Carbohydrates and carbohydrate metabolism. Presentation on the topic: "Food addiction" glucose transfer is possible against a concentration gradient

Carbohydrates - polyhydric
aldehyde alcohols or keto alcohols.
For most carbohydrates the general formula is
(CH2O)n, n>3 – compounds of carbon with water.
Empirical formula for glucose
C6H12O6=(CH2O)6
Carbohydrates are the basis for the existence of most
organisms, because all organic matter is taken
originates from carbohydrates formed in
photosynthesis. There are more carbohydrates in the biosphere
than other organic substances.

Biological role of carbohydrates

Energy (decay)
Plastic (chondroitin sulfate)
Reserve (glycogen)
Protective (membranes, joint lubrication)
Regulatory (contacts)
Hydroosmotic (GAG)
Cofactor (heparin)
Specific (receptors)

Classification of carbohydrates

Depending on complexity
buildings are divided into 3 classes:
monosaccharides
oligosaccharides
polysaccharides

Monosaccharides

MONOSACHARIDE (MONOSA) – minimal
structural unit of carbohydrates, with
crushing of which the properties disappear
sugars
Depending on the number of atoms
carbon in a molecule
monosaccharides are divided into: trioses (C3H6O3),
tetroses (C4H8O4), pentoses (C5H10O5), hexoses
(C6H12O6) and heptose (C7H14O7).
There are no other monosaccharides in nature, but they can
be synthesized.

Physiologically important
monosaccharides:
1) Trioses - PHA and DOAP are formed
during the breakdown of glucose
2) Pentoses - ribose and deoxyribose,
are important components
nucleotides, nucleic acids,
coenzymes
3) Hexoses – glucose, galactose,
fructose and mannose. Glucose and
fructose is the main energy source
substrates of the human body

Molecular composition of glucose and fructose
is the same (C6H12O6),
but the structure of functional groups is different
(aldose and ketose)

Monosaccharides are less common in
living organisms in a free state,
than their more important derivatives -
oligosaccharides and polysaccharides

OLIGOSACHARIDES

include from 2 to 10 residues
monosaccharides, connected
1,4- or 1,2-glycosidic bonds,
formed between two alcohols with
by obtaining ethers: R-O-R".
Main disaccharides –
sucrose, maltose and lactose.
Their molecular formula is C12H22O12.

Sucrose (cane or beet sugar) –

These are glucose and fructose,
linked by a 1,2-glycosidic bond
The enzyme sucrase breaks down sucrose.

Maltose (fruit sugar)

These are 2 glucose molecules connected
1,4-glycosidic bond. Formed in
Gastrointestinal tract during hydrolysis of starch and glycogen
food. Breaks down with maltase.

Lactose (milk sugar)

These are molecules of glucose and galactose,
connected by a 1,4-glycosidic bond.
Synthesized during lactation.
The intake of lactose from food contributes to
development of lactic acid bacteria,
suppressing the development of putrefactive
processes. Breaks down with lactase.

POLYSACCHARIDES

Most natural carbohydrates are polymers
number of monosaccharide residues
from 10 to tens of thousands.
According to functional properties:
structural – give to cells, organs and
the whole body mechanical strength.
hydrophilic soluble – highly hydrated and prevent cells and tissues from drying out.
reserve – an energy resource from which
the body receives monosaccharides, which are
cellular fuel.
Due to the polymeric nature, reserve
polysaccharides are osmotically inactive, therefore
accumulate in cells in large quantities.

By structure: linear, branched
Composition: homo-, heteropolysaccharides
Homopolysaccharides (homoglycans)
consist of monosaccharide units of the same type.,
The main representatives are starch, glycogen,
cellulose.
Starch is a reserve nutrient
plants, consists of amylose and amylopectin.
The products of starch hydrolysis are called
dextrins. They come in different lengths and
shortening gradually loses iodophilicity
(ability to stain with iodine in Blue colour).

Amylose has a linear structure,
all glucose residues are connected by a (1-4) glycosidic bond. Contains amylose
≈ 100-1000 glucose residues.
Makes up ≈ 15-20% of total starch.

Amylopectin is branched because has through
every 24-30 glucose residues
a small number of alpha(1-6) bonds.
Amylopectin contains ≈ 600-6000 residues
glucose, molecular weight up to 3 million.
Amylopectin content in starch –
75-85%

Fiber (cellulose)
main component of the cell wall
plants. Consists of ≈ 2000-11000 residues
glucose, connected, unlike starch, not by an α-, but by a β-(1-4)-glycosidic bond.

Glycogen – animal starch

Contains from 6,000 to 300,000 residues
glucose. More branched structure
than amylopectin: 1-6 bonds in glycogen
every 8-11 glucose residues connected by a 1-4 bond. Backup source
energy - stored in the liver, muscles, heart.

Heteropolysaccharides (heteroglycans)

These are complex carbohydrates, made up of two
more types of monosaccharide units
(amino sugars and uronic acids),
most often associated with proteins or lipids
Glycosaminoglycans (mucopolysaccharides)
chondroitin-, keratan- and dermatan sulfates,
hyaluronic acid, heparin.
Presented as part of the main fastening agent
substances connective tissue. Their function
consists in holding large quantity water and
filling the intercellular space. They
serve as a softening and lubricant for
various types of tissue structures that are part of
bone and dental tissues

Hyaluronic acid is a linear polymer of
glucuronic acid and acetylglucosamine.
Included in cell walls, synovial
liquids, vitreous eyes, envelops
internal organs, is jelly-like
bactericidal lubricant. Important component
element of skin, cartilage, tendons, bones, teeth...
main substance of postoperative scars
(adhesions, scars – drug “hyaluronidase”)

Chondroitin sulfates –

branched sulfated polymers from
glucuronic acid and N-acetylglucosamine.
Basic structural components cartilage,
tendons, cornea of the eye, contained in the skin,
bones, teeth, periodontal tissues.

The norm of carbohydrates in the diet

The reserve of carbohydrates in the body does not exceed
2-3% of body weight.
Due to them, energy needs
a person can be covered for no more than 12-14 hours.
The body's need for glucose depends
on the level of energy consumption.
The minimum carbohydrate intake is 400 g per day.
65% of carbohydrates come in the form of starch
(bread, cereals, pasta), animal
glycogen
35% in the form of simpler sugars (sucrose,
lactose, glucose, fructose, honey, pectin
substances).

Digestion of carbohydrates
Digestion is distinguished:
1) cavity
2) wall
The mucous membrane of the gastrointestinal tract -
natural barrier to entry
into the body of large foreign
molecules, including carbohydrates
nature

The absorption of oligo- and polysaccharides occurs during their hydrolytic breakdown into monosaccharides. Glycosidases attack 1-4 and 1-6 glycosidic bonds. About

Assimilation of oligo- and
polysaccharides comes with their
hydrolytic breakdown to monosaccharides.
Glycosidases attack
1-4 and 1-6 glycosidic bonds
Simple carbohydrates
digestion is not
are exposed, but may
fermentation occurs
some part of the molecules
in the large intestine under
action of enzymes
microorganisms
.
.

CAVITY DIGESTION
Digestion of polysaccharides begins in oral cavity, where they are subjected to the chaotic action of amylase
saliva along (1-4)-bonds. Starch breaks down into dextrins of varying complexity.
In salivary amylase (activated by Cl ions),
optimum pH=7.1-7.2 (in slightly alkaline
environment). In the stomach, where the environment is sharply acidic,
starch can only be digested in
depth of the food bolus. Pepsin gastric juice breaks down amylase itself.

Next, the food passes into the intestines, where the pH
neutral and exposed to
1) pancreatic amylase.
There are -, β-, γ-amylases
Alpha amylase is more widely represented, breaks down starch into dextrins
Beta amylase breaks down
dextrins to maltose disaccharide
Gamma amylase cleaves
individual terminal glucose molecules
from starch or dextrins
2) oligo-1,6-glucosidase - acts on
branch points of starch and glycogen

WALL DIGESTION

Hydrolysis of disaccharides occurs
not in the intestinal lumen,
and on the surface of mucosal cells
shell under a special thin
film - glycocalyx
Disaccharides are broken down here by
action of lactase (enzyme in
composition
β-glycosidase complex), sucrase and
maltase. In this case,
monosaccharides - glucose, galactose,
fructose.

Cellulose in the human body

Humans do not have enzymes to break down
β(1-4)-glycosidic bond of cellulose.
The microflora of the large intestine can hydrolyze most pulp to
cellobiose and glucose.
Functions of cellulose:
1) stimulation of intestinal motility and
bile secretion,
2) adsorption of a number of substances (cholesterol, etc.)
with a decrease in their absorption,
3) formation feces.

Only monosaccharides are absorbed in the intestine

Their transfer into mucosal cells
intestinal lining (enterocytes)
may happen:
1) by passive diffusion method
along a concentration gradient
from the intestinal lumen (where the concentration of sugar after eating is higher)
into the intestinal cells (where it is lower).

2) glucose transfer is also possible against a concentration gradient.

This is active transport: it comes with a cost
energy, special
carrier proteins (GLUT).
Glucose
Carrier protein + ATP

MAIN SOURCES OF GLUCOSE

1) food;
2) breakdown of glycogen;
3) synthesis of glucose from non-carbohydrates
precursors (gluconeogenesis).

MAIN WAYS OF USING GLUCOSE

1) breakdown of glucose to produce
energy (aerobic and anaerobic
glycolysis);
2) glycogen synthesis;
3) pentose phosphate breakdown pathway for
obtaining other monosaccharides and
reduced NADPH;
4) synthesis of other compounds (fatty
acids, amino acids,
heteropolysaccharides, etc.).

SOURCES AND WAYS OF GLUCOSE CONSUMPTION

Glycogen is formed in almost all
body cells, but
its maximum concentration
in the liver (2-6%) and muscles (0.5-2%)
Muscle mass is significantly greater
liver mass, therefore
skeletal muscles concentrated
about 2/3 of the total
total body glycogen

GLYCOGENOLYSIS

Glycogen breakdown can occur when
lack of oxygen. This is a transformation
glycogen into lactic acid.
Glycogen is present in cells in the form
granules that contain enzymes
synthesis, breakdown and enzyme regulation.
The reactions of synthesis and decomposition are different, which
provides process flexibility.

Molecule split off from glycogen
glucose-1-P isomerizes
with the formation of glucose-6-P
glucose-1-P
phosphogluco mutase
glucose-6-P
When the cell itself needs energy, glucose-6-P breaks down along the path of glycolysis.
If glucose is needed by other cells, then
glucose-6-phosphatase (only in the liver and
kidneys) splits phosphate from glucose-6-P,
and glucose enters the bloodstream.

GLYCOLYSIS

Glycolysis (Greek glucose - sugar, lysis -
destruction) – sequence
reactions converting glucose to
pyruvate (10 reactions).
During glycolysis, part of the free
glucose breakdown energy is converted
in ATP and NADH.
Total reaction of glycolysis:
Glucose + 2 pH + 2 ADP + 2 NAD+→
2 pyruvate + 2 ATP + 2 NADH + 2H+ + 2
H2O

Anaerobic GLYCOLYSIS

This is the main anaerobic pathway
glucose utilization
1) Occurs in all cells
2) For red blood cells - the only one
energy source
3) Prevails in tumor cells –
source of acidosis
There are 11 reactions in glycolysis,
the product of each reaction is
substrate for the next one.
The end product of glycolysis is lactate.

AEROBIC AND ANAEROBIC DECOMPOSITION OF GLUCOSE

Anaerobic glycolysis, or anaerobic breakdown
glucose, (these terms are synonyms) includes
reactions of a specific pathway of glucose breakdown to
pyruvate and the reduction of pyruvate to lactate. ATP
in anaerobic glycolysis it is formed only by
substrate phosphorylation
Aerobic breakdown of glucose to final products
(CO2 and H2O) includes aerobic reactions
glycolysis and subsequent oxidation of pyruvate to
general path of catabolism.
Thus, aerobic breakdown of glucose is a process
its complete oxidation to CO2 and H2O, and aerobic
Glycolysis is part of the aerobic breakdown of glucose.

ENERGY BALANCE OF AEROBIC OXIDATION OF GLUCOSE

1. In a specific breakdown pathway, glucose is formed
2 molecules of pyruvate, 2 ATP (substrate
phosphorylation) and 2 molecules of NADH+H+.
2. Oxidative decarboxylation of each
pyruvate molecules - 2.5 ATP;
decarboxylation of 2 molecules of pyruvate gives 5
ATP molecules.
3. As a result of oxidation of the acetyl group
acetyl-CoA in the TCA cycle and conjugated CPE – 10 ATP;
2 molecules of acetyl-CoA form 20 ATP.
4. Malate shuttle mechanism transfers
NADH+H+ in mitochondria – 2.5 ATP; 2 NADH+H+
form 5 ATP.
Total: with the breakdown of 1 glucose molecule into
under aerobic conditions 32 molecules are formed
ATF!!!

Gluconeogenesis

Gluconeogenesis – synthesis of glucose
de novo from non-carbohydrate components.
Occurs in the liver and ≈10% in the kidneys.
Predecessors for
gluconeogenesis
lactate (main),
glycerol (second),
amino acids (third) – under conditions
long fasting.

Places of entry of substrates (precursors) for gluconeogenesis

RELATIONSHIP OF GLYCOLYSIS AND GLUCONEOGENESIS

1. The main substrate for gluconeogenesis is
lactate formed by active skeletal
muscle. Plasma membrane has
high permeability to lactate.
2. Once lactate enters the bloodstream, it is transported to the liver,
where in the cytosol it is oxidized to pyruvate.
3. Pyruvate is then converted to glucose along the way
gluconeogenesis.
4. Glucose then enters the blood and is absorbed
skeletal muscles. These transformations
constitute the Cori cycle.

MEASLES CYCLE

Glucose-alanine cycle

CHARACTERISTICS OF THE PENTOSOPHOSPHATE PATHWAY

Pentose phosphate pathway of glucose breakdown (PGP)
also called hexose monophosphate shunt or
phosphogluconate pathway.
This alternative oxidation pathway to glycolysis and the TCA cycle
glucose was described in the 50s of the twentieth century by F. Dickens,
B. Horeker, F. Lipmann and E. Racker.
Enzymes of the pentose phosphate pathway are localized in
cytosol. PFP is most active in the kidneys,
liver, adipose tissue, adrenal cortex,
erythrocytes, lactating mammary gland. IN
Most of these tissues undergo a process
biosynthesis of fatty acids and steroids, which requires
NADPH.
There are two phases of PPP: oxidative and
non-oxidative

FUNCTIONS OF THE PENTOSOPHOSPHATE PATHWAY

1. Formation of NADPH+H+ (50% of the body’s needs),
necessary 1) for the biosynthesis of fatty acids,
cholesterol and 2) for the detoxification reaction
(reduction and oxidation of glutathione,
functioning of cytochrome P-450 dependent
monooxygenases – microsomal oxidation).
2. Synthesis of ribose 5-phosphate, used for
formation of 5-phosphoribosyl-1-pyrophosphate, which
necessary for the synthesis of purine nucleotides and
addition of orotic acid during biosynthesis
pyrimidine nucleotides.
3. Synthesis of carbohydrates with different numbers of atoms
carbon (C3-C7).
4. In plants, the formation of ribulose-1,5-bisphosphate,
which is used as a CO2 acceptor in the dark
stages of photosynthesis.

Oxidative decarboxylation of pyruvate -

Oxidative
decarboxylation of pyruvate is the formation of acetyl~CoA from PVC –
key irreversible stage
metabolism!!!
Upon decarboxylation 1
pyruvate molecules are released 2.5
ATP.
Animals are not capable of transforming
acetyl~CoA
back to glucose.
acetyl~CoA goes into the tricarboxylic cycle
acids (TCA)

Tricarboxylic acid cycle

cycle citric acid
Krebs cycle
Hans Krebs - Nobel laureate
awards 1953
TCA reactions occur
in mitochondria

CTK
1) final common path oxidation
fuel molecules -
fatty acids, carbohydrates, amino acids.
Most fuel molecules
enter this cycle after becoming
acetyl~CoA.
2) The TsTK performs one more function -
supplies intermediate products
for biosynthesis processes.

Role of the TTC

energy value
source of important metabolites,
giving rise to new metabolic pathways
(gluconeogenesis, transamination and
deamination of amino acids,
synthesis of fatty acids, cholesterol)
The following compounds are vitally important:
oxaloacetate (OAK) and α-ketoglutaric acid.
They are precursors to amino acids.
First, malate and
isocitrate, and from them are then formed in the cytoplasm
SHUK and α-KG. Then, under the influence of transaminases from Pike
aspartate is formed, and from alpha-CG - glutamate.
As a result of the oxidation of the acetyl group of acetylCoA in the TCA cycle and conjugated CPE - 10 ATP!!!

Disorders of carbohydrate metabolism with:

- fasting
hypoglycemia, glucagon and adrenaline mobilize
TAG and gluconeogenesis from glycerol, FFAs go to
formation of acetyl-CoA and ketone bodies
- stress
influence of catecholamines (adrenaline - breakdown
glycogen, gluconeogenesis); glucocorticoids
(cortisol - synthesis of gluconeogenesis enzymes)
- insulin-dependent diabetes mellitus
decreased insulin synthesis in β-cells
pancreas →cascade of effects

Hyperglycemia, and after overcoming the renal
threshold - glucosuria occurs
Reduced transport of glucose into the cell (including
due to ↓ synthesis of GLUT molecules)
Reduced glycolysis (including aerobic
processes) and the cell lacks energy
(including for protein synthesis, etc.)
Inhibition of the pentose phosphate pathway
Glycogen synthesis is reduced and constantly
glycogen breakdown enzymes are activated
Gluconeogenesis is constantly activated (especially from
glycerol, the excess goes to ketone bodies)
Pathways unregulated by insulin are activated
glucose uptake in the cell: glucuronate pathway
GAG formation, glycoprotein synthesis
(including excessive glycosylation
proteins), reduction to sorbate, etc. summary of other presentations

“Stages of energy metabolism” - Types of nutrition of organisms. The relationship between anabolism and catabolism. Presence of intact mitochondrial membranes. The splitting process. Oxidative decarboxylation. Fill in the blanks in the text. Aerobic respiration. Glycolysis. Sun. Stages of energy metabolism. Energy release. Conditions. Solar energy. Oxygen-free stage. How many glucose molecules need to be broken down? Stages of aerobic respiration.

““Energy metabolism” 9th grade” - The concept of energy metabolism. Glucose is the central molecule of cellular respiration. Mitochondria. Diagram of the stages of energy metabolism. Energy metabolism(dissimilation). Fermentation. Conversion of ATP to ADP. PVA – pyruvic acid C3H4O3. ATP composition. Three stages of energy metabolism. Structure of ATP. Fermentation is anaerobic respiration. Summary equation of the aerobic phase. ATP is a universal source of energy in the cell.

“Carbohydrate metabolism” - Involvement of carbohydrates in glycolysis. Scheme of glucose oxidation. Aldolaza. Important coenzymes. Metabolism. Hans Krebs. Anaerobic glycolysis. Sucrose. Glycogen synthesis. Summary of the Krebs cycle. Glucokinase. Mitochondria. Enzymes. Electron transport chain. Electron transfer. Enzymes. Phosphoglucoisomerase. Substrate phosphorylation. Oxidation of acetyl-CoA to CO2. Protein components of the mitochondrial ETC. Catabolism.

“Metabolism and cell energy” - Metabolism. A task with a detailed answer. Metabolism. Digestive organs. Questions with “yes” or “no” answers. Chemical transformations. Plastic exchange. Energy exchange. Text with errors. Preparing students for assignments open type. Definition. Test tasks.

"Metabolism" - Protein. Metabolism and energy (metabolism). A protein consisting of 500 monomers. One of the gene chains carrying the protein program must consist of 500 triplets. Solution. What primary structure will the protein have? Reactions of assimilation and dissimilation. Broadcast. 2 metabolic processes. Determine the length of the corresponding gene. Genetic code. Properties of the genetic code. DNA. Autotrophs. Molecular weight of one amino acid.

“Energy metabolism” - Repetition. Biological oxidation and combustion. Energy released in glycolysis reactions. The fate of the PVK. Enzymes of the oxygen-free stage of energy exchange. Lactic acid. Preparatory stage. The process of energy metabolism. Lactic acid fermentation. Glycolysis. Combustion. Energy exchange. Oxidation of substance A.

Description of the presentation by individual slides:

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Carbohydrates. Functions of carbohydrates. the role of the main source of energy in the human body. Prepared by student of group PNK-11 Semyonova Victoria

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Carbohydrates - organic compounds, consisting of carbon, hydrogen and oxygen, with hydrogen and oxygen in the ratio (2:1) as in water, hence the name.

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Carbohydrates are substances of the composition CmH2nOp, which are of paramount biochemical importance, are widespread in living nature and play an important role in human life. Carbohydrates are part of the cells and tissues of all plant and animal organisms and, by weight, make up the bulk of organic matter on the ground. Carbohydrates account for about 80% of the dry matter in plants and about 20% in animals. Plants synthesize carbohydrates from inorganic compounds - carbon dioxide and water (CO2 and H2O).

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Carbohydrate reserves in the human body Carbohydrate reserves in the form of glycogen in the human body are approximately 500 g. The bulk of it (2/3) is located in the muscles, 1/3 in the liver. Between meals, glycogen breaks down into glucose molecules, which mitigates fluctuations in blood sugar levels. Without carbohydrates, glycogen stores are depleted in about 12-18 hours. In this case, the mechanism for the formation of carbohydrates from intermediate products of protein metabolism is activated. This is due to the fact that carbohydrates are vital for the formation of energy in tissues, especially the brain. Brain cells obtain energy primarily through the oxidation of glucose.

6 slide

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Functions in the human body The first thing to note is the energy role of carbohydrates. They cover approximately 60% of the body's total calorie needs. In this case, the resulting energy is either immediately spent on heat generation, or accumulated in the form of ATP molecules, which can later be used for the needs of the body. As a result of the oxidation of 1 g of carbohydrates, 17 kJ of energy (4.1 kcal) is released; The plastic role of carbohydrates is no less important. They are spent on the synthesis of nucleic acids, nucleotides, elements cell membrane, polysaccharides, enzymes, ADP and ATP, as well as complex proteins; The storage function of carbohydrates is very important. nutrients. The main depot of carbohydrates is the liver, where they are stored in the form of glycogen. In addition, small “storages” of glycogen in the muscles are also of some importance. Moreover, the more developed the latter, the greater the “energy capacity” of the body;

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Functions in the human body The specific function of carbohydrates seems quite interesting. It lies in the fact that certain carbohydrates can prevent tumor growth, and can also determine a person’s blood type; The protective role of these substances is also important. Complex carbohydrates are an essential component of many elements immune system, and mucopolysaccharides provide protection to the mucous membranes of the body from the penetration of microorganisms and mechanical damage; Great value has a regulatory function of carbohydrates. It lies in the fact that fiber ensures the normal functioning of the intestines, without itself being broken down in the gastrointestinal tract;

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CLASSIFICATION OF CARBOHYDRATES MONOSACHARIDES - carbohydrates that are not hydrolyzed. Depending on the number of carbon atoms, they are divided into trioses, tetroses, pentoses, and hexoses. DISACCHARIDES are carbohydrates that are hydrolyzed to form two molecules of monosaccharides. POLYSACCHARIDES - high molecular weight compounds - carbohydrates that are hydrolyzed to form many monosaccharide molecules.

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Glucose is one of the key metabolic products that provide living cells with energy (in the processes of respiration, fermentation, glycolysis); Serves as the initial product of the biosynthesis of many substances; In humans and animals, a constant level of glucose in the blood is maintained through the synthesis and breakdown of glycogen; In the human body, glucose is found in the muscles, in the blood and in small quantities in all cells.

Structure and classification of carbohydrates. Physico- Chemical properties.

Functions of carbohydrates in organism.

External exchange. The importance of carbohydrate components of food. Consumption standards. Amylases, disaccharidases. Absorption of hydrolysis products.

Phosphorylation and dephosphorylation of sugars. Meaning.

Interconversions of sugars. Epimerases, isomerases, UDP transferases. Glucose is the main carbohydrate in intermediate metabolism.

Transport of glucose into cells. GLUTES. Insulin-dependent and independent tissues.

Intermediate glucose metabolism. The relationship between catabolic and anabolic processes. Consumption of glucose in various metabolic processes.

Glycolysis. Definition. Meaning. Two stages. Key enzymes. Final products. Regulation.

Features of glycolysis in different tissues. Shunts.Pentose phosphate pathway metabolism. Rappoport shunt in erythrocytes.

Aerobic glucose metabolism. Pyruvate oxidation . Multienzyme complex. Mechanism of reactions. Regulation.

Tricarboxylic acid cycle– general stage of catabolism of amino acids, glucose and fatty acids. Meaning. Mechanism of reactions. Localization. Energy output.

Carbohydrates and carbohydrate metabolism.

Glycogen. Structure. Meaning.

Glycogen synthesis. Enzymes.

Glycogen mobilization. Phosphorolysis. Enzymes. Relationship between glycogenolysis and glycolysis.

Regulation of glycogen synthesis and breakdown processes.

Regulation of glycogen breakdown in the liver, muscles (at rest and muscle load).

Gluconeogenesis is an adaptive metabolic pathway for glucose synthesis. Enzymes. Regulation. Relationship with glycolysis. Idle cycles.

Glucose homeostasis. Key points of regulation.

Carbohydrates and carbohydrate metabolism

Classification of carbohydrates(mono-, disaccharides, oligosaccharides, polysaccharides - neutral and acidic);

Acetylated, aminated, sulfo- and phospho-sugar derivatives;

Physico-chemical properties of carbohydrates . Solubility. Aldoses and ketoses.

Proteoglycan aggregate from epiphyseal cartilage

Functions of carbohydrates

1. Energy (1g carbohydrates – 4.1 kcal) – glucose.

Advantage of carbohydrate oxidation under anaerobic conditions. The role of glucose in the oxidation of carbon residues of amino acids and lipids.

2. Plastic - ribose and NADPH are formed in the pentose phosphate pathway of glucose oxidation.

3. Structural – hyaluronic acid, keratan sulfate,

dermatan sulfate, chondroethin sulfate.

4. Storage – glycogen.

5. Binding of water, cations – acid heteropolysaccharidesintercellular matrix. Formation of gels, viscous colloids ( articular surfaces lining surfaces genitourinary tract and gastrointestinal tract).

6. Regulatory (heparin - dependent drug lipase);

7. Anticoagulant– heparin, dermatan sulfate.

Biological role of carbohydrates

Classification of carbohydrates

Monosaccharides

OLIGOSACHARIDES

Sucrose (cane or beet sugar) –

Maltose (fruit sugar)

Lactose (milk sugar)

POLYSACCHARIDES

Glycogen – animal starch

Heteropolysaccharides (heteroglycans)

Chondroitin sulfates –

The norm of carbohydrates in the diet

The absorption of oligo- and polysaccharides occurs during their hydrolytic breakdown into monosaccharides. Glycosidases attack 1-4 and 1-6 glycosidic bonds. About

WALL DIGESTION

Cellulose in the human body

Only monosaccharides are absorbed in the intestine

2) glucose transfer is also possible against a concentration gradient.

MAIN SOURCES OF GLUCOSE

MAIN WAYS OF USING GLUCOSE

SOURCES AND WAYS OF GLUCOSE CONSUMPTION

GLYCOGENOLYSIS

GLYCOLYSIS

Anaerobic GLYCOLYSIS

AEROBIC AND ANAEROBIC DECOMPOSITION OF GLUCOSE

ENERGY BALANCE OF AEROBIC OXIDATION OF GLUCOSE

Gluconeogenesis

Places of entry of substrates (precursors) for gluconeogenesis

RELATIONSHIP OF GLYCOLYSIS AND GLUCONEOGENESIS

MEASLES CYCLE

Glucose-alanine cycle

CHARACTERISTICS OF THE PENTOSOPHOSPHATE PATHWAY

FUNCTIONS OF THE PENTOSOPHOSPHATE PATHWAY

Oxidative decarboxylation of pyruvate -

Tricarboxylic acid cycle

Role of the TTC

Disorders of carbohydrate metabolism with:

Carbohydrates and carbohydrate metabolism.

Carbohydrates and carbohydrate metabolism

Proteoglycan aggregate from epiphyseal cartilage

Functions of carbohydrates

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