If you place the human erythrocytes into a saline solution of the concentration of which. Erythrocytes in a hypertonic solution of red blood cells in a solution of cook salt

Date: 19.07.2019

According to the program I.N. Ponomareva.

Textbook: Biology man. A.G. Dragomilov, R.D. Mash.

Type of lesson:

1. According to the main didactic objective of the study of a new material;

2. According to the method and stages of the educational process-combined.

Lesson Methods:

1. By the nature of cognitive activity: explanatory-illustrated, problem-search.

2. In view of the source of knowledge: verbally visual.

3. in form joint activity Teachers and Pupils: Story, Conversation

Purpose: deepen the importance of the inner environment of the body and about homeostasis; clarify the blood coagulation mechanism; Continue the development of microscopic skills.

Didactic tasks:

1) The composition of the inner environment of the body

2) blood composition and its function

3) blood coagulation mechanism

1) call the components of the internal environment of the human body

2) Determine under a microscope, blood cell drawings: red blood cells, leukocytes, platelets

3) indicate blood cell functions

4) characterize composite components of blood plasma

5) establish the relationship between the structure and functions of blood cells

6) clarify the value of blood test as a means of diagnosing diseases. Justify your opinion.

Developing tasks:

1) The ability to perform tasks, managing a guidance instructional briefing.

2) Remove the necessary information from sources of knowledge.

3) the ability to draw conclusions after viewing the slides on the topic "Blood"

4) skill filling schemes

5) analyze and evaluate information

6) develop creative abilities in students

Educational challenges:

1) Patriotism on life activity I.I. Mechnikov

2) Formation of a healthy lifestyle: a person must follow the composition of his blood, eating food, rich protein and iron, avoid blood loss and dehydration.

3) Create conditions for the formation of self-assessment of the individual.

Requirement for training learning:

Find out:

blood cells under a microscope, drawings

Describe:

blood cell functions;
blood coagulation mechanism;
function of composite components of blood plasma;
signs of Malokrovia, Hemophilia

Compare:

young and mature man erythrocyte;
erythrocytes of man and frogs;
the number of erythrocytes in newborns and adults.

Blood plasma, red blood cells, leukocytes, platelets, homeostasis, phagocytes, fibrinogens, blood coagulation, thromboplastin, neutrophils, eosinophils, basophiles, monocytes, lymphocytes, isotonic, hypertonic, hypotonic solutions, saline.

Equipment:

1) Table "Blood"

2) Electronic Disc "Cyril and Methodius", theme "Blood"

3) solid human blood (sized and centrifugated and simple).

4) Microscopes

5) Micropreparations: human blood and frogs.

6) Raw potatoes in distilled water and salty

7) saline

8) 2 red mantles, white robe, balloons

9) Portraits I.I. Mechnikova and A. Levenguka

10) Red and white plasticine

11) Presentations of students.

Stages lesson

1. Actualization of reference knowledge.

Claude Bernard: "I first began to insist on the idea that there are actual 2 environments for animals: one environment is an external, in which the body is placed, and the other environment is the inner, in which the elements of tissues live.

Fill the table.

"The components of the inner medium and their location in the body." See Appendix No. 1.

2. Increased new material

Mephistopheles, offering the Fatus to sign the Union with the "unclean force," said: "Blood, you need to know, very special juice." In these words, the mystical belief in the blood is reflected in something mysterious.

Behind blood was recognized by mighty and exceptional strength: the blood bonded the sacred oaths; The priests made their wooden idols "cry blood"; Ancient Greeks brought blood sacrificing to their gods.

Some philosophers of ancient Greece considered blood with a carrier of the soul. Ancient Greek doctor Hippocrates appointed heartless blood healthy people. He thought that in the blood of healthy people - a healthy soul.

Indeed, blood is the most amazing tissue of our body. Blood mobility is the most important conditions for the life of the body. It is not necessary to imagine a state without transport links, it is impossible to understand the existence of a person or an animal without the flow of blood along the vessels, when oxygen, water, proteins and other substances are separated into all organs and tissues. With the development of science, the human mind penetrates deeper into many secrets of blood.

So, total amount The blood in the human body is 7% of its weight, it is about 5-6 liters in an adult and about 3 liters in adolescents.

What functions does blood perform?

Pupil: Demonstrates the support abstract and explains the blood function. See Appendix No. 2.

At this time, the teacher makes additions by the electronic disk "Blood".

Teacher: What does blood consist of? Demonstrates a centrifuged blood, where 2 are visible to the layer clearly different from each other.

The top layer is a slightly yellowish translucent fluid - blood plasma and the lower layer - the precipitate of dark-red color, which is formed by uniform elements - blood cells: leukocytes, platelets and red blood cells.

The originality of blood is that it is a connecting tissue, whose cells are weighted in a liquid intermediate substance - plasma. In addition, cell reproduction occurs in it. The execution of old, dying blood cells is carried out by the bloodstream occurring in the red bone marrow, which fills the space between the bone crossbars of the spongy substance of all bones. For example, the destruction of the constituted and damaged red blood cells occurs in the liver and spleen. The total volume of it in an adult is 1500 cm 3.

The blood plasma includes many simple and complex substances. 90% of the plasma is water, and only 10% of it falls on the dry residue. But how diverse his composition! Here and the most complex proteins (albumin, globulines and fibrinogen), fats and carbohydrates, metals and halides are all elements of the Mendeleev table, salt, rhymes and acids, various gases, vitamins, enzymes, hormones, etc.

Each of these substances has a certain important.

A student with the Crown "Proteins" - "Building Material" of our body. They are involved in blood coagulation processes, maintain the constancy of the blood reaction (weakly alkaline), forms immunoglobulins, antibodies involved in protective reactions organism. High molecular weight proteins that do not penetrate through the walls of blood capillaries, hold in plasma a certain amount of water, which is important for balanced fluid distribution between blood and tissues. The presence of plasma proteins provides blood viscosity, the constancy of its vessel pressure, prevents erythrocyte settlement.

Pupil with crown "Fats and carbohydrates" - energy sources. Salts, lumps and acids support the constancy of the inner medium, the changes of which is dangerous for life. Enzymes, vitamins and hormones provide the right metabolism in the body, its growth, development and mutual influence of organs and systems.

Teacher: The total concentration of mineral salts, proteins, glucose, urea and other substances dissolved in plasma creates osmotic pressure.

Osmosis phenomenon occurs everywhere, where there are 2 solutions of various concentrations separated by a semi-permeable membrane through which the solvent (water) is easily passed, but the solute molecules do not pass. Under these conditions, the solvent moves towards the solution with a large concentration of the dissolved substance.

Due to somatic pressure, the fluid penetration occurs through the cell shells, which ensures the exchange of water between blood and tissues. The constancy of osmotic blood pressure is essential for the vital activity of the cell cells. Membranes of many cells, including blood cells, are also semi-permeable. Therefore, when placing erythrocytes to solutions with different concentrations of salts, and, consequently, serious changes occur with different osmotic pressure.

A saline, having the same osmotic pressure as blood plasma is called isotonic solution. For a person, a 0.9% salt salt isotonic.

Saline osmotic pressure which is higher than the osmotic pressure of blood plasma, are called hypertonic; If the osmotic pressure is lower than in the blood plasma, then such a solution is called hypotonic.

Hypertensive solution (10% NaCl) - used in the treatment of purulent wounds. If you put a bandage with a hypertonic solution on the wound, then the fluid from the wound will go out, on the dressing, since the concentration of salts in it is higher than inside the wound. At the same time, the fluid will be enthusized with the pussy, microbes, dead tissue particles, and as a result of the wound, clean and heal.

Since the solvent is always moving towards a solution with a higher osmotic pressure, then when the erythrocytes are immersed in a hypotonic solution, water, according to the law of osmosis, is intensively starting to penetrate inside the cells. Erythrocytes swell, their shells are broken, and the contents enters the solution.

For normal operation of the body, it is not only a quantitative content of salts in the blood plasma. Extremely important I. qualitative composition These salts. The heart, for example, will stop, if the liquid flowing through it is completely eliminating calcium salts, the same will occur during the excess of potassium salts. Solutions that, according to its high-quality composition and salt concentration, correspond to the composition of the plasma, are called physiological solutions. They are different for different animals. Such fluids are used to maintain the vital activity of the organs from the body, as well as blood substitutes for blood loss.

Task: Prove that violation of the constancy of the salt composition of blood plasma by diluting it with distilled water leads to the death of red blood cells.

Experience can be delivered demonstration. In 2 test tubes poured the same amount of blood. Distilled water is adhered to one sample, to the other - saline (0.9% NaCl solution). Students should notice that the test tube in which the physiological solution is adhered to the blood, remained opaque. Consequently, the uniform elements are preserved, remained in suspension. In the tube, where distilled water was adhered to the blood, the liquid became transparent. The contents of the test tube are no longer a suspension, became a solution. So, uniform elements here, first of all, red blood cells were destroyed, and hemoglobin moved into the solution.

Recording experience can be issued as a table. See Appendix No. 3.

The significance of the constancy of the salt composition of blood plasma.

The causes of the destruction of erythrocytes at blood pressure can be explained so. Erythrocytes have a semi-permeable membrane, it skips the water molecules, but the salts and other substances are poorly missed. In red blood cells and blood plasma, the percentage of water is approximately equal, therefore, for a certain unit of time in the erythrocyte of plasma, approximately the same amount of water molecules are falling out of the plasma erythrocyte. When blood diluted with water, water molecules outside the erythrocytes becomes greater than inside. As a result, the number of water molecules penetrating the red blood cells increases. He swells, the membrane is stretched, the cell loses hemoglobin. It goes into a plasma. The destruction of blood erythrocytes in the human body can occur under the influence of various substances, for example, poison of viper. Once in a plasma, hemoglobin is rapidly lost: it easily passes through the walls of the vessels, excreted from the body by the kidneys, destroys the tissues of the liver.

Disruption of plasma composition, as well as any other violation of the constancy of the internal medium, is possible only in relatively small limits. Due to the nervous and humoral self-regulation, the deviation from the norm causes changes in the body that restores the norm. Significant changes in the constancy of the composition of the inner medium lead to the disease, and sometimes they are the cause of death.

Student in the Red Mantle and Crown "Erythrocyte" with balloons in hand:

All that is contained in the blood, everything that she carries on the vessels is intended for the cells of our body. They are selected from it everything you need and use on your own needs. Only an oxygen-containing substance should be untouched. After all, if it is to settle in the tissues, collapse there and used for the needs of the body, it will be difficult to transport oxygen.

At first, nature went on the creation of very large molecules, the molecular weight of which is two, about that and ten million times the volume of hydrogen, the easiest substance itself. Such proteins are not capable of passing through the cell membranes, the "shower" even in rather large pores; That is why they remained in debt in the blood and could be repeatedly used. For higher animals, a more original solution was found. The nature provided them with hemoglobin, whose molecular weight is only 16 thousand times more than at the hydrogen atom, but that hemoglobin does not get surrounding tissues, placed it, as in the containers, inside the special, circulating cells with blood - red blood cells.

Erythrocytes of most animals are round, although sometimes their form is changing for some reason, becomes oval. Among the mammals such as freaks are camels and lamas. Why in the design of the erythrocyte of these animals it was necessary to introduce such significant changes as long as it is not known.

At first, the red blood cells were big, bulky. Prota, relict cave amphibians, their diameter 35-58 microns. In most amphibians, they are significantly less, but the volume reaches 1100 cubic microns. It turned out uncomfortable. After all, the more the cage, the relatively less of its surface, in both sides of which the oxygen should pass. A unit of surface accounts for too much hemoglobin, which prevents its full use. Making sure that nature went on the way of reducing the size of red blood cells to 150 cubic microns for birds and up to 70 for mammals. In humans, their diameter is 8 microns, and the volume of 8 cubic microns.

Erythrocytes of many mammals are even smaller, the goats are barely reach 4, and 2.5 micron cabaggs. Why is the goats such small red blood cells, it is not difficult to understand. The ancestors of home goats were mountainous animals and lived in a strongly discharged atmosphere. No wonder they are huge the number of erythrocytes, 14.5 million in each cubic millimeter of blood, whereas in such animals like amphibians, the intensity of the metabolism of which is small, only 40-170 thousand erythrocytes.

In pursuit of reducing the volume of red blood cells of vertebrate animals turned into flat discs. So the path to diffuse-diffusing oxygen molecules diffused as much as possible. In a person, in addition, there is a pressure in the center of the disk on both sides, which made it possible to reduce the amount of cells even more by increasing its size.

Transport hemoglobin in a special container inside the erythrocyte is very convenient, but good without a thinness does not happen. Erythrocyte - live cell. And himself consumes a mass of oxygen for his breathing. Nature does not tolerate waste. She had a lot to break his head to come up with how to reduce unnecessary costs.

The most important part of any cell is the kernel. If it is quietly removed, and such ultramicroscopic operations are able to do, then the nuclear cell, although it does not die, still becomes unwasteless, stops its basic functions, sharply reduces the metabolism. This was decided to use nature, she deprived adult erythrocytes of mammals their nuclei. The main function of the erythrocytes was the hemoglobin containers - the function is passive, and it could not suffer, and the reduction of metabolism was only on hand, since the oxygen consumption is strongly reduced.

Teacher: Red plasticine blind erythrocyte.

Pupil in a white bathrobe and leukocyte crown:

Blood not only vehicle. It performs other important functions. Moving along the body vessels, the blood in the lungs and the intestines is almost directly in contact with the external environment. And light, and especially the intestines, undoubtedly, dirty places of the body. It is not surprising that here in blood is very easy to penetrate microbes. And why not penetrate them? Blood is a wonderful nutrient medium, while rich in oxygen. If you do not put immediately at the entrance, vigilant and inexorable guards, the body's life would be an expensive death.

Guardians were easily found. At the dawn of the emergence of life, all the cells of the body were able to capture and digest particles of organic substances. Almost at the same time, organisms acquired moving cells, very reminiscent of modern amoeb. They did not sit back, waiting for the current of the fluid to bring them something delicious, and lived in the permanent search of the scourge bread. These wandering hunters cells, from the very beginning, incorporated into the struggle with the microbes that hit the body were called leukocytes.

Leukocytes are the largest cells of human blood. Their size ranges from 8 to 20 microns. These dressed in white bathrobes of the sanitary equipment of our body still for a long time Take part in digestive processes. They perform this feature even in modern amphibians. It is not surprising that the lower animals have a lot of them. In fish in 1 cubic millimeter there are up to 80 thousand, ten times more than healthy man.

To successfully combat pathogenic microbes, you need a lot of leukocytes. The body produces them in huge quantities. Scientist failed to find out the duration of their lives. Yes, it is unlikely that it can be accurately installed. After all, leukocytes are soldiers and, apparently, never live to old age, but die in the war, in the fights for our health. Probably, therefore, various animals and in various conditions experienced very birds were obtained - from 23 minutes to 15 days. More precisely, it was possible to establish only life for lymphocytes - one of the varieties of tiny sanitation. It is equal to 10-12 hours, that is, a day, the body is completely at least twice the composition of lymphocytes.

Leukocytes are capable not only to wander inside the bloodstream, but if necessary, it is easily left, deepening in the fabric, towards the microorganisms that fell there. Eat hazardous to the organism of microbes, leukocytes are poisoned by their potent toxins and die, but do not surrender. The wave behind the wave of a solid wall they are on the pathogenic hearth while the resistance of the enemy will not be broken. Each leukocyte can swallow to 20 microorganisms.

The masses are performed by leukocytes on the surface of mucous membranes, where there are always many microorganisms. Only in the human oral cavity - 250 thousand every minute. During the day, 1/80 part of all our leukocytes die here.

Leukocytes are struggling not only with microbes. Another important feature is entrusted to them: destroy all damaged, wear cells. In the body tissues, they constantly disassemble, clearing the place for the construction of new cell cells, and young leukocytes take part in the construction itself, in any case, in the construction of bones, connective tissue and muscles.

Of course, one leukocytes would not be able to defend the body from microbes penetrating into it. In the blood of any animal many different substances that are able to glue, kill and dissolve the microbials in the circulatory system, turn into insoluble substances and neutralize the toxin allocated by them. We get some of these protective substances by inheritance from parents, others learn to develop themselves in the fight against our surrounding enemies.

Teacher: Task: White Plasticine Slip leukocyte.

Pupil in pink mantle and crown "platelet":

No matter how carefully control devices are baroreceptors monitor blood pressure, an accident is always possible. More often the trouble comes from the side. Anyone, even the most insignificant, the wound will destroy hundreds, thousands of vessels, and through these holes now they can jump out the water of the inner ocean.

Creating an individual ocean for each animal, the nature had to occur in the organization of an emergency rescue service in case of the destruction of his shores. At first, this service was not very reliable. Therefore, for the lower beings, nature envisaged the possibility of significant crosses of inland reservoirs. Loss of 30 percent of blood for a person is deadly, the Japanese beetle easily transfers the loss of 50 percent of hemolymph.

If the ship in the sea receives a hole, the command tries to shut down the resulting hole by any utility material. Nature in abundance provided blood with their own pops. These are special spindle-shaped cells - platelets. In size, they are negligible, only 2-4 microns. To shut up such a tiny plot of any significant hole it would be impossible if platelets did not have the ability to stick through the influence of thromboxinase. This enzyme nature richly equipped fabrics surrounding vessels, and other places, most susceptible to injury. With the slightest damage to the tissues of thrombocinase, it is allocated to the outside, enters into contact with blood, and platelets immediately stick together, forming a lump, and blood brings it all new and new building material, because in each cubic millimeter blood is contained 150-400 thousand pieces.

By themselves, the thrombocytees of a large traffic jam can not form. The plug is obtained by falling out the filaments of a special protein - fibrin, which in the form of fibrinogen is constantly present in the blood. In the formed network of fibrin fibers, lumps of flushed platelets, red blood cells, leukocytes are frozen. Pursue a few minutes, and a significant traffic jam is formed. If not very damaged large vessel And blood pressure in it is not so great to push the plug, the leak will be eliminated.

It is hardly profitable that the emergency service duty consumes a lot of energy, and hence the oxygen. Before platelets is the only task - to stick into a minute of danger. The function is passive, does not require significant energy costs, it means that there is no need to consume oxygen until everything in the body is calm and nature with them as well as red blood cells. She deprived them of nuclei and thereby reducing the level of metabolism, lowered the oxygen consumption.

It is quite obvious that a well-established emergency blood service is needed, but it, unfortunately, threatens the body a terrible danger. What if for one reason or another emergency service will start working in time? Such inappropriate actions will lead to a serious accident. Blood in vessels will be killed and borders them. Therefore, blood has a second emergency service - an anti-eating system. It is watching that the blood is not thrombin, whose interaction with fibrinogen leads to the fallout of fibrin yarns. As soon as fibrin appears, the antisvelive system immediately inactivates it.

The second emergency service works very actively. If you introduce a significant dose into the blood of the frog, nothing terrible will happen, it will immediately be neutralized. But if you now take blood from this frog, it turns out that she lost the ability to get out.

The first emergency system works automatically, the second commands the brain. Without his instructions, the system will not work. If the frog first destroy the command post in oblong brain, And then enter thrombin, the blood will instantly come. Emergency service is ready, but no one to submit an alarm.

In addition to the emergency services listed above, the blood also has a major overhaul brigade. When circulatory system It is damaged, not only the rapid formation of blood cloth is important, it is also necessary to the timely removal. While the breakdown vessel shut up the plug, it prevents the wound healing. Repair brigade, restoring the integrity of tissues, it dissolves and dissolves the thrombus.

Numerous watchdogs, control and emergency services securely protect the water of our inner ocean from any surprises, ensuring very high reliability of the movement of its waves and the immutability of their composition.

Teacher: Explanation of blood clotting mechanism.

Cutting blood

Thromboplastin + Ca 2+ + Protromine \u003d thrombin

Thrombin + fibrinogen \u003d fibrin

Thromboplastin - the protein-enzyme is formed during the destruction of platelets.

Ca 2+ - calcium ions present in blood plasma.

Protrombin is not an active protein-enzyme blood plasma.

Thromubin is an active protein enzyme.

Fibrinogen - protein dissolved in blood plasma.

Fibrin - protein fibers insoluble in blood plasma (Trombus)

Throughout the lesson, students fill the table "blood cells" table, and then compared with the reference table. Check each other, put an assessment based on the criteria offered by the teacher. See Appendix No. 4.

Practical part of the lesson.

Teacher: Task number 1

Explore blood under the microscope. Describe red blood cells. Determine whether this blood can belong to a person.

Students for analysis are offered the blood frogs.

During the conversation, students respond to questions:

1. What color has red blood cells?

Answer: Pink cytoplasm, the kernel is painted with nuclear paints in blue colour. Coloring makes it possible not only to better distinguish cellular structures, but also to know their chemical properties.

2. What is the magnitude of red blood cells?

Answer: Quite large, however, in sight of them a bit.

3. Can this blood belong to a person?

Answer: can't. A person belongs to mammals, and the erythrocytes of mammals do not have.

Teacher: Task number 2

Compare human and frog erythrocytes.

When compared, the following is noted. Human erythrocytes is much smaller than erythrocytes frogs. In the field of view of the human erythrocyte microscope, much more than erythrocytes frogs. The absence of the kernel increases the useful tank of the erythrocyte. From these comparisons, it is concluded that the blood of a person is able to bind more oxygen than the blood frogs.

Enter information to the table. See Appendix No. 5.

3. Reflowing material studied:

1. For a medical form "Blood test" see Appendix No. 6, give the characteristic of blood composition:

a) the number of hemoglobin

b) the number of erythrocytes

c) the number of leukocytes

d) Roe and Soe

e) leukocyte formula

e) make a diagnosis of human health

2. Work on options:

1. Warrant: Test work on 5 issues with a choice of one to several questions.

2. Warrant: Select offers in which errors are made and correct these errors.

Option 1

1. Where are red blood cells produced?

a) liver

b) red bone marrow

c) Selezenka

2. Where are red blood cells destroy?

a) liver

b) red bone marrow

c) Selezenka

3. Where are leukocytes formed?

a) liver

b) red bone marrow

c) Selezenka

d) lymphatic nodes

4. What blood shaped blood elements have in the cells of the core?

a) Erythrocytes

b) leukocytes

c) thrombocyte

5. What uniform elements are involved in its collapse?

a) Erythrocytes

b) thrombocyte

c) leukocytes

Option 2.

Find the sentences that mistakes are made and correct them:

1. Increased environment of the body is blood, lymph, fabric liquid.

2. Erythrocytes are red blood cells having a kernel.

3. Leukocytes are involved in the protective reactions of the body, have an amosoid shape and core.

4. Platelets have a kernel.

5. Erythrocytes are destroyed in the red bone marrow.

Tasks for logical thinking:

1. The monitoring of salts of the physiological solution that is sometimes replaced in the experiments of blood, different for cold-blooded (0.65%) and warm-blooded (0.95%). How can you explain such a difference?

2.If pour blood clean water, then blood cells are bursting; If you put them in a concentrated salt solution, it is shrivened. Why this does not happen if a person drinks a lot of water and eat a lot of salt?

3. In the preservation of tissues alive in non-organism, they are not placed in water, but in saline, containing 0.9% of the table salt. Explain why you need to do so?

4. Human crochetes are 3 times less than erythrocytes of the frog, but they are 1mm 3 every 13 times more than a man than the frog. How can you explain this fact?

5. Based microbes that have fallen into some organ can penetrate lymph. If the microbes got from it into the blood, it would lead to a general infection of the body. However, this does not happen. Why?

6.In 1 mm 3 of the blood of the goat is 10 million erythrocytes in size 0.007; In the blood of a frog 1 mm 3 - 400,000 erythrocytes of 0.02. Whose blood is a man, frogs or goats - will be transferred to one of the time more oxygen? Why?

7. In a rapid climbing on the mountain in healthy tourists, "mountain illness" is developing - shortness of breath, heartbeat, dizziness, weakness. These signs with frequent training takes place over time. Suppose what changes are in the blood of a person?

4. Homework

p.13.14. To know the records in the notebook, work number 50,51 p. 35 - Workbook number 1, authors: R.D. Mash and A.G. Dragomilov

Creative task for students:

"Immune memory",

"The work of E. Jenner and L. Pasteur when studying immunity."

"Viral diseases of a person."

Reflection: Guys, raise your hands those who were comfortable and cozy today at the lesson.

What do you think reached the purpose of the lesson?
What did you like most in the lesson?
What would you like to change during the lesson?

In 100 ml of blood plasma, a healthy person contains about 93 g of water. The rest of the plasma consists of organic and inorganic substances. Plasma contains minerals, proteins (including enzymes), carbohydrates, fats, metabolic products, hormones, vitamins.

Minerals Plasma are represented by salts: chlorides, phosphates, carbonate and sodium sulfates, potassium, calcium, magnesium. They can be both in the form of ions and in a non-ionized state.

Osmotic blood plasma pressure

Even minor impaired plasma salt composition may be destructive for many tissues, and above all for blood cells. The total concentration of mineral salts, proteins, glucose, urea and other substances dissolved in plasma creates osmotic pressure.

Osmosis phenomena arise everywhere where there are two solutions of various concentrations separated by a semi-permeable membrane through which the solvent (water) is easily passed, but the molecules of the solute. Under these conditions, the solvent is moving towards the solution with a greater concentration of the dissolved substance. One-sided diffusion of fluid through the semi-permeable partition called osmosis (Fig. 4). The force that causes the solvent movement through a semipermeable membrane, there is osmotic pressure. Via special methods It was possible to establish that the osmotic pressure of the human blood plasma is held at a constant level and is 7.6 atm (1 atm ≈ 10 5 N / m 2).

The osmotic plasma pressure is mainly created by the inorganic salts, since the concentration of sugar, proteins, urea and other organic substances dissolved in plasma is small.

Due to osmotic pressure, fluid penetration occurs through cell shellsThat ensures the exchange of water between blood and tissues.

The constancy of osmotic blood pressure is essential for the vital activity of the cell cells. Membranes of many cells, including blood cells, are also semi-permeable. Therefore, at the room blood Taurus In solutions with different saline concentration, and therefore, with different osmotic pressure in blood cells, serious changes occur due to osmotic forces.

Saline solution having the same osmotic pressure as blood plasma is called isotonic solution. For a person, a 0.9 percent solution of the cooking salt (NaCl) is isotonic, and for a frog - 0.6% solution of the same salt.

Saline solution, the osmotic pressure of which is higher than the osmotic pressure of blood plasma, is called hypertonic; If the osmotic pressure of the solution is lower than in the blood plasma, then such a solution is called hypotonic.

Hypertensive solution (usually this is a 10 percent solution of the cooking salt) is used in the treatment of purulent wounds. If you put a bandage with a hypertonic solution on the wound, then the fluid from the wound will go out, on the dressing, since the concentration of salts in it is higher than inside the wound. At the same time, the fluid will adopt the pus, microbes, dead tissue particles, and as a result of the wound, it will rather be cleaned and will heal.

Since the solvent is always moving towards a solution with a higher osmotic pressure, then when the erythrocytes are immersed in a hypotonic solution, water, according to the laws of osmosis, is intensively starting to penetrate inside the cells. Erythrocytes swell, their shells are broken, and the contents enters the solution. Hemolysis is observed. Blood, the red blood cells of which were hemolysis, becomes transparent, or, as sometimes they say, lacquer.

In the blood of man, hemolysis begins when placing erythrocytes in 0.44-0.48% NaCl solution, and at 0.28-0.3 percent solutions NaCl, almost all red blood cells are destroyed. If the erythrocytes fall into a hypertensive solution, they are wrinkled. Make sure, doing the experiments 4 and 5.

Note. Before spending laboratory works According to the study of blood, it is necessary to master the tack of blood from the finger for analysis.

Initially, the subject and researcher thoroughly wash hands with soap. Then, the subject is wiped with alcohol Unnamed (IV) finger of the left hand. The skin of the pulp of this finger is punctured acute and pre-sterilized by a special needle-aged. When pressed on the finger near the place of the injection, blood appears.

The first drop of blood is cleaned with dry cotton, and the following is used for research. It is necessary to ensure that the drop does not spread along the skin of the finger. Blood is gaining into a glass capillary, immersing its end in the base of the drop and give the capillary horizontal position.

After taking the blood, the finger is again wiped with a wrap, moistened with alcohol, and then lubricate the iodine.

Experience 4.

On one edge of the slide glass, place a drop of an isotonic (0.9 percent) solution NaCl, and on another - a drop of the hypotonic (0.3 percent) solution of NaCl. Pulit the skin of the finger with a needle in conventional method And transfer the glass with a glass of blood into each drop of solution. Mix liquids, cover with covered glasses and consider under the microscope (better with a large magnification). Seen swelling of most erythrocytes in the hypotonic solution. Some of the erythrocytes are destroyed. (Compare with erythrocytes in isotonic solution.)

Experience 5.

Take another glass glass. On one edge, put it a drop of 0.9 percent solution NaCl, and on another - a drop of hypertensive (10 percent) NaCl solution. Put the solutions in each drop at a drop of blood and after stirring, consider them under the microscope. In hypertensive solution, there is a decrease in the dimensions of the erythrocytes, their wrinkling, which is easily detected by the characteristic dipstream edge. In isotonic solution, the edge of the erythrocytes is smooth.

Despite the fact that a different amount of water and mineral salts can flow into the blood, the osmotic blood pressure is maintained at a constant level. This is achieved through kidney activities, sweat ironThrough which water, salts and other metabolic products are removed from the body.

Saline

For normal operation of the body, not only the quantitative content of salts in the blood plasma is important, which provides a certain osmotic pressure. The high-quality composition of these salts is extremely important. The isotonic solution of sodium chloride is not capable of maintaining the operation of the organ was washed. The heart, for example, will stop, if liquids flowing through it completely eliminate calcium salts, the same will occur during the excess of potassium salts.

Solutions that according to their high-quality composition and salts concentration correspond to the composition of the plasma, called physiological solutions. They are different for different animals. Physiology often use ringer and thyroid fluids (Table 1).

In fluids for warm-blooded animals, often, in addition to salts, add more glucose and saturated with a solution with oxygen. Such fluids are used to maintain the vital activity of the organs from the body, as well as blood substitutes during blood loss.

Blood reaction

Blood plasma has not only constant osmotic pressure and a certain qualitative composition of salts, it is maintained in the constancy of the reaction. Practically the medium reaction is determined by the concentration of hydrogen ions. For the response characteristic of the medium use hydrogen indicatordenoted by pH. (Hydrogen indicator - logarithm concentration of hydrogen ions with back sign.) For distilled water, the pH value is 7.07, aclest medium The pH is characterized less than 7.07, and alkaline - more than 7.07. The hydrogen indicator of human blood at a body temperature of 37 ° C is 7.36. Blood active blood reaction. Even minor shifts of the blood pH violate the activities of the body and threaten his life. At the same time, in the process of vital activity as a result of metabolism in tissues, significant quantities are forming acidic products, for example, lactic acid during physical work. With enhanced breathing, when a significant amount of coalic acid is removed from the blood, the blood can be applied. The body usually copes with such deviations of the pH. This feature is carried out buffer substancesBlood. These include hemoglobin, acidic acidic acid salts (hydrocarbonates), phosphoric acid salts (phosphates) and blood proteins.

The constancy of the blood reaction is supported by the activities of the lungs through which carbon dioxide carbon dioxide is removed; Through the kidneys and sweat glands, excess substances having a sour or alkaline reaction are derived.

Blood plasma proteins

From plasma organic substances the greatest value They have proteins. They provide the distribution of water between blood and tissue fluid, maintaining water-salt equilibrium in the body. Proteins are involved in the formation of protective immune bodies, bind and neutralize penetrating into the body toxic substances. Fibrinogen plasma protein is the main coagulation factor. Proteins give blood to the necessary viscosity, which is important for maintaining blood pressure at the constant level.

Article Professional Tutor in Biology T. M. Kulakova

Blood is an intermediate inner environment of the body.This is liquid connective tissue. Blood consists of plasma and uniform elements.

The composition of blood - It is 60% of plasma and 40% of uniform elements.

Plasma blood It consists of water, organic substances (proteins, glucose, leukocytes, vitamins, hormones), mineral salts and decay products.

Forming elements - These are red blood cells and platelets

Plasma blood - This is a liquid part of blood. It contains 90% water and 10% dry matter, mainly proteins and salts.

In the blood there are metabolic products (urea, uric acid), which should be removed from the body. The concentration of plasma salts is equal to the content of salts in blood cells. The blood plasma mainly contains 0.9% NaCl. The constancy of the salt composition ensures the normal structure and function of cells.

In the tests of the EE, there are often questions about solutions: physiological (solution, NaCl salt concentration is 0.9%), hypertensive (NaCl salt concentration above 0.9%) and hypotonic (NaCl salt concentration is below 0.9%).

For example, such a question:

The introduction of large doses of drugs is accompanied by their dilution with saline (0.9% NaCl solution). Explain why.

Recall that if the cell is in contact with the solution, the aqueous potential of which is lower than that of its contents (i.e. hypertensive solution), Water will leave the cell due to osmosis through the membrane. Such cells (for example, erythrocytes) are wrinkled and settled on the bottom of the test tube.

And if placing blood cells into a solution, the aqueous potential of which is higher than the content of the cell, (i.e., the salt concentration in the solution is below 0.9% NaCl), erythrocytes begin to swell, because the water rushes into the cells. In this case, the erythrocytes swell, and their shell is broken.

Word the answer to the question:

1. The concentration of salts in the blood plasma corresponds to the concentration of physiological solution of 0.9% NaCl, which causes the death of blood cells;
2. The introduction of large doses of drugs without dilution will be accompanied by a change in the saline of blood and cause cell death.

We remember that when writing a response to the question, other formulations of the answer, not distorting its meaning.

For erudition: In the destruction of the erythrocyte shell, hemoglobin enters the blood plasma, which is painted in the red color and becomes transparent. Such blood is called lacquer blood.

Plasma mineral substances are represented by salts: chlorides, phosphates, carbonates and sodium sulfates, potassium, calcium, magnesium. They can be both in the form of ions and in a non-ionized state.

Osmotic blood plasma pressure

Osmosis phenomena arise everywhere where there are two solutions of various concentrations separated by a semi-permeable membrane through which the solvent (water) is easily passed, but the molecules of the solute. Under these conditions, the solvent is moving towards the solution with a greater concentration of the dissolved substance. The unilateral diffusion of fluid through the semi-permeable partition is called osmosis (Fig. 4). The force that causes the solvent movement through a semipermeable membrane, there is osmotic pressure. With the help of special methods, it was possible to establish that the osmotic pressure of the human blood plasma is held at a constant level and is 7.6 atm (1 atm ≈ 105n / m2).

Fig. 4. Osmotic pressure: 1 - pure solvent; 2 - saline; 3 - semi-permeable membrane, separating the vessel into two parts; The length of the arrows shows the speed of water through the membrane; A - osmosis, which began after filling with the liquid of both parts of the vessel; B - Establishment of equilibrium; H-pressure balancing osmosis

The osmotic plasma pressure is mainly created by the inorganic salts, since the concentration of sugar, proteins, urea and other organic substances dissolved in plasma is small.

Due to osmotic pressure, fluid penetration through the cell membranes, which ensures the exchange of water between blood and tissues.

The constancy of osmotic blood pressure is essential for the vital activity of the cell cells. Membranes of many cells, including blood cells, are also semi-permeable. Therefore, when placing a blood cell in solutions with different salts concentration, and, consequently, with different osmotic pressure in blood cells due to the osmotic forces, serious changes occur.

A saline, having the same osmotic pressure as blood plasma is called isotonic solution. For a person, a 0.9 percent solution of the cooking salt (NaCl) is isotonic, and for a frog - 0.6% solution of the same salt.

Saline solution, the osmotic pressure of which is higher than the osmotic pressure of blood plasma, is called hypertonic; If the osmotic pressure of the solution is lower than in the blood plasma, then such a solution is called hypotonic.

Since the solvent is always moving towards a solution with a higher osmotic pressure, then when the erythrocytes are immersed in a hypotonic solution, water, according to the laws of osmosis, is intensively starting to penetrate inside the cells. Erythrocytes swell, their shells are broken, and the contents enters the solution. Hemolysis is observed. Blood, the red blood cells of which were hemolysis, becomes transparent, or, as sometimes they say, lacquer.

Note. Before carrying out laboratory work on the study of blood, it is necessary to master the technique of taking blood from the finger of blood for analysis.

After taking the blood, the finger is again wiped with a wrap, moistened with alcohol, and then lubricate the iodine.

Experience 4.

On one edge of the slide glass, place a drop of an isotonic (0.9 percent) solution NaCl, and on another - a drop of the hypotonic (0.3 percent) solution of NaCl. Punch the skin of the finger with a needle in the usual way and glass sticks move the blood drop into each drop of solution. Mix liquids, cover with covered glasses and consider under the microscope (better with a large magnification). Seen swelling of most erythrocytes in the hypotonic solution. Some of the erythrocytes are destroyed. (Compare with erythrocytes in isotonic solution.)

Experience 5.

Despite the fact that a different amount of water and mineral salts can flow into the blood, the osmotic blood pressure is maintained at a constant level. This is achieved thanks to the activities of the kidneys, sweat glands, through which water, salts and other metabolic products are removed from the body.

Saline

Solutions that, according to its high-quality composition and salt concentration, correspond to the composition of the plasma, are called physiological solutions. They are different for different animals. Physiology often use ringer and thyroid fluids (Table 1).

Table 1. The composition of Ringer's liquids and thyroid (in 100 ml of water)

Blood reaction

Blood plasma has not only constant osmotic pressure and a certain qualitative composition of salts, it is maintained in the constancy of the reaction. Practically the medium reaction is determined by the concentration of hydrogen ions. To characterize the reaction of the medium, use the hydrogen indicator denoted by the pH. (Hydrogen indicator - the logarithm of the concentration of hydrogen ions with a reverse sign.) For distilled water, the pH value is 7.07, the acidic medium is characterized by a pH less than 7.07, and alkaline - more than 7.07. The hydrogen indicator of human blood at a body temperature of 37 ° C is 7.36. Blood active blood reaction. Even minor shifts of the blood pH violate the activities of the body and threaten his life. At the same time, in the process of life, as a result of metabolism in tissues, there are a significant amounts of acidic products, such as lactic acid during physical work. With enhanced breathing, when a significant amount of coalic acid is removed from the blood, the blood can be applied. The body usually copes with such deviations of the pH. This function is carried out by buffer substances in the blood. These include hemoglobin, acidic acidic acid salts (hydrocarbonates), phosphoric acid salts (phosphates) and blood proteins.

Blood plasma proteins

Of the organic plasma substances, proteins have the greatest value. They provide the distribution of water between blood and tissue fluid, maintaining water-salt equilibrium in the body. Proteins participate in the formation of protective immune bodies, bind and neutralizing poisonous substances penetrating into the body. Fibrinogen plasma protein is the main coagulation factor. Proteins give blood to the necessary viscosity, which is important for maintaining blood pressure at the constant level.

sohmet.ru.

Practical work number 3 of human erythrocytes in isotonic, hypotonic and hypertensive solutions

It is necessary to take three numbered slide glass. Each glass is a drop of blood, then to a drop on the first glass add a drop of a physiological solution, on the second distilled water on the third - 20% solution. All drops cover with coating glasses. To put to stand up to drugs 10 - 15 minutes, then consider with a large increase in the microscope. In a physiological solution, red blood cells have an ordinary oval form. In the hypotonic environment, the red blood cells swell and then burst. This phenomenon is called hemolysis. In the hypertensive environment, red blood cells begin to shrink, wrinkle, losing water.

Draw red blood cells in isotonic, hypertensive and hypotonic solutions.

Performance test tasks.

Samples of test tasks and situational tasks

chemical compounds that are part of the plasma membrane and, having hydrophobicity, serve as the main barrier to penetrate the water and hydrophilic compounds.

polysaccharides

If the human erythrocytes is placed in a 0.5% NaCl solution, then water molecules

will move mainly into the cage

will move mainly from the cell

night will not move.

they will be equal to move in both directions: into the cell and from the cell.

In medicine, gauze bandages moistened with NaCl solution of a certain concentration are used to purify wounds from pm. For this purpose, a solution is used

isotonic

hypertensive

hypotonic

neutral

type of transport of substances through outdoor plasma membrane Cells that requires ATP energy

pinocytosis

diffusion through the canal

light diffusion

simple diffusion

Situational problem

In medicine, gauze bandages moistened with NaCl solution of a certain concentration are used to purify wounds from pm. What naCl solution uses for this purpose and why?

Practical lesson number 3

The structure of eukaryotic cells. Cytoplasm and its components

The eukaryotic type of cell organization with its high ordering of life processes both in single-cell cells and multicellular organisms is due to the cell compartmentization of the cell itself, i.e. It is divided into structures (components - core, plasmolm and cytoplasm, with organides and inclusions for it), differing in the details of the structure, chemical composition and the separation of functions between them. However, at the same time the interaction of various structures with each other occurs.

Thus, the cell is characterized by integrity and discreteness, as one of the properties of living matter, in addition, has properties of specialization and integration in a multicellular organism.

The cell is a structural and functional unit of all living on our planet. Knowledge of the structure and functioning of cells is necessary for the study of anatomy, histology, physiology, microbiology and other disciplines.

continue the formation of community concepts about the unity of all living on earth and the specific features of representatives of various kingdoms manifested in the cellular level;

explore the features of the organization of eukaryotic cells;

explore the structure and function of cytoplasm organoids;

to be able to find the main components of the cell under a light microscope.

For the formation of professional competencies, the student should be able to:

distinguish between eukaryotic cells and give them morphophysiological characteristics;

distinguish prokaryotic cells from eukaryotic; animal cells from plant cells;

find the main components of the cell (core, cytoplasm, shell) under the light microscope and on the electronogram;

differentiate various organides and inclusions on the cells.

For the formation of professional competencies, the student should know:

features of the organization of eukaryotic cells;

the structure and function of cytoplasm organoids.

studfiles.net

Osmotic blood pressure

Osmotic pressure is called the force that causes the solvent (for blood it is water) through a semi-permeable membrane from a solution with a smaller concentration into a more concentrated solution. Osmotic pressure determines the transport of water from the extracellular medium of the body into the cells and vice versa. It is due to soluble in the liquid part of the blood osmotically active substancesTo which ions, proteins, glucose, urea, etc. include.

Osmotic pressure is determined by the cryoscopic method by determining the freezing point of blood. It is expressed in the atmospheres (atm.) And millimeters of a mercury pillar (mm Hg. Art.). It is calculated that the osmotic pressure is 7.6 atm. or 7.6 x 760 \u003d mm RT. Art.

To characterize the plasma as the inner environment of the body, the total concentration of all ions and molecules contained in it, or its osmotic concentration. The physiological significance of the constancy of the osmotic concentration of the inner medium is to maintain the integrity of the cell membrane and ensure the transport of water and dissolved substances.

Osmotic concentration B. modern biology It is measured in osmola (OSM) or milliosmoles (MOS) - a thousandth share of osmol.

Osmol is the concentration of one praying of non-electrolyte (for example, glucose, urea, etc.) dissolved in a liter of water.

The osmotic concentration of non-electrolyte is less than the osmotic concentration of the electrolyte, since the electrolyte molecules are dissociated by ions, as a result of which the concentration of kinetically active particles increase, which determines the magnitude of the osmotic concentration.

Osmotic pressure that can be resolved a solution containing 1 osmol equal to 22.4 atm. Therefore, osmotic pressure can be expressed in atmospheres or millimeters of a mercury pillar.

The osmotic plasma concentration is equal to 285 - 310 MOS (on average 300 mosm or 0.3 osm), it is one of the toughest parameters of the inner medium, its constancy is supported by the system of aczoregulation with the participation of hormones and change behavior - the emergence of the feeling of thirst and search for water.

Part of the total osmotic pressure due to proteins is called colloid-osmotic (oncotic) blood plasma pressure. Oncotic pressure is 25 - 30 mm RT. Art. The main physiological role of oncotic pressure is to hold water in the internal environment.

An increase in the osmotic concentration of the inner medium leads to the transition of water from the cells to the intercellular fluid and blood, the cells are wrinkled and their functions are broken. Reducing the concentration concentrations to the fact that water goes into cells, the cells swell, their membrane is destroyed, plasmolysis occurs due to the swelling of blood cells is called hemolysis. Hemolysis is the destruction of the shell of the most numerous blood cells - erythrocytes with a hemoglobin output in a plasma, which is painted in the red color and becomes transparent (lacquer blood). Hemolysis can be caused not only to a decrease in osmotic blood concentration. Distinguish the following types of hemolysis:

1. Osmotic hemolysis is developing with a decrease in osmotic pressure. Swelling occurs, then the destruction of red blood cells.

2. Chemical hemolysis is under the influence of substances that destroy the protein-lipid erythrocyte shell (ether, chloroform, alcohol, benzene, bile acids, saponin, etc.).

3. Mechanical hemolysis occurs with strong mechanical impacts on blood, for example, strong shaking ampoules with blood.

4. Thermal hemolysis is due to freezing and blood defrosting.

5. Biological hemolysis develops when overflowing incompatible blood, in the bite of some snakes, under the influence of immune hemolynsov, etc.

In this section, we will focus more on the mechanism of osmotic hemolysis. To do this, clarify such concepts as isotonic, hypotonic and hypertonic solutions. Isotonic solutions have a total concentration of ions not exceeding 285-310 mmol. This can be a 0.85% sodium chloride solution (it is often referred to as a "physiological" solution, although this does not fully reflect the situation), 1.1% solution of potassium chloride, 1.3% sodium bicarbonate solution, 5.5% glucose solution and etc. Hypotonic solutions have a smaller concentration of ions - less than 285 mmol. Hypertensive, on the contrary, greater - above 310 mmol. Erythrocytes are known in isotonic solution do not change its volume. In hypertonic solution - reduce it, and hypotonic - increase its volume in proportion to the degree of hypotension, up to the rupture of the erythrocyte (hemolysis) (Fig. 2).

Fig. 2. The state of the erythrocytes in the NaCl solution of various concentrations: in the hypotonic solution - osmotic hemolysis, in hypertonic -plasmolysis.

The phenomenon of osmotic hemolysis of erythrocytes is used in clinical and scientific practice in order to determine the qualitative characteristics of the erythrocytes (the method of determining the osmotic resistance of the erythrocytes), the stability of their membrane to destruction in the spitting solution.

Oncotic pressure

Part of the total osmotic pressure due to proteins is called colloid-osmotic (oncotic) blood plasma pressure. Oncotic pressure is 25 - 30 mm RT. Art. This is 2% of the total osmotic pressure.

Oncotic pressure to a greater extent depends on albumin (80% of oncotic pressure create albumin), which is associated with their relatively small molecular weight and large quantity Plasma molecules.

Oncotic pressure plays an important role in regulating water exchange. The more its value, the more water is held in the vascular bed and the less it goes into fabrics and vice versa. When a decrease in the concentration of protein in plasma, water ceases to be held in vascular bed and goes into tissues, edema develops.

Regulation of blood pH

pH is the concentration of hydrogen ions, expressed by the negative logarithm of the molar concentration of hydrogen ions. For example, pH \u003d 1 means that the concentration is equal to 101 mol / l; pH \u003d 7 - the concentration is 107 mol / l, or 100 nmol. The concentration of hydrogen ions significantly affects enzymatic activity, physiochemical properties Biomolecules and supramolecular structures. In the norm of blood pH corresponds to 7.36 (in arterial blood - 7.4; In venous blood - 7.34). The extreme limits of blood pH oscillations compatible with life - 7.0-7.7, or from 16 to 100 nmol / l.

In the process of metabolism in the body, a huge amount of "acidic products" is formed, which should lead to a pH shift in the acidic side. To a lesser extent, the body accumulates in the process of alkali metabolism, which can reduce the hydrogen content and shift the pH of the medium into the alkaline side - alkalosis. However, the reaction of blood under these conditions practically does not change, which is explained by the presence of buffer blood systems and neuro-reflex regulation mechanisms.

megaobuchalka.ru.

Tonicity is ... What is tonicity?

Tonicity (from τόνος - "voltage") - measure of the osmotic pressure gradient, that is, the differences in the aqueous potential of two solutions separated by a semi-permeable membrane. This concept is usually applied with respect to solutions surrounding cells. On osmotic pressure and tonicity can only affect solutions of substances that do not penetrate the membrane (electrolyte, protein, etc.). Solutions penetrating through the membrane have the same concentration on both sides, and, therefore, the tonicity does not change.

Classification

There are three versions of tonicity: one solution in relation to the other may be isotonic, hypertonic and hypotone.

Isotonic solutions

Schematic representation of erythrocyte in isotonic solution

Isotonia is the equality of osmotic pressure in liquid media and the tissues of the body, which is ensured by maintaining the osmotically equivalent concentrations of the substances contained in them. Isotonia is one of the most important physiological constants of the body provided by the mechanisms of self-regulation. Isotonic solution - a solution having an osmotic pressure equal to intracellular. Cell submersible in isotonic solution, It is in an equilibrium state - the water molecules diffuse through the cell membrane in an equal amount inside and outward, not accumulating and not lost by the cell. Deviation of osmotic pressure from normal physiological level There is a violation of the exchange processes between blood, fabric liquid and organism cells. Strong deviation can disrupt the structure and integrity of cell membranes.

Hypertensive solutions

Hypertensive solution is a solution having a large concentration of the substance relative to intracellular. When the cell immerses in a hypertensive solution, its dehydration occurs - intracellular water comes outward, which leads to drying and wrinkling the cell. Hypertensive solutions are applied when viewed for treatment internal hemorrhage.

Hypotonic solutions

The hypotonic solution is a solution having a smaller osmotic pressure relative to the other, that is, having a smaller concentration of a substance that does not penetrate through the membrane. When the cell immerses in the hypotonic solution, the osmotic penetration of water occurs inside the cell with the development of its hyperifurration - swelling with subsequent cytolysis. Vegetable cells In this situation, not always damage; When immersed in a hypotonic solution, the cell will increase the tour pressure, renewing its normal functioning.

Impact on cells

The epidermal cells of the tradescania are normal and in plasmolysis.

In animal cells, the hypertensive medium causes the output of water from the cell, causing cellular wrinkling (radar). In plants cells, the effects of hypertensive solutions are more dramatic. The flexible cell membrane departs from the cell wall, but it remains attached to it in the plasmodes area. Plasmolysis develops - cells acquire "needle" species, plasmodesma practically cease to function due to contraction.

Some organisms have specific mechanisms for overcoming hypertension ambient. For example, fish living in a hypertensive saline solution support intracellular osmotic pressure, actively highlighting the excess of the salt. This process is called osmoregulation.

In the hypotonic medium, animal cells swell up to break (cytolysis). To remove excess water in freshwater fish, the process of urination is constantly occurring. Vegetable cells are well resisting the effects of hypotonic solutions due to the durable cell wallproviding efficient osmolarity or osmolanity.

Some medications for intramuscular use It is preferable to introduce a slightly hypotonic solution in the form, which makes it possible to achieve their best absorption with tissues.