Exchange of materials. Intensity of metabolic processes in the body. Temperature homeostasis
Metabolism of proteins
Physiological meaning of proteins
1. All enzymes are protein.
2. All moving in organism provide with cooperation of contractive proteins.
3. Proteins have plastic and energy function.
4. Proteins enter to hormones composition.
5. Proteins enter to the cells’ membrane structure.
Transformation of proteins in human organism
Protein enter to our organism with food.
Then they pass through digestive tract, absorbed in blood in amino acids case.
Some quantity goes to the cells of different tissues, other to liver.
In liver from it synthesis enzymes and protein of blood plasma. It is per amine processes; by way of desaminate formed ammonium (NH3) and ketonic acids. From ammonium formed urea and then urine acid. It and proteins of tissues formed blood rest nitrogen, which go to kidney and excreted in case of urine nitrogen. Ketonic acids oxide and from them synthesize glycogen and fat acids.
Nitrogen balance
Iorm quantity of nitrogen which come to organism (with proteins) must be equal quantity of nitrogen, which go out from organism (with urine, feces and perspiration.
Nitrogen balance is the ratio of nitrogen quantity, which enters in organism with food and distinguished by kidney, digestive tract, glands. In protein is 16 % of nitrogen. One gram of nitrogen is present in
Minimum of proteins, optimum of proteins, biological value of proteins
Minimum of proteins is minimal quantity of protein in which save nitrogen balance; It daily quantity is near
Regulation of proteins metabolism
Central mechanism of regulation act on hypothalamus. It activates pituitary gland, they produce growth hormone; activate thyroid glands and adrenal glands. Hypothalamus has parasympathetic and sympathetic centers. Parasympathetic influences, growth hormone, insulin, thyroid hormones, glucocorticoids (in liver) have anabolic effect. Sympathetic influences, glucocorticoids (in muscles, lymph tissues) have katabolic effect.
Metabolism of fats
Physiological meaning of fats
1. Fat enter to the cells’ membrane structure.
2. Fat necessary to the structure of steroid hormones.
3. Fats is a spring of energy.
Transformation of fats in human organism Fats enter in our organism with food (threeglycerides). It absorbed in case of fat acids with short and long chains and glycerin from digestive tract. Fat acids with short chain and glycerin go in blood, then to fat depo, heart, liver. Fat acids with long chain go into mucus shell of intestine, where threeglycerides absorbed in chilimicrones case. Then they go to lymph and blood.
Regulation of fats metabolism
Central mechanism of regulation act on hypothalamus. It is activate hypophysis, which produce growth hormone; activate thyroid glands and adrenal glands. Hypothalamus has parasympathetic and sympathetic centers. Parasympathetic influences, insulin, glucocorticoids have anabolic effect. Sympathetic influences, thyroid hormones, glukagon, epinephrine, growth hormone have katabolic effect.
Metabolism of carbohydrates
Physiological meaning of carbohydrates
1. Carbohydrates are a main spring of energy.
2. Carbohydrates are the part of some enzymes.
Transformation of carbohydrates in human organism
Carbohydrates enter in our organism with food. It absorbed in case of glucose from digestive tract. Glucose goes in blood, then in brain, liver and muscles. Depo of glycogen are in liver and muscles in rest condition. In working muscles they divide to lactic acid, water and CO2.
Regulation of carbohydrates metabolism
Central mechanism of regulation act on hypothalamus. It is activate hypophysis, which produce growth hormone; activate thyroid glands and adrenal glands. Hypothalamus has parasympathetic and sympathetic centers. Parasympathetic influences, insulin has anabolic effect. Sympathetic influences, growth hormone, glucocorticoids, thyroid hormones, glukagon, epinephrine have katabolic effect.
Vitamins
Vitamin C take place in oxygen-reducing metabolic processes in organism, develop of kolagen of blood vessels’ wall, increase antitoxic function of liver.
Vitamin B1 takes place in metabolism of carbohydrates, protein and fats, secure normal growth, increases motor and secretor function of stomach, normalized heart activity.
Vitamin B2 takes place in growth and development of fetus and child.
Vitamin B6 takes place in protein metabolism, fat metabolism, influence on development of blood component.
Vitamin B12 necessary for hemopoiesis.
Vitamin A secure normal growth and development, take place in vision pigment synthesis, secure adaptation of eyes to light.
Vitamin D regulate metabolism of calcium and phosphorus.
Vitamin E has antitoxic effect on cells lipids.
Vitamin K secures normal hemostasis processes.
Methods of studying organisms’ energy expenditure
Method of direct calorimetry
Method of indirect calorimetry with the complete gas analyses
Method of indirect calorimetry with the incomplete gas analyses
Meaning of “respiratory quotient” (RQ), “caloric equivalent of oxygen”
The respiratory quotient is the ratio of the volume of CO2 produced to the volume of O2 consumed per unit of time. The RQ of carbohydrate is 1,00;
of fat is about 0,7;
of protein is about 0,8.
Caloric equivalent of oxygen is a quantity of heat, which are take out after consuming of one liter of oxygen.
Factors which influence on basal metabolic rate
muscular excercises
recent ingestion of food
environmental temperature
height
Weight
Sex
Age
emotional state
body temperature
pregnancy or menstruating
circulating level of thyroid hormones
circulating epinephrine and norepinephrine levels
condition of inner organs.
Characteristic of professional group
I professional group – the person, whose work don’t connect with the spend on physical work or don’t need essential physical effort. Common daily expenditure of energy is 2200-3300 kcal.
II professional group – Worker of mechanical work and sphere of service, which work does not need a big physical effort. Common daily expenditure of energy is 2350-3500 kcal.
III professional group – Worker of mechanical work and sphere of service, which work connects with the considerable physical efforts. Common daily expenditure of energy is 2500-3700 kcal.
IV professional group – Worker of do not mechanical work or partly mechanical work with a big and middle heavily. Common daily expenditure of energy is 2900-4200 kcal.
V professional group – Worker of do not mechanical work with a big heavility. Common daily expenditure of energy is more than 4200 kcal.
Physiological meaning of proteins 1. All enzymes are protein. 2. All moving in organism provide with cooperation of contractive proteins. 3. Proteins have plastic and energy function. 4. Proteins enter to hormones composition. 5. Proteins enter to the cells’ membrane structure.
Transformation of proteins in human organism
Protein enter to our organism with food. Then they pass through digestive tract, absorbed in blood in amino acids case. Some quantity goes to the cells of different tissues, other to liver. In liver from it synthesis enzymes and protein of blood plasma. It is pereamine processes; by way of desaminate formed ammonium (NH3) and ketonic acids. From ammonium formed urea and then urine acid. It and proteins of tissues formed blood rest nitrogen, which go to kidney and excreted in case of urine nitrogen. Ketonic acids oxide and from them synthesize glycogen and fat acids.
Nitrogen balance
Iorm quantity of nitrogen which come to organism (with proteins) must be equal quantity of nitrogen, which go out from organism (with urine, feces and perspiration. Nitrogen balance is the ratio of nitrogen quantity, which enters in organism with food and distinguished by kidney, digestive tract, glands. In protein is 16 % of nitrogen. One gram of nitrogen is present in
Minimum of proteins, optimum of proteins, biological value of proteins Minimum of proteins is minimal quantity of protein in which save nitrogen balance; It daily quantity is near
Regulation of proteins metabolism
Central mechanism of regulation act on hypothalamus. It activates pituitary gland, they produce growth hormone; activate thyroid glands and adrenal glands. Hypothalamus has parasympathetic and sympathetic centers. Parasympathetic influences, growth hormone, insulin, thyroid hormones, glucocorticoids (in liver) have anabolic effect. Sympathetic influences, glucocorticoids (in muscles, lymph tissues) have katabolic effect.
Metabolism of fats
Physiological meaning of fats 1. Fat enter to the cells’ membrane structure.
2. Fat necessary to the structure of steroid hormones. 3. Fats is a spring of energy.
Transformation of fats in human organism
Fats enter in our organism with food (threeglycerides). It absorbed in case of fat acids with short and long chains and glycerin from digestive tract. Fat acids with short chain and glycerin go in blood, then to fat depo, heart, liver. Fat acids with long chain go into mucus shell of intestine, where threeglycerides absorbed in chilimicrones case. Then they go to lymph and blood.
Regulation of fats metabolism
Central mechanism of regulation act on hypothalamus. It is activate hypophysis, which produce growth hormone; activate thyroid glands and adrenal glands. Hypothalamus has parasympathetic and sympathetic centers. Parasympathetic influences, insulin, glucocorticoids have anabolic effect. Sympathetic influences, thyroid hormones, glukagon, epinephrine, growth hormone have katabolic effect.
Metabolism of carbohydratesPhysiological meaning of carbohydrates
1. Carbohydrates are a main spring of energy. 2. Carbohydrates are the part of some enzymes.Transformation of carbohydrates in human organism
Carbohydrates enter in our organism with food. It absorbed in case of glucose from digestive tract. Glucose goes in blood, then in brain, liver and muscles. Depo of glycogen are in liver and muscles in rest condition. In working muscles they divide to lactic acid, water and CO2.
Regulation of carbohydrates metabolism
Central mechanism of regulation act on hypothalamus. It is activate hypophysis, which produce growth hormone; activate thyroid glands and adrenal glands. Hypothalamus has parasympathetic and sympathetic centers. Parasympathetic influences, insulin has anabolic effect. Sympathetic influences, growth hormone, glucocorticoids, thyroid hormones, glukagon, epinephrine have katabolic effect.
Vitamins Physiological meaning of water-solution vitamins
Vitamin C take place in oxygen-reducing metabolic processes in organism, develop of kolagen of blood vessels’ wall, increase antitoxic function of liver. Vitamin B1 takes place in metabolism of carbohydrates, protein and fats, secure normal growth, increases motor and secretor function of stomach, normalized heart activity. Vitamin B2 takes place in growth and development of fetus and child. Vitamin B6 takes place in protein metabolism, fat metabolism, influence on development of blood component. Vitamin B12 necessary for hemopoiesis.
Physiological action of fat-solution vitamins
Vitamin A secure normal growth and development, take place in vision pigment synthesis, secure adaptation of eyes to light. Vitamin D regulate metabolism of calcium and phosphorus. Vitamin E has antitoxic effect on cells lipids. Vitamin K secures normal hemostasis processes.
Bioenergetics
Overview
Nutrients
fuel for energy supply
energy storages
Energy Systems
Energy transfer
High energy phosphates
ATP
ATP utilization
other high energy phosphates
ways to produce ATP
Electron transfer
reduction equivalents
Energy supply for the body
Nutrients: Fuels for the body
There are different nutrients used to produce energy for the metabolism
Carbohydrates: 16 kJ/g
Fat: 37 kJ/g
Protein: 17 kJ/g
Carbohydrates (CHO) can be metabolised under aerobic and anaerobic conditions
Proteins and fat require oxygen to be metabolised
Energy supply for the body
Storing energy
The body gains ‘energy sources’ by the all day dietary uptake
…but the body even stores energy for times of starvation
Fat 79%
Protein 20%
Carbohydrates 1%
most energy is stored as fat
Most of the energy used comes from CHO
Energy supply for the body
Catabolic and anabolic metabolism
Catabolic metabolism is the break down or oxidation of nutrients
it releases energy
it produces intermediates that are useful for the metabolism
Anabolic metabolism produces or synthesises new components or substances i.e. enzymes, fat, hormones…
This consumes energy
It requires different precursors
Energy of the catabolic metabolism is used for the anabolic metabolism
Synthesized end products
Catabolic metabolism is the break down or oxidation of nutrients
it releases energy
it produces intermediates that are useful for the metabolism
Anabolic metabolism produces or synthesises new components or substances i.e. enzymes, fat, hormones…
This consumes energy
It requires different precursors
Energy of the catabolic metabolism is used for the anabolic metabolism
Synthesized end products CHO, fats, proteins + O2
Anabolism Catabolism
Precursors H2O + CO2
Energy systems
Main systems are:
Glycolysis
TCA- or Krebs-Cycle
Electron transport chain and oxidative phosphorylation
The systems are not isolated
They work together and parallel to each other
Energy systems
The different energy systems of the human body are used regarding to different energetic demands
The choice of the energy system is influence by the
Supply velocity
availability
oxygen supply
Energy transfer
Metabolic energy is generated by oxidizing different nutrients
Principally oxidation is similar to a combustion
C6H1206 + 6O2 à 6 CO2 + 6 H2O
This formula describes the over all reaction when the body ‘burns’ Glucose by aerobic glycolysis
The same formula can be used to describe the reaction when wood is burned in a fire
Energy transfer
In the cell the energy is released in many single portions
Controlled enzymatic reactions are used to convert and transfer the chemical energy of the oxidation to make it utilizable for the metabolism
High energy phosphates
Adenosine triphosphate
Energy of food oxidation is used to produce ATP that is used as a universal cellular energy ‘currency
High energy phosphates
ATP – Hydroysation
In the metabolism transfer of phosphate residues or hydrolysation of phosphate bonds is used to store, transfer and utilize chemical energy
ATPase
ATP ADP + Pi + energy
work
mechanical synthesis
transport
High energy phosphates
Myokinase reaction
ADP is still a ‘high energy phosphate’
It has…
less energy than ATP
but more than AMP
This fact is used by tissues with a high energy turnover like skeletal muscle
2 ADP ATP + AMP
From 2 ADP which cannot be used by the muscle (myosin ATPase)
1 ATP is produced that can be used!
Other high energetic phosphates
Beside ATP the other nucleotide triphosphates are used:
GTP, UTP, CTP
there are other high energy phosphates:
intermediates of the Glycolysis
1,3-diphosphoglycerate
phosphoenol pyruvate
Creatine-Phosphate as energy reservoir in the skeletal muscle (phosphagen system
Creatine phosphate: the phosphagen system
The working skelketal muscle has a very high ATP turn over
The phosphagen or creatine kinase system enables the fast regeneration of ATP from Creatine phosphate and ADP in situations with an exceeding ATP demand
CrP + ADP Cr + ATP
Under resting condition Creatine phosphate is regenerated by the reverse reaction
Production of ATP
There are two different ways to produce ATP from ADP and Pi
Substrate level phosphorylation
energy of the oxidation is directly converted by transferring a phosphate (Pi) from an intermediate (Phosphoenol pyruvate) to ADP
(Glycolysis and Citric acid cycle)
Oxidative phosphorylation
Energy of oxidation is used to produce reduction equivalents these are oxidized in the mitochondria by oxygen
This energy is indirectly used to produce ATP
Electron transfer
Oxidation/Reduction
Reduction equivalents are the ‘second energy currency’ of the cell
They are used to transport electrons (e-) from the nutrient to the final oxidizing agents (in human O2)
The most important reduction equivalents are
NAD+
FAD
NADP+
The electron from NADPH + H+ reduction are not used to produce ATP but for the anabolic metabolism
Carbohydrates, fat or proteins are used to generate metabolic energy
Different systems work together to guarantee sufficient energy supply under different physiological conditions
Nutrients are oxidized and the energy is used to produce ATP and or other high energy phosphates
ATP can be produced by substrate level phosphorylation or by oxidative phosphorylation
Electron transport especially to the electron transport chain is important for energy utilisation
1. characteristic of physiological value of maiutritive products
a) Milk and sour milk products
Milk is one of the most valuable products of feed. It has all necessary substances for normal growth and development of organism. Milk has near 100 different components, and near 20 amino acids. Milk fat has a lot of high insatiable fat acids, vitamins. It is in emulsification case. Milk has cholesterol and lecetin, which are in good balance condition. In milk present milk sugar – lactose, which help mastering of calcium. Milk has different mineral substances, the optimal concentration of calcium and phosphorus. In milk present vitamins A, D, B2, B6. Sour milk products are cream, sour cream, cheese, yoghurt. It is mastering better than milk (after one hour mastering 91 % of sour milk products and only 32 % of milk.
b) Meat and meat products
In food use meet of cattle, live-stock, pigs, rabbits, birds, meat products. It is the main source of proteins, it has fats, extractive and mineral substances, vitamins. Boiled meat has a better effect on digestive organs than grilled and stew. Veal, beef, rabbit, chicken, turkey digestive better than meat from pig, goose, duck.
c) Grain products (grain, bread)
Cereals make from grain-crops. It has a lot of carbohydrates, some quantity of proteins, and small quantity of fats. Cereals has phosphor and calcium, iron, magnesium, vitamins of B group. There are rise, oats, millet, buckwheat, barley cereals. Bread has 40-50 % of carbohydrates, 5-8 % of protein. In bread are present proteins. Brown bread has more influence on stomach secretion than white bread; fresh bread has more influence on stomach secretion than stale bread and piece of dried bread..
d) Vegetables, fruits and small fruits (berries)
Vegetables is the main source of carbohydrates in a case of sugar, starch, pectin. In carrot is present near 6 % of carbohydrates, in beetroot present near 8 % of carbohydrates. There is 75-95 % of water in vegetables. Vitamins and mineral substances are present in a big quantity in vegetables too. Vegetables stimulated stomach secretion, motor function of digestive tract, production of bile. It is help to mastering proteins, fats, carbohydrates and vitamins. Fruits and small fruits (berries) have a lot of vitamins, mineral salts. There are near 85 % of water in fruits and small fruits (berries). It has organic substances, pectin.
e) Acquiring of food
Mastering of food is a ratio between quantity of nutrition which are master by organism to common quantity of food which we eat. Near 95 % of animal products are mastering, near 80 % of plant products are mastering, near 82-90 % of mix products are mastering. Mastering of protein from animal products is 97 %, from plant is 85 %, and from mix food is 92 %. Food must be good chew; it must be good surrounding condition for eating.
f) Isodynamic of nutritious substances, their caloric coefficient
We eat protein, carbohydrates, fats. Products of it hydrolyzing go into energy of organism. Amino acids, fat acids, monosaccharides connect in energy metabolism. It all has own energy value. Caloric coefficient of fat is 9,0 kcal/g, protein is 4,0 kcal/g, carbohydrates is 3,75 kcal/g. But we must remember, that we must eat fats, protein, carbohydrates, because in this case, when we eat only one products, may be only energy substitution and our organism need all nutrition for vital activity.
2. Principles of putting of nutritive rations
a) Accordance of calorific value of day ration to energy loss
Caloricity of daily ration must be equal to energy spend of organism. Person of I professional group need 40 kcal/kg of weight; person of II professional group need 43 kcal/kg of weight; person of III professional group need 46 kcal/kg of weight; person of IV professional group need 53 kcal/kg of weight; person of V professional group need 61 kcal/kg of weight.
b) Regime of nutrition
If we eat 4 times per day: breakfast must have 25-30 % of daily caloricity, lunch (after dinner eating) or before supper eating must have 10-15 %, dinner must have 40-45 % daily caloricity, supper must have 20 % of daily caloricity. If we eat 3 times per day: breakfast must have 30 % of daily caloricity, dinner must have 45-50 % daily caloricity, and supper must have 20-25 % of daily caloricity. Time between breakfast and dinner must be to 5-6 hours; time between dinner and supper must be 6-7 hours. Optimal duration between eating is 4-5 hours, at night is 8-10 hours.
c) Completeness and coordinateness of ration
Our food must have optimal ratio of protein, fats, carbohydrates, vitamins, mineral substances. Optimal norm of protein is 1,5 g/kg of weigh per day. Protein must give 14-15 % of daily caloricity. Optimal norm of fat is 1,5 g/kg of weigh per day. Fat must give 28-30 % of daily caloricity. Average norm of carbohydrates is 400-
d) Individual-physiologic peculiarities of organism into consideration Breakfast must begin from salad, which activate digestive secretion. Then must be food with the main source of energy and nutrition’s, on the end must be tonic drink (tea, coffee, cacao). Dinner must begin from salad (when you have less of appetite). We must remember than dinner does not begin from food, which decrease stomach secretion. Supper must consist food which good digest (fish, milk, and eggs), drinks, which do not stimulate central nerve system.
