
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The accepted international classification designates each blood group by the presence or absence of two serum agglutinins, which are called alpha (a) and beta (b) and two erythrocyte agglutinogens, called A and B. The first blood group is determined by the fact that there are no agglutinogens in its erythrocytes , and serum contains both agglutinins - alpha and beta. Thus, the complete blood formula of group 1 is: I (0ab). In group II blood, red blood cells have only one agglutinogen - A, and serum contains one agglutinin - beta. Thus, the complete blood formula of group II is: II (Ab). Blood group III is characterized by the fact that red blood cells have only one agglutinogen - B, and its serum contains only one agglutinin - alpha. Thus, the complete blood formula of group III is III (Ba). Blood group IV is distinguished by the fact that its red blood cells have both agglutinogens - A and B, and its serum does not contain agglutinins at all. Thus, the complete blood formula of group IV is (ABo). Currently, it is customary to designate blood groups by number and by the content of erythrocyte agglutinogens: I(0); II(A); III(B); IV(AB). The content of agglutins and agglutinogens in human blood is constant and does not change throughout life. The titer of agglutinins may fluctuate due to the state of the body and diseases. Erythrocyte agglutinogens appear in the 3rd month of intrauterine life of the fetus, and serum agglutinins appear during the first year of life. The serum agglutinin titer of children is low, which explains the fact that children tolerate blood transfusions (both single-group and universal) with less reaction. Selective adsorption has established that agglutinogen A has two varieties: A1 and A2, with A1 occurring in 95% of cases, and A2 in 5% of cases. Consequently, we can talk about six blood groups, but in practical work on blood transfusion, people are divided into four groups. The distribution of blood groups among the population of different countries has some differences, but on average it is believed that people of group I (0) are 41%, II (A) - 38%, III (B) - 18% and IV (AB) - 3% . Blood type is determined using standard anti-A and anti-B sera or zoliclones. Blood transfusion is mandatory after: Determining the patient's blood type. Determining the donor's blood group. Tests for individual compatibility. Biological compatibility tests. Rh factor. In 85% of people, red blood cells have a special antigenic substance called the Rh factor. These people are considered Rh positive, and the remaining 15%, who do not have the Rh factor in their blood, are Rh negative. Transfusion of Rh-positive blood into Rh-negative patients results in the development of Rh antibodies. With repeated transfusions, they experience a severe post-transfusion reaction that can lead to death. To prevent this complication, a blood test to check the Rh factor is mandatory. For Rh-negative patients, as well as in all doubtful cases, only Rh-negative blood can be transfused. The effect of transfused blood on the patient. Currently, the substitutive, stimulating, hemostatic (hemostatic), neutralizing (detoxification), immunobiological and nutritional effects of transfused blood are distinguished. Blood transfusion is absolutely indicated in cases where it cannot be replaced by other methods of treatment, and refusal of it will sharply worsen the condition (or lead to the death of the patient.