Fats dissolve well in water. Water-insoluble fats. Energy function. They are the main structural component of biological membranes. Completely soluble in ethyl ether
Lipids.
organic substances.
Fats and lipoids also perform a building function; they are part of cell membranes. Due to poor thermal conductivity, fat is capable of a protective function. In some animals (seals, whales), it is deposited in the subcutaneous adipose tissue, forming a layer up to 1 m thick. The formation of some lipoids precedes the synthesis of a number of hormones. Consequently, these substances also have the function of regulating metabolic processes.
Fats and lipoids.
Double-stranded RNAs differ in structure. Double-stranded RNAs are the keepers of genetic information in a number of viruses, i.e. perform the functions of chromosomes. Single-stranded RNAs carry out the transfer of information about the structure of proteins from the chromosome to the site of their synthesis and participate in protein synthesis.
There are several types of single-stranded RNA. Their names are due to their function or location in the cell. Most of the cytoplasmic RNA (up to 80-90%) is ribosomal RNA (rRNA) contained in ribosomes. rRNA molecules are relatively small and consist of an average of 10 nucleotides. Another type of RNA (mRNA) that carries information about the sequence of amino acids in proteins to be synthesized to ribosomes. The size of these RNAs depends on the length of the DNA segment from which they were synthesized. Transfer RNAs perform several functions. They deliver amino acids to the site of protein synthesis, "recognize" (according to the principle of complementarity) the triplet and RNA corresponding to the transferred amino acid, and carry out the exact orientation of the amino acid on the ribosome.
Fats are compounds of fatty macromolecular acids and the trihydric alcohol glycerol. Fats do not dissolve in water - they are hydrophobic. There are always other complex hydrophobic fat-like substances in the cell, called lipoids.
One of the main functions of fats is energy. The fat content in the cell ranges from 5-15% of the dry matter mass. In the cells of living tissue, the amount of fat increases to 90%. Accumulating in the cells of adipose tissue of animals, in the seeds and fruits of plants, fat serves as a reserve source of energy.
They make up 20 - 30% of the composition of the cell. They can be simple (amino acids, glucose, fatty acids) and complex (proteins, polysaccharides, IC, lipids).
NUCLEIC ACIDS (polynucleotides), biopolymers that store and transfer genetic. information in all living organisms, as well as those involved in the biosynthesis of proteins. The primary structure of nucleic acids is a sequence of nucleotide residues. The latter in the nucleic acid molecule form unbranched chains. Depending on the nature of the carbohydrate residue in the nucleotide (D-deoxyribose or D-ribose), nucleic acids are divided respectively. on deoxyribonucleic (DNA) and ribonucleic (RNA) to-you.
DNA is the largest biopolymer containing up to 108-109 monomers - deoxyribonucleotides, which contain sugar - deoxyribose. DNA contains 4 types of deoxyribonucleotides: adenine - A, thymidine - T, guanine - G, cytosine - C.
"The use of fats" - Perfumery. Animal food. Fats. The sweet is better than the fat. Soap. How much and what kind of fat a person needs. Chocolate. The use of fats. Candles. Glycerol. Propolis. Dye.
"Properties and uses of fats" - Margarine. 600 different types of fats have been identified. Practical application in life. A mixture of esters. Charles Wurtz. Determination of unsaturation of fats. Synthesis of fats. Fats. Discoloration of bromine water. alkalis. cocoa beans. Mixture. Preparation of oil paints. Fat hydrolysis reaction equation. Inedible fat.
"Essential oils" - Phenols. Greek warriors treated wounds with ointments made from myrrh. Pinen. Ethers. Oxygen is the main element of essential oil. Stress bath. Ketones relieve congestion, accelerate the circulation of mucus. The aroma is cold, fresh, bitter. What is aromatherapy? The healing properties of mint were used 3000 years ago in ancient Egypt.
"Dietary fats" - Dietary fats. Characterize one sample of vegetable oil. Orientation. pre-prepared questions. Solve the crossword puzzle. Mustard oil. List the largest number of edible fats. On the rules for the purchase and storage of oils. The authenticity of the goods. The content of the work. Chess. Stages of merchandising all-around.
"Chemistry of Fats Grade 10" - Fats. Conclusion: Strong acids displace weak acids from salt solutions. sodium stearate. carb properties. to-t, similar to mineral, on the example of acetic acid. Complex ethers. Laboratory experiment No. 1 "The action of strong acids on soap" L. Alkaline hydrolysis of fats. Laboratory experiment No. 2 "The action of soap in hard water."
"Esters and Fats" - Acetic acid. To shift the equilibrium to the right, it is necessary to remove water or ether. Fats are widely distributed in nature and by origin are divided into animal and vegetable. Esters are very common in nature. Esters with a pleasant smell are used in perfumery and the food industry.
There are 13 presentations in total in the topic
Answer from Elena Kazakova[guru]
They are hydrophobic.
Hydrophobic molecules surrounded by water tend to get closer, because in this case the structure of water, stabilized by hydrogen bonds, is disturbed to the least extent. In this case, the total surface area wetted by water is the smallest.
Answer from Yustas[guru]
Because fats are hydrophobes for the most part. After all, small parts of molecules interact with water with hydrophobes, so, accordingly, they partially dissolve but not completely, but poor interaction due to the small angle of interaction between water and a fat molecule)
Answer from Aka Diesel[guru]
Because nope!
Answer from Krosh[newbie]
Fat is lighter than water!
Answer from Serserkov[guru]
Water is a polar solvent, it dissolves substances with a polar molecular structure. Fats are non-polar. hence their hydrophobicity. In fact, they dissolve, but very poorly.
Answer from Elena Yashina[active]
The water is human, the fat is God's. "Give it to God" (Pentateuch of Moses, it seems Leviticus). Water is a symbol of repentance, John the Baptist, the best of men. Oil, oil symbol of God. The interaction of God and man, Under the influence of the sun, fire (the Word of God is fire), water breaks up rises to heaven, turns into clouds, again into water and falls to the ground either in the form of blessed rain, watering the dry land, or irrigating the fertile land again and again , or in the form of more formidable rainfall, punishing the wicked if necessary. Water above, in the sky, and water below on earth, in the earth. Just the other day, I had a constellation in my mind: according to the Old Testament, when God's people walked together according to the action of God through Moses, the water parted, and the sea, and already before entering the Promised Land, the river. They went dry. According to the New Testament in John the Baptist, through repentance before God, we promise God a good conscience before God in every person. That is, the water remains around me, then suddenly the Lord comes (Malachi 3.1), and then I in Jesus (God in me, I and God are one) already walk on the water: that is, those who think not like God already according to me, pagans (goyim, peoples not of God), who do not have the truth of God, which means the power of God. And in Christ Jesus, indeed, God's people are united into one Body of the Lord, as someone before me answered, oil is united into one. Wrong reason can no longer prevent me from doing right. That is, "the law did not bring anything to perfection, but a better hope is being introduced." The water cycle in nature prolongs life on earth, giving it new colors of the rainbow. After all, with a rainbow, God confirmed his promise that there would be no more global flood (Genesis 9 chapter). Even in the Old Testament, the coming of Jesus was promised. And now we live a new life. "Behold, I make all things new", "Whoever is in Christ, he is a new creation (creation)."
All the main components of nutrition, our body has learned to store in reserve- Yes, just in case. He stores sugar in the liver, proteins in the stomach, but for fats, a place under the skin is chosen. Want to lose weight? We'll have to go to war on our own body! To win, you must fight skillfully. This article will teach you a lot!
Fats… What is it? Where do they come from? Why are they deposited under the skin? And in general, why are they needed? Maybe they shouldn't be eaten? It sounds reasonable, because we have so many problems with the figure from fat!
The first stage of fat transformation: food intakeWith this, everything is clear: we sat down at the table and loaded food into ourselves. So, the “processing” of fats by the body begins already in your mouth, when the salivary glands secrete saliva saturated with special digestive enzymes. Further, it would seem that the stomach should be connected to this work. Oddly enough, fats are not his profile. So he simply passes them through himself and sends them further into the intestines. And here the fats will be digested and absorbed into the blood. By the way, why do we need these same fats? And wouldn't it be better not to eat them at all?
Let's give a word to science- Fats are the energy "fuel" of the body
- Fats are vital as a building block of skin, hair, nails…
- Fats are "raw materials" for the production of hormones.
Fats are unlike carbohydrates and proteins in that they do not dissolve in water. It turns out that the water needs to be replaced with something, right? Especially for the sake of fats, our body secretes bile. Complete dissolution of fats and she is "too tough". But she knows how to "crush" fats into microscopic drops - triglycerides. And the intestines can cope with them.
Word to scienceA triglyceride is three fatty acid molecules "glued" to a glycerol molecule. In the intestines, some of the triglycerides combine with proteins and begin their journey through the body with them.
The third stage of fat transformation: the journey
Yes, triglycerides do not know how to travel on their own. They definitely need a vehicle called "lipoprotein". Lipoproteins are different, and each has its own task.
- Chylomicrons are formed in the intestines from fats and carrier proteins. Their task is to transfer the fat received with food from the intestines to tissues and cells.
- Very high density lipoproteins also transport fat to different tissues and cells, but take it exclusively in the liver.
- Low-density lipoproteins also deliver fats from the liver to body tissues. What is the difference? And the fact that along the way, these lipoproteins "grab" cholesterol from the intestines and carry it throughout the body. So if somewhere in the vessels you have formed cholesterol clots, threatening cardiovascular disease, then here is the culprit - low density lipoproteins.
- High density lipoproteins - have one function - just the opposite. These lipoproteins, on the contrary, collect cholesterol throughout the body and take it to the liver for destruction. Very useful connections.
These details help to understand that eating fatty foods does not automatically increase the level of cholesterol in the body. A risky situation occurs if the body has too many low-density lipoproteins (which help to store cholesterol) and not enough high-density lipoproteins (those that are responsible for removing cholesterol). And this is a purely genetic factor. There is also an arithmetic factor. This is when you eat so much of this very cholesterol that no lipoproteins are enough to remove it. And here is another find of science. It has been established that cholesterol is especially abundant in animal fats. But vegetable fats in this sense are not an example more useful. It would seem that it is necessary to eat less animal fats, and more vegetable fats. No matter how! The beneficial effect of vegetable fats will affect only in one case: if you completely replace animals with them.
If the body has received more than it needs, then an enzyme called lipase comes into play. Its task is to hide all the excess inside the fat cells.
Word to scienceLipase is a kind of key that opens the doors of fat cells towards fats. Fat cells can let in a lot of fat inside and swell up like a balloon. This just answers that you are getting fat. If one fat cell or even a hundred increases, then no one will notice it. However, if you eat too much fat, the myriad fat cells under the skin will swell at once. And you can't hide it from your eyes. Moreover, lipase can give a command for the reproduction of fat cells. And also to the eyeballs will fill them with fat. Worst of all, fat cells cannot be destroyed. When you undertake to lose weight, lipase "opens" fat cells and releases fat out, well, then it "burns out" during exercise. You look in the mirror: not a drop of fat! Meanwhile, all the fat cells are in place, but only look like punctured balloons. As soon as you abandon the sport, the lipase starts stuffing them with fat again.
Why is there so much fat?The body reserves not only fats, but also carbohydrates. Let's say you ate 100 calories of carbs. So, the body must burn approximately 23 calories to save the remaining 77 calories. But to save 100 extra "fat" calories, you need only 3 calories. The remaining 97 calories are all yours! So it turns out that fat reserves are always the largest.
Factors contributing to the deposition of fat in the body:
- Age (the older you are, the more “willingly” fat is deposited)
- Gender (Women accumulate fat faster)
- Overeating (you eat too much)
- Sedentary lifestyle (you don't need fat energy)
- Excess lipase (heredity factor)
- Nervous stress (contrary to popular belief, they get fat from stress)
- The habit of eating fat (we are talking about the features of national cuisine)
- Genetic factors (completeness is inherited).
How does exercise help to get rid of extra pounds? That's how. First, the body reacts to physical exercise with the consumption of glycogen - a pre-reserve sugar. And only then, when he spends "sugar" reserves, fat deposits come into play. This happens about half an hour after the start of aerobic training, i.e. just when many people usually turn it off.
Changing the figure
So much talk about genetics! Like, if your mom was full, then you will not escape the same fate. In fact, everything is not so scary. Genes determine your body composition by 25%. Only a quarter! This applies to the number of fat cells and where they cluster (in the waist or on the hips and buttocks). So, if you really look like mommy, it’s more likely because you share the same eating habits with her: you overeat just like her. If you start exercising and go on a diet, you will look completely different. By the way, strength exercises do not have to shy away. Muscles are a state within a state. Just like the brain, they are awake even when you are sleeping and expend energy. The more muscle you have, the higher your daily calorie expenditure. Are you afraid to turn into a masculine bodybuilder? A visually noticeable increase in muscles of 12-25 kg. However, bodybuilders have been going to this for decades. God forbid you add at least 5-8 kg!
It is easier for women - "apples" to drive off excess fat than "pears". Fat in the waist area is 5 times more pliable than on the hips and buttocks. But for women with a "pear" figure, there are methods. First, you need to understand that "burning" fat is part of your overall metabolism. It does not happen that the exchange is sluggish, and the fat "burns" quickly. So here's your first trick. Eat often - after 2-2.5 hours, but in small portions. This technique really "unwinds" the metabolic rate, and hence the "fat burning". Second. More aerobics! All these aerobic exercises for 40-45 minutes are not about you. Do aerobics for one and a half to two hours at least 4-5 days a week! And further. Fat "burns" oxygen. You need outdoor aerobics. Outdoors only! Third. Do not try to go on "hard" diets less than 1200 calories! It has been proven that such diets, on the contrary, slow down the metabolic rate, which automatically reduces the rate of "fat burning"!
Where does the body get energy from?The energy you need to lift a barbell or run a cross country can come from two sources. These are glycogen (carbohydrates) and fat. So how do you make yourself lose more fat? Here are the reasons that influence the "choice" of the organism:
- The food you ate before training (if you eat something high in carbohydrates, like a vegetable salad, cereal, fruit or chocolate, then the body will choose not fat as the main source of energy, but pre-stored sugar - glycogen.)
- Duration of training (the longer you exercise, the more fat will be consumed)
- Intensity of training (the higher the load, the more glycogen is consumed)
- Type of exercise (aerobics burns more fat, and exercise equipment burns more glycogen)
- Fitness level (the more "sporting experience" you have, the more fat you burn)
- Carbohydratestaken during training (if you decide to drink or eat something sweet, spend more glycogen).
 02.02.2020 21:05:00 |
Place 1-2 drops of vegetable oil (or other fat) in five test tubes. Pour 1 ml of ethyl alcohol into the first test tube, ethyl ether into the second, gasoline into the third, benzene into the fourth, and water into the fifth. Shake the contents of the tubes and let stand.
Does fat dissolve in all substances? Which substances are good fat dissolvers and which are bad? What conclusion can be drawn about the solubility of fats based on experience.
Output example.
1. Sunflower oil + water = the formation of an unstable emulsion, followed by a rapid separation of the mixture into two layers.
2. sunflower oil + ethyl alcohol = formation of a cloudy solution as a result of insufficient dissolution of the oil.
3. sunflower oil + benzene = the solution is almost transparent.
4. sunflower oil + gasoline = transparent solution. oil is completely soluble in gasoline
Completely soluble in ethyl ether
Vegetable oil, being non-polar, dissolves in non-polar solvents, i.e., in gasoline, ethyl ether
Water and alcohol are polar solvents; fat is poorly or practically insoluble in them.
Experience No. 2. Emulsification of fats. (Form the answer yourself if you have a hint)
Pour 3-4 drops of vegetable oil into five test tubes. Add 5 ml of water to the first test tube, 5% NaOH solution to the second, soda solution to the third, soap solution to the fourth, protein solution to the fifth. Shake the contents of each tube vigorously and observe the formation of an emulsion. Place the test tubes with the resulting emulsions in a rack for a few minutes.
In which test tube did separation occur? What substances give stable emulsions?
emulsion called a dispersion system consisting of two or more liquid phases, one of which (called the dispersion medium) is continuous.
If you take approximately the same amount of oil and water and mechanically, for example, with stirring, prepare an emulsion, then after that a rapid separation will occur.
The formation of stable emulsions occurs with the addition of surfactants.
Experience No. 3. Saponification of fats in a water-alcohol solution of alkali. (Video demonstration) Brief description of the experience.
Place 2 g of fat in a test tube and add 6 ml of a 15% alkali alcohol solution. Stir the mixture with a glass rod, fix the test tube in a rack and stopper under reflux. Place the test tube with the mixture in a water bath and heat for 12-15 minutes until boiling. Saponification is carried out until the liquid becomes homogeneous. To determine the end of saponification, pour a few drops of the resulting mixture into a test tube, add 6 ml of water and heat the solution. If the taken mixture dissolves in water without droplets of fat, then saponification can be considered complete. If there are drops of fat in the solution, then continue heating the mixture in a water bath for a few more minutes.
Add a saturated solution of NaOH to the resulting thick liquid. The liquid becomes cloudy and a layer of soap is released that floats to the surface. Let the mixture stand and cool the test tube with cold water, remove the resulting soap and leave for the next experiments.
Questions for self-examination: (answers in a notebook for highlighted questions)
1. What substances are fats?
2. What is the role of fats in the body?
3. What process is called rancidity?
4. Compare vegetable oils and animal fats in composition, properties and
application.
5. Describe methods for obtaining animal fats and vegetable oils.
6. What is a surfactant?
What types of surfactants are divided into by the nature of hydrophilic and hydrophobic groups?
What type of surfactant is ordinary soap?
9. What is liquid soap (detergents), solid soap? (Cosmetic and laundry soaps)
10. Write the reaction equations for the synthesis of fats from: a) palmitic acid and
glycerin; b) linoleic acid and glycerin. Name the resulting fats.
11. Make the equations for the reactions of obtaining: a) oleolinoleopalmitin; b) butyric acid triglyceride; c) diolostearin.
12. Describe all the changes that occur with fats during the technological processing of food.
"Hydrolysis of carbohydrates, denaturation of proteins".
A) Carbohydrates (Text to read and repeat)
Carbohydrates (sugars) are common in nature and play an important role in human life. They make up to 80% of the mass of dry matter of plants and about 2% of the dry matter of animal organisms.
The name carbohydrates arose due to the fact that at first substances were known whose composition could be expressed by the formula Cn (H 2 O) m.
Monosaccharides are polyhydric aldehyde or keto alcohols.
Polysaccharides are divided into sugar-like (oligosaccharides) and non-sugar-like. Low molecular weight (sugar-like) polysaccharides contain a small number (2-10) of monosyl residues in the molecule. They dissolve well in water, have a sweet taste and a pronounced crystalline structure. Some of them (maltose, lactose) reduce copper (P) ions (Fehling's liquid), they are called reducing, others (sucrose, trehalose) do not reduce, and therefore they are classified as non-reducing oligosaccharides.
High-molecular (non-sugar-like) polysaccharides contain from tens to several tens of thousands of monosaccharide residues; they are insoluble in water, tasteless and do not have a pronounced crystalline structure.
Of the monosaccharides, glucose and fructose are the most important.
Glucose (C 6 H 12 O 6) is a colorless crystalline substance that is soluble in water.
The study of the structure and properties showed that glucose can exist in various forms: aldehyde and two cyclic forms.
Glucose is found in many fruits and berries (grapes) and is formed in the body during the breakdown of disaccharides and starch in food. It is quickly and easily absorbed from the intestines into the blood and is used by the body as an energy source for the formation of glycogen in the liver, to nourish the tissues of the brain, muscles and maintain the required level of sugar in the blood.
Under the action of enzymes, glucose is fermented.