The main source of ATP in the cell. Biology lesson: ATP molecule - what is it. The role of ATP in the body

Continuation. See No. 11, 12, 13, 14, 15, 16/2005

Biology lessons in science classes

Advanced Planning, Grade 10

Lesson 19

Equipment: tables on general biology, a diagram of the structure of the ATP molecule, a diagram of the relationship between plastic and energy exchanges.

I. Knowledge Test

Conducting a biological dictation "Organic compounds of living matter"

The teacher reads the theses under the numbers, the students write down in the notebook the numbers of those theses that are suitable in content to their version.

Option 1 - proteins.
Option 2 - carbohydrates.
Option 3 - lipids.
Option 4 - nucleic acids.

1. In its pure form, they consist only of C, H, O atoms.

2. In addition to C, H, O atoms, they contain N and usually S atoms.

3. In addition to the C, H, O atoms, they contain N and P atoms.

4. They have a relatively small molecular weight.

5. The molecular weight can be from thousands to several tens and hundreds of thousands of daltons.

6. The largest organic compounds with a molecular weight of up to several tens and hundreds of millions of daltons.

7. They have different molecular weights - from very small to very high, depending on whether the substance is a monomer or a polymer.

8. Consist of monosaccharides.

9. Consist of amino acids.

10. Consist of nucleotides.

11. They are esters of higher fatty acids.

12. Basic structural unit: "nitrogenous base - pentose - phosphoric acid residue".

13. Basic structural unit: "amino acids".

14. Basic structural unit: "monosaccharide".

15. Basic structural unit: "glycerol-fatty acid".

16. Polymer molecules are built from the same monomers.

17. Polymer molecules are built from similar, but not exactly identical, monomers.

18. Are not polymers.

19. They perform almost exclusively energy, construction and storage functions, in some cases - protective.

20. In addition to energy and construction, they perform catalytic, signal, transport, motor and protective functions;

21. They store and transfer the hereditary properties of the cell and the body.

Option 1 – 2; 5; 9; 13; 17; 20.
Option 2 – 1; 7; 8; 14; 16; 19.
Option 3 – 1; 4; 11; 15; 18; 19.
Option 4– 3; 6; 10; 12; 17; 21.

II. Learning new material

1. The structure of adenosine triphosphoric acid

In addition to proteins, nucleic acids, fats and carbohydrates, a large number of other organic compounds are synthesized in living matter. Among them, an important role in the bioenergetics of the cell is played by adenosine triphosphate (ATP). ATP is found in all plant and animal cells. In cells, adenosine triphosphoric acid is most often present in the form of salts called adenosine triphosphates. The amount of ATP fluctuates and averages 0.04% (on average there are about 1 billion ATP molecules in a cell). The largest amount of ATP is found in skeletal muscles (0.2–0.5%).

The ATP molecule consists of a nitrogenous base - adenine, pentose - ribose and three residues of phosphoric acid, i.e. ATP is a special adenyl nucleotide. Unlike other nucleotides, ATP contains not one, but three phosphoric acid residues. ATP refers to macroergic substances - substances containing a large amount of energy in their bonds.

Spatial model (A) and structural formula (B) of the ATP molecule

From the composition of ATP under the action of ATPase enzymes, a residue of phosphoric acid is cleaved off. ATP has a strong tendency to detach its terminal phosphate group:

ATP 4– + H 2 O ––> ADP 3– + 30.5 kJ + Fn,

because this leads to the disappearance of the energetically unfavorable electrostatic repulsion between neighboring negative charges. The resulting phosphate is stabilized by the formation of energetically favorable hydrogen bonds with water. The charge distribution in the ADP + Fn system becomes more stable than in ATP. As a result of this reaction, 30.5 kJ are released (when a conventional covalent bond is broken, 12 kJ is released).

In order to emphasize the high energy "cost" of the phosphorus-oxygen bond in ATP, it is customary to denote it with the sign ~ and call it a macroenergetic bond. When one molecule of phosphoric acid is cleaved off, ATP is converted to ADP (adenosine diphosphoric acid), and if two molecules of phosphoric acid are cleaved off, then ATP is converted to AMP (adenosine monophosphoric acid). The cleavage of the third phosphate is accompanied by the release of only 13.8 kJ, so that there are only two macroergic bonds in the ATP molecule.

2. Formation of ATP in the cell

The supply of ATP in the cell is small. For example, in a muscle, ATP reserves are enough for 20–30 contractions. But a muscle can work for hours and produce thousands of contractions. Therefore, along with the breakdown of ATP to ADP, reverse synthesis must continuously occur in the cell. There are several pathways for the synthesis of ATP in cells. Let's get to know them.

1. anaerobic phosphorylation. Phosphorylation is the process of ATP synthesis from ADP and low molecular weight phosphate (Pn). In this case, we are talking about oxygen-free processes of oxidation of organic substances (for example, glycolysis is the process of oxygen-free oxidation of glucose to pyruvic acid). Approximately 40% of the energy released during these processes (about 200 kJ / mol of glucose) is spent on ATP synthesis, and the rest is dissipated in the form of heat:

C 6 H 12 O 6 + 2ADP + 2Fn -–> 2C 3 H 4 O 3 + 2ATP + 4H.

2. Oxidative phosphorylation- this is the process of ATP synthesis due to the energy of oxidation of organic substances with oxygen. This process was discovered in the early 1930s. 20th century V.A. Engelhardt. Oxygen processes of oxidation of organic substances proceed in mitochondria. Approximately 55% of the energy released in this case (about 2600 kJ / mol of glucose) is converted into the energy of chemical bonds of ATP, and 45% is dissipated in the form of heat.

Oxidative phosphorylation is much more efficient than anaerobic syntheses: if only 2 ATP molecules are synthesized during glycolysis during the breakdown of a glucose molecule, then 36 ATP molecules are formed during oxidative phosphorylation.

3. Photophosphorylation- the process of ATP synthesis due to the energy of sunlight. This pathway of ATP synthesis is characteristic only for cells capable of photosynthesis (green plants, cyanobacteria). The energy of sunlight quanta is used by photosynthetics in the light phase of photosynthesis for the synthesis of ATP.

3. Biological significance of ATP

ATP is at the center of metabolic processes in the cell, being the link between the reactions of biological synthesis and decay. The role of ATP in the cell can be compared with the role of a battery, since during the hydrolysis of ATP, the energy necessary for various life processes ("discharge") is released, and in the process of phosphorylation ("charging"), ATP again accumulates energy in itself.

Due to the energy released during ATP hydrolysis, almost all vital processes in the cell and body occur: transmission of nerve impulses, biosynthesis of substances, muscle contractions, transport of substances, etc.

III. Consolidation of knowledge

Solving biological problems

Task 1. When running fast, we often breathe, there is increased sweating. Explain these phenomena.

Task 2. Why do freezing people start stomping and jumping in the cold?

Task 3. In the well-known work by I. Ilf and E. Petrov "The Twelve Chairs" among many useful tips you can find the following: "Breathe deeply, you are excited." Try to justify this advice from the point of view of the energy processes occurring in the body.

IV. Homework

Start preparing for the test and test (dictate test questions - see lesson 21).

Lesson 20

Equipment: tables on general biology.

I. Generalization of the knowledge of the section

Work of students with questions (individually) with subsequent verification and discussion

1. Give examples of organic compounds that include carbon, sulfur, phosphorus, nitrogen, iron, manganese.

2. How can a living cell be distinguished from a dead one by ionic composition?

3. What substances are in the cell in an undissolved form? What organs and tissues do they include?

4. Give examples of macronutrients included in the active centers of enzymes.

5. What hormones contain trace elements?

6. What is the role of halogens in the human body?

7. How are proteins different from artificial polymers?

8. What is the difference between peptides and proteins?

9. What is the name of the protein that is part of hemoglobin? How many subunits does it consist of?

10. What is ribonuclease? How many amino acids are in it? When was it artificially synthesized?

11. Why is the rate of chemical reactions without enzymes low?

12. What substances are transported by proteins through the cell membrane?

13. How do antibodies differ from antigens? Do vaccines contain antibodies?

14. What substances break down proteins in the body? How much energy is released in this case? Where and how is ammonia neutralized?

15. Give an example of peptide hormones: how do they participate in the regulation of cellular metabolism?

16. What is the structure of sugar with which we drink tea? What other three synonyms for this substance do you know?

17. Why is fat in milk not collected on the surface, but is in suspension?

18. What is the mass of DNA in the nucleus of somatic and germ cells?

19. How much ATP is used by a person per day?

20. What proteins do people make clothes from?

Primary structure of pancreatic ribonuclease (124 amino acids)

II. Homework.

Continue preparation for the test and test in the section "Chemical organization of life."

Lesson 21

I. Conducting an oral test on questions

1. Elementary composition of the cell.

2. Characteristics of organogenic elements.

3. The structure of the water molecule. The hydrogen bond and its significance in the "chemistry" of life.

4. Properties and biological functions of water.

5. Hydrophilic and hydrophobic substances.

6. Cations and their biological significance.

7. Anions and their biological significance.

8. Polymers. biological polymers. Differences between periodic and non-periodic polymers.

9. Properties of lipids, their biological functions.

10. Groups of carbohydrates distinguished by structural features.

11. Biological functions of carbohydrates.

12. Elementary composition of proteins. Amino acids. The formation of peptides.

13. Primary, secondary, tertiary and quaternary structures of proteins.

14. Biological function of proteins.

15. Differences between enzymes and non-biological catalysts.

16. The structure of enzymes. Coenzymes.

17. The mechanism of action of enzymes.

18. Nucleic acids. Nucleotides and their structure. The formation of polynucleotides.

19. Rules of E.Chargaff. The principle of complementarity.

20. Formation of a double-stranded DNA molecule and its spiralization.

21. Classes of cellular RNA and their functions.

22. Differences between DNA and RNA.

23. DNA replication. Transcription.

24. Structure and biological role of ATP.

25. The formation of ATP in the cell.

II. Homework

Continue preparation for the test in the section "Chemical organization of life."

Lesson 22

I. Conducting a written test

Option 1

1. There are three types of amino acids - A, B, C. How many variants of polypeptide chains consisting of five amino acids can be built. Specify these options. Will these polypeptides have the same properties? Why?

2. All living things mainly consist of carbon compounds, and silicon, the analogue of carbon, the content of which in the earth's crust is 300 times more than carbon, is found only in very few organisms. Explain this fact in terms of the structure and properties of the atoms of these elements.

3. ATP molecules labeled with radioactive 32P at the last, third residue of phosphoric acid were introduced into one cell, and ATP molecules labeled with 32P at the first residue closest to ribose were introduced into another cell. After 5 minutes, the content of inorganic phosphate ion labeled with 32P was measured in both cells. Where will it be significantly higher?

4. Studies have shown that 34% of the total number of nucleotides of this mRNA is guanine, 18% is uracil, 28% is cytosine, and 20% is adenine. Determine the percentage composition of the nitrogenous bases of double-stranded DNA, of which the specified mRNA is a cast.

Option 2

1. Fats constitute the "first reserve" in energy metabolism and are used when the reserve of carbohydrates is exhausted. However, in skeletal muscles, in the presence of glucose and fatty acids, the latter are used to a greater extent. Proteins as a source of energy are always used only as a last resort, when the body is starving. Explain these facts.

2. Ions of heavy metals (mercury, lead, etc.) and arsenic are easily bound by sulfide groups of proteins. Knowing the properties of the sulfides of these metals, explain what happens to the protein when combined with these metals. Why are heavy metals poisonous to the body?

3. In the oxidation reaction of substance A into substance B, 60 kJ of energy is released. How many ATP molecules can be maximally synthesized in this reaction? How will the rest of the energy be used?

4. Studies have shown that 27% of the total number of nucleotides of this mRNA is guanine, 15% is uracil, 18% is cytosine, and 40% is adenine. Determine the percentage composition of the nitrogenous bases of double-stranded DNA, of which the specified mRNA is a cast.

To be continued

There are about 70 trillion cells in the human body. For healthy growth, each of them needs helpers - vitamins. Vitamin molecules are small, but their deficiency is always noticeable. If it is difficult to adapt to the dark, you need vitamins A and B2, dandruff has appeared - B12, B6, P are missing, bruises do not heal for a long time - vitamin C deficiency. In this lesson, you will learn how and where the strategic a supply of vitamins, how vitamins activate the body, and you will also learn about ATP - the main source of energy in the cell.

Topic: Fundamentals of Cytology

Lesson: The structure and functions of ATP

As you remember, nucleic acidsmade up of nucleotides. It turned out that nucleotides in a cell can be in a bound state or in a free state. In the free state, they perform a number of important functions for the life of the body.

To such free nucleotides applies ATP molecule or adenosine triphosphoric acid(adenosine triphosphate). Like all nucleotides, ATP is made up of a five-carbon sugar. ribose, nitrogenous base - adenine, and, unlike DNA and RNA nucleotides, three residues of phosphoric acid(Fig. 1).

Rice. 1. Three schematic representations of ATP

The most important ATP function is that it is a universal custodian and carrier energy in a cage.

All biochemical reactions in the cell that require energy expenditure use ATP as its source.

When separating one residue of phosphoric acid, ATP goes into ADP (adenosine diphosphate). If another phosphoric acid residue separates (which happens in special cases), ADP goes into AMF(adenosine monophosphate) (Fig. 2).

Rice. 2. Hydrolysis of ATP and its transformation into ADP

When separating the second and third residues of phosphoric acid, a large amount of energy is released, up to 40 kJ. That is why the bond between these phosphoric acid residues is called macroergic and is denoted by the corresponding symbol.

During the hydrolysis of an ordinary bond, a small amount of energy is released (or absorbed), and during the hydrolysis of a macroergic bond, much more energy (40 kJ) is released. The bond between ribose and the first residue of phosphoric acid is not macroergic; its hydrolysis releases only 14 kJ of energy.

Macroergic compounds can also be formed on the basis of other nucleotides, for example GTP(guanosine triphosphate) is used as an energy source in protein biosynthesis, takes part in signal transduction reactions, is a substrate for RNA synthesis during transcription, but it is ATP that is the most common and universal source of energy in the cell.

ATP contained as in the cytoplasm, and in the nucleus, mitochondria and chloroplasts.

Thus, we remembered what ATP is, what its functions are, and what a macroergic bond is.

Vitamins are biologically active organic compounds that are necessary in small quantities to maintain vital processes in the cell.

They are not structural components of living matter and are not used as an energy source.

Most vitamins are not synthesized in the human and animal body, but enter it with food, some are synthesized in small amounts by the intestinal microflora and tissues (vitamin D is synthesized by the skin).

The need for vitamins in humans and animals is not the same and depends on factors such as gender, age, physiological state and environmental conditions. Some vitamins are not needed by all animals.

For example, ascorbic acid, or vitamin C, is essential for humans and other primates. At the same time, it is synthesized in the body of reptiles (sailors took turtles on voyages to combat scurvy - vitamin C deficiency).

Vitamins were discovered at the end of the 19th century thanks to the work of Russian scientists N. I. Lunina and V. Pashutina, which showed that for good nutrition, it is necessary not only to have proteins, fats and carbohydrates, but also some other, at that time unknown, substances.

In 1912, a Polish scientist K. Funk(Fig. 3), studying the components of rice husk, which protects against Beri-Beri disease (avitaminosis of vitamin B), suggested that these substances must necessarily include amine groups. It was he who proposed to call these substances vitamins, that is, the amines of life.

Later it was found that many of these substances do not contain amino groups, but the term vitamins has taken root well in the language of science and practice.

As individual vitamins were discovered, they were designated in Latin letters and named depending on their functions. For example, vitamin E was called tocopherol (from ancient Greek τόκος - "childbirth", and φέρειν - "bring").

Today, vitamins are divided according to their ability to dissolve in water or in fats.

For water soluble vitamins include vitamins H, C, P, AT.

to fat-soluble vitamins refer A, D, E, K(can be remembered as a word: keda) .

As already noted, the need for vitamins depends on age, gender, physiological state of the organism and habitat. At a young age, there is a clear need for vitamins. A weakened body also requires large doses of these substances. With age, the ability to absorb vitamins decreases.

The need for vitamins is also determined by the body's ability to utilize them.

In 1912, a Polish scientist Casimir Funk received partially purified vitamin B1 - thiamine from rice husks. It took another 15 years to obtain this substance in a crystalline state.

Crystalline vitamin B1 is colorless, has a bitter taste and is readily soluble in water. Thiamine is found in both plant and microbial cells. Especially a lot of it in grain crops and yeast (Fig. 4).

Rice. 4. Thiamine Tablets and Foods

Heat treatment of foods and various additives destroy thiamine. With beriberi, pathologies of the nervous, cardiovascular and digestive systems are observed. Avitaminosis leads to disruption of water metabolism and hematopoiesis function. One of the clearest examples of thiamine deficiency is the development of Beri-Beri disease (Fig. 5).

Rice. 5. A person suffering from thiamine deficiency - beriberi disease

Vitamin B1 is widely used in medical practice for the treatment of various nervous diseases, cardiovascular disorders.

In baking, thiamine, along with other vitamins - riboflavin and nicotinic acid, is used to fortify bakery products.

In 1922 G. Evans and A. Bisho discovered a fat-soluble vitamin, which they called tocopherol or vitamin E (literally: “promoting childbirth”).

Vitamin E in its purest form is an oily liquid. It is widely distributed in cereals, such as wheat. It is abundant in vegetable and animal fats (Fig. 6).

Rice. 6. Tocopherol and products that contain it

A lot of vitamin E in carrots, eggs and milk. Vitamin E is antioxidant, that is, it protects cells from pathological oxidation, which leads them to aging and death. It is the "vitamin of youth". The importance of the vitamin for the reproductive system is enormous, so it is often called the reproduction vitamin.

As a result, vitamin E deficiency, first of all, leads to disruption of embryogenesis and reproductive organs.

The production of vitamin E is based on its isolation from wheat germ - by the method of alcohol extraction and distillation of solvents at low temperatures.

In medical practice, both natural and synthetic preparations are used - tocopherol acetate in vegetable oil, enclosed in a capsule (the famous "fish oil").

Vitamin E preparations are used as antioxidants for irradiation and other pathological conditions associated with an increased content of ionized particles and reactive oxygen species in the body.

In addition, vitamin E is prescribed for pregnant women, and is also used in complex therapy for the treatment of infertility, with muscular dystrophy and some liver diseases.

Vitamin A (Fig. 7) was discovered N. Drummond in 1916.

This discovery was preceded by observations of the presence of a fat-soluble factor in food, which is necessary for the full development of farm animals.

Vitamin A is right at the top of the vitamin alphabet. It is involved in almost all life processes. This vitamin is essential for restoring and maintaining good vision.

It also helps develop immunity to many diseases, including colds.

Without vitamin A, a healthy state of the skin epithelium is impossible. If you have goosebumps, which most often appears on the elbows, thighs, knees, legs, if you have dry skin on your hands or other similar phenomena, this means that you are deficient in vitamin A.

Vitamin A, like vitamin E, is necessary for the normal functioning of the sex glands (gonads). With hypovitaminosis of vitamin A, damage to the reproductive system and respiratory organs was noted.

One of the specific consequences of a lack of vitamin A is a violation of the process of vision, in particular, a decrease in the ability of the eyes to dark adaptation - night blindness. Avitaminosis leads to the occurrence of xerophthalmia and the destruction of the cornea. The latter process is irreversible, and is characterized by complete loss of vision. Hypervitaminosis leads to eye inflammation and hair loss, loss of appetite and complete exhaustion of the body.

Rice. 7. Vitamin A and foods that contain it

Group A vitamins are primarily found in animal products: in the liver, in fish oil, in oil, in eggs (Fig. 8).

Rice. 8. The content of vitamin A in products of plant and animal origin

Vegetable products contain carotenoids, which in the human body are converted into vitamin A by the action of the enzyme carotenoses.

Thus, today you got acquainted with the structure and functions of ATP, and also remembered the importance of vitamins and found out how some of them are involved in life processes.

With insufficient intake of vitamins in the body, primary vitamin deficiency develops. Different foods contain different amounts of vitamins.

For example, carrots contain a lot of provitamin A (carotene), cabbage contains vitamin C, etc. Hence the need for a balanced diet that includes a variety of plant and animal products.

Avitaminosis under normal nutritional conditions is very rare, much more common hypovitaminosis, which are associated with inadequate intake of vitamins with food.

Hypovitaminosis can occur not only as a result of an unbalanced diet, but also as a result of various pathologies of the gastrointestinal tract or liver, or as a result of various endocrine or infectious diseases that lead to malabsorption of vitamins in the body.

Some vitamins are produced by the intestinal microflora (gut microbiota). Suppression of biosynthetic processes as a result of action antibiotics may also lead to the development hypovitaminosis, as a consequence dysbacteriosis.

Excessive consumption of food vitamin supplements, as well as medicines containing vitamins, leads to the occurrence of a pathological condition - hypervitaminosis. This is especially true for fat-soluble vitamins, such as A, D, E, K.

Homework

1. What substances are called biologically active?

2. What is ATP? What is the structure of the ATP molecule? What types of chemical bonds exist in this complex molecule?

3. What are the functions of ATP in the cells of living organisms?

4. Where does ATP synthesis take place? Where does ATP hydrolysis take place?

5. What are vitamins? What are their functions in the body?

6. How are vitamins different from hormones?

7. What classifications of vitamins do you know?

8. What is avitaminosis, hypovitaminosis and hypervitaminosis? Give examples of these phenomena.

9. What diseases can be the result of insufficient or excessive intake of vitamins in the body?

10. Discuss your menu with friends and relatives, calculate, using additional information about the content of vitamins in different foods, whether you are getting enough vitamins.

1. A single collection of Digital Educational Resources ().

2. A single collection of Digital Educational Resources ().

3. A single collection of Digital Educational Resources ().

Bibliography

1. Kamensky A. A., Kriksunov E. A., Pasechnik V. V. General biology 10-11 class Bustard, 2005.

2. Belyaev D.K. Biology grade 10-11. General biology. A basic level of. - 11th ed., stereotype. - M.: Education, 2012. - 304 p.

3. Agafonova I. B., Zakharova E. T., Sivoglazov V. I. Biology 10-11 class. General biology. A basic level of. - 6th ed., add. - Bustard, 2010. - 384 p.

All living processes are based on atomic and molecular motion. Both the respiratory process and cellular development, division are impossible without energy. The source of energy supply is ATP, what it is and how it is formed, we will consider further.

Before studying the concept of ATP, it is necessary to decipher it. This term means nucleoside triphosphate, which is essential for energy and material metabolism in the body.

This is a unique energy source underlying biochemical processes. This compound is fundamental for enzymatic formation.

ATP was discovered at Harvard in 1929. The founders were scientists at Harvard Medical School. These included Karl Loman, Cyrus Fiske and Yellapragada Subbarao. They identified a compound that resembled the adenyl nucleotide of ribonucleic acids in structure.

A distinctive feature of the compound was the content of three phosphoric acid residues instead of one. In 1941, the scientist Fritz Lipmann proved that ATP has an energy potential within the cell. Subsequently, a key enzyme was discovered, which was called ATP synthase. Its task is the formation of acidic molecules in the mitochondria.

ATP is the energy accumulator in cell biology and is essential for the successful implementation of biochemical reactions.

The biology of adenosine triphosphoric acid suggests its formation as a result of energy metabolism. The process consists of creating 2 molecules in the second step. The remaining 36 molecules appear in the third stage.

The accumulation of energy in the structure of the acid occurs in the binder between the phosphorus residues. In the case of detachment of 1 phosphorus residue, an energy release of 40 kJ occurs.

As a result, the acid is converted to adenosine diphosphate (ADP). Subsequent phosphate detachment promotes the production of adenosine monophosphate (AMP).

It should be noted that the plant cycle involves the reuse of AMP and ADP, which results in the reduction of these compounds to an acid state. This is provided by the process.

Structure

Disclosure of the essence of the compound is possible after studying which compounds are part of the ATP molecule.

What compounds are in acid?

• 3 residues of phosphoric acid. Acid residues are combined with each other through energy bonds of an unstable nature. It is also found under the name orthophosphoric acid;
• adenine: Is a nitrogenous base;
• Ribose: It is a pentose carbohydrate.

The inclusion of these elements in ATP gives it a nucleotide structure. This allows the molecule to be classified as a nucleic acid.

Important! As a result of the splitting off of acid molecules, energy is released. The ATP molecule contains 40 kJ of energy.

Education

The formation of the molecule occurs in mitochondria and chloroplasts. The fundamental moment in the molecular synthesis of acid is the dissimilation process. Dissimilation is the process of transition of a complex compound to a relatively simple one due to destruction.

As part of the synthesis of acid, it is customary to distinguish several stages:

1. Preparatory. The basis of splitting is the digestive process, provided by the enzymatic action. The food that enters the body is destroyed. Fat is broken down into fatty acids and glycerol. Proteins are broken down into amino acids, starch is broken down into glucose. The stage is accompanied by the release of thermal energy.
2. Anoxic, or glycolysis. The process of disintegration is the basis. Glucose breakdown occurs with the participation of enzymes, while 60% of the released energy is converted into heat, the rest remains in the composition of the molecule.
3. Oxygen, or hydrolysis; Occurs within the mitochondria. Occurs with the help of oxygen and enzymes. The oxygen exhaled by the body is involved. Ends complete. It implies the release of energy to form a molecule.

There are the following ways of molecular formation:

1. Phosphorylation of a substrate nature. Based on the energy of substances as a result of oxidation. The prevailing part of the molecule is formed in mitochondria on membranes. It is carried out without the participation of membrane enzymes. It takes place in the cytoplasmic part through glycolysis. The option of formation due to the transportation of a phosphate group from other high-energy compounds is allowed.
2. Phosphorylation of an oxidative nature. Occurs due to an oxidative reaction.
3. Photophosphorylation in plants during photosynthesis.

Meaning

The fundamental importance of the molecule for the body is revealed through the function of ATP.

ATP functionality includes the following categories:

1. Energy. Provides the body with energy, is the energy basis of physiological biochemical processes and reactions. Occurs due to 2 high-energy bonds. It implies muscle contraction, the formation of a transmembrane potential, the provision of molecular transport through membranes.
2. basis of synthesis. It is considered the starting compound for the subsequent formation of nucleic acids.
3. Regulatory. Underlies the regulation of most biochemical processes. Provided by belonging to the allosteric effector of the enzymatic series. It affects the activity of regulatory centers by strengthening or suppressing them.
4. Intermediary. It is considered a secondary link in the transmission of a hormonal signal to the cell. It is a precursor to the formation of cyclic ADP.
5. mediator. It is a signaling substance in synapses and other cellular interactions. Provides purinergic signaling.

Among the above points, the dominant place is given to the energy function of ATP.

It is important to understand, no matter what function ATP performs, its value is universal.

Useful video

Summing up

The basis of physiological and biochemical processes is the existence of the ATP molecule. The main task of the connections is energy supply. Without connection, the vital activity of both plants and animals is impossible.

In contact with

ATP, or adenosine triphosphoric acid in full, is the "accumulator" of energy in the cells of the body. Not a single biochemical reaction takes place without the participation of ATP. ATP molecules are found in DNA and RNA.

Composition of ATP

The ATP molecule has three components: three phosphoric acid residues, adenine and ribose. That is, ATP has the structure of a nucleotide and refers to nucleic acids. Ribose is a carbohydrate and adenine is a nitrogenous base. The remains of the acid are united with each other by unstable energy bonds. Energy appears when acid molecules are split off. The separation occurs due to biocatalysts. After detachment, the ATP molecule is already converted into ADP (if one molecule is cleaved off) or AMP (if two acid molecules are cleaved off). With the separation of one molecule of phosphoric acid, 40 kJ of energy is released.

Role in the body

ATP plays not only an energy role in the body, but also a number of others:

• is the result of the synthesis of nucleic acids.
• regulation of many biochemical processes.
• signaling substance in other cell interactions.

ATP synthesis

ATP production takes place in chloroplasts and mitochondria. The most important process in the synthesis of ATP molecules is dissimilation. Dissimilation is the destruction of the complex to the simpler.

The synthesis of ATP does not take place in one stage, but in three stages:

1. The first stage is preparatory. Under the action of enzymes in digestion, the decay of what we have absorbed occurs. In this case, fats decompose to glycerol and fatty acids, proteins to amino acids, and starch to glucose. That is, everything is prepared for further use. Thermal energy is released
2. The second step is glycolysis (anoxic). The breakdown occurs again, but here the glucose is also degraded. Enzymes are also involved. But 40% of the energy remains in ATP, and the rest is spent as heat.
3. The third stage is hydrolysis (oxygen). It occurs already in the mitochondria themselves. Here, both the oxygen that we inhale and enzymes take part. After complete dissimilation, energy is released for the formation of ATP.

Millions of biochemical reactions take place in any cell of our body. They are catalyzed by a variety of enzymes that often require energy. Where does the cell take it? This question can be answered if we consider the structure of the ATP molecule - one of the main sources of energy.

ATP is a universal source of energy

ATP stands for adenosine triphosphate, or adenosine triphosphate. Matter is one of the two most important sources of energy in any cell. The structure of ATP and the biological role are closely related. Most biochemical reactions can only take place with the participation of molecules of a substance, especially this applies. However, ATP is rarely directly involved in the reaction: for any process to occur, energy is needed that is contained precisely in adenosine triphosphate.

The structure of the molecules of the substance is such that the bonds formed between the phosphate groups carry a huge amount of energy. Therefore, such bonds are also called macroergic, or macroenergetic (macro=many, large number). The term was first introduced by the scientist F. Lipman, and he also suggested using the icon ̴ to designate them.

It is very important for the cell to maintain a constant level of adenosine triphosphate. This is especially true for the cells of muscle tissue and nerve fibers, because they are the most energy-dependent and need a high content of adenosine triphosphate to perform their functions.

The structure of the ATP molecule

Adenosine triphosphate is made up of three elements: ribose, adenine, and

Ribose- a carbohydrate that belongs to the group of pentoses. This means that ribose contains 5 carbon atoms, which are enclosed in a cycle. Ribose is connected to adenine by a β-N-glycosidic bond on the 1st carbon atom. Also, phosphoric acid residues on the 5th carbon atom are attached to the pentose.

Adenine is a nitrogenous base. Depending on which nitrogenous base is attached to the ribose, GTP (guanosine triphosphate), TTP (thymidine triphosphate), CTP (cytidine triphosphate) and UTP (uridine triphosphate) are also isolated. All these substances are similar in structure to adenosine triphosphate and perform approximately the same functions, but they are much less common in the cell.

Residues of phosphoric acid. A maximum of three phosphoric acid residues can be attached to a ribose. If there are two or only one of them, then, respectively, the substance is called ADP (diphosphate) or AMP (monophosphate). It is between the phosphorus residues that macroenergetic bonds are concluded, after the rupture of which from 40 to 60 kJ of energy is released. If two bonds are broken, 80, less often - 120 kJ of energy is released. When the bond between the ribose and the phosphorus residue is broken, only 13.8 kJ is released, therefore, there are only two high-energy bonds in the triphosphate molecule (P ̴ P ̴ P), and one in the ADP molecule (P ̴ P).

What are the structural features of ATP. Due to the fact that a macroenergetic bond is formed between phosphoric acid residues, the structure and functions of ATP are interconnected.

The structure of ATP and the biological role of the molecule. Additional functions of adenosine triphosphate

In addition to energy, ATP can perform many other functions in the cell. Along with other nucleotide triphosphates, triphosphate is involved in the construction of nucleic acids. In this case, ATP, GTP, TTP, CTP and UTP are the suppliers of nitrogenous bases. This property is used in processes and transcription.

ATP is also required for the operation of ion channels. For example, the Na-K channel pumps 3 molecules of sodium out of the cell and pumps 2 molecules of potassium into the cell. Such an ion current is needed to maintain a positive charge on the outer surface of the membrane, and only with the help of adenosine triphosphate can the channel function. The same applies to proton and calcium channels.

ATP is the precursor of the second messenger cAMP (cyclic adenosine monophosphate) - cAMP not only transmits the signal received by the cell membrane receptors, but is also an allosteric effector. Allosteric effectors are substances that speed up or slow down enzymatic reactions. So, cyclic adenosine triphosphate inhibits the synthesis of an enzyme that catalyzes the breakdown of lactose in bacterial cells.

The adenosine triphosphate molecule itself can also be an allosteric effector. Moreover, in such processes, ADP acts as an ATP antagonist: if triphosphate accelerates the reaction, then diphosphate slows down, and vice versa. These are the functions and structure of ATP.

How is ATP formed in the cell

The functions and structure of ATP are such that the molecules of the substance are quickly used and destroyed. Therefore, the synthesis of triphosphate is an important process in the formation of energy in the cell.

There are three most important ways to synthesize adenosine triphosphate:

1. Substrate phosphorylation.

2. Oxidative phosphorylation.

3. Photophosphorylation.

Substrate phosphorylation is based on multiple reactions occurring in the cytoplasm of the cell. These reactions are called glycolysis - the anaerobic stage. As a result of 1 glycolysis cycle, two molecules are synthesized from 1 glucose molecule, which are further used for energy production, and two ATP are also synthesized.

• C 6 H 12 O 6 + 2ADP + 2Fn --> 2C 3 H 4 O 3 + 2ATP + 4H.

Cell respiration

Oxidative phosphorylation is the formation of adenosine triphosphate by the transfer of electrons along the electron transport chain of the membrane. As a result of this transfer, a proton gradient is formed on one of the sides of the membrane, and with the help of the protein integral set of ATP synthase, molecules are built. The process takes place on the mitochondrial membrane.

The sequence of steps of glycolysis and oxidative phosphorylation in mitochondria makes up the overall process called respiration. After a complete cycle, 36 ATP molecules are formed from 1 glucose molecule in the cell.

Photophosphorylation

The process of photophosphorylation is the same oxidative phosphorylation with only one difference: photophosphorylation reactions occur in the chloroplasts of the cell under the action of light. ATP is produced during the light stage of photosynthesis, the main energy-producing process in green plants, algae, and some bacteria.

In the process of photosynthesis, electrons pass through the same electron transport chain, resulting in the formation of a proton gradient. The concentration of protons on one side of the membrane is the source of ATP synthesis. The assembly of molecules is carried out by the enzyme ATP synthase.

The average cell contains 0.04% adenosine triphosphate of the total mass. However, the highest value is observed in muscle cells: 0.2-0.5%.

There are about 1 billion ATP molecules in a cell.

Each molecule lives no more than 1 minute.

One molecule of adenosine triphosphate is renewed 2000-3000 times a day.

In total, the human body synthesizes 40 kg of adenosine triphosphate per day, and at each time point the supply of ATP is 250 g.

Conclusion

The structure of ATP and the biological role of its molecules are closely related. The substance plays a key role in life processes, because the macroergic bonds between phosphate residues contain a huge amount of energy. Adenosine triphosphate performs many functions in the cell, and therefore it is important to maintain a constant concentration of the substance. Decay and synthesis proceed at a high speed, since the energy of bonds is constantly used in biochemical reactions. It is an indispensable substance of any cell of the body. That, perhaps, is all that can be said about the structure of ATP.