Lesson Objectives: repetition, generalization and systematization of knowledge on the topic "Fundamentals of Cytology"; development of skills to analyze, highlight the main thing; fostering a sense of collectivism, improving group work skills.
Equipment: materials for competitions, equipment and reagents for experiments, sheets with crossword grids.
1. The students of the class are divided into two teams, they choose captains. Each student has a badge that matches the number on the student record screen.
2. Each team makes a crossword puzzle for the opponents.
3. To evaluate the work of students, a jury is formed, which includes representatives of the administration and students of grade 11 (5 people in total).
The jury registers both team and individual results. The team that gets largest number points. Students receive grades depending on the number of points scored during competitions.
DURING THE CLASSES
1. Warm up
(Maximum score 15 points)
Team 1
1. Virus of bacteria - ... ( bacteriophage).
2. Colorless plastids - ... ( leucoplasts).
3. The process of absorption by a cell of large molecules of organic substances and even whole cells - ... ( phagocytosis).
4. An organoid containing centrioles in its composition, - ... ( cell center).
5. The most common cell substance is ... ( water).
6. Cell organoid, representing a system of tubules, performing the function of a "warehouse for finished products", - ( golgi complex).
7. An organelle in which energy is formed and accumulated - ... ( mitochondrion).
8. Catabolism (name synonyms) is ... ( dissimilation, energy metabolism).
9. An enzyme (explain the term) is ... ( biological catalyst).
10. Protein monomers are ... ( amino acids).
11. The chemical bond connecting the residues of phosphoric acid in the ATP molecule has the property ... ( macroergy).
12. Internal viscous semi-liquid contents of the cell - ... ( cytoplasm).
13. Multicellular organisms-phototrophs - ... ( plants).
14. Protein synthesis on ribosomes is ... ( broadcast).
15. Robert Hooke discovered cellular structure plant tissue in ... ( 1665
) year.
Team 2
1. Unicellular organisms without cell nucleus – ... (prokaryotes).
2. Plastids are green - ... ( chloroplasts).
3. The process of capture and absorption by the cell of liquid with substances dissolved in it - ... ( pinocytosis).
4. An organelle that serves as a site for protein assembly - ... ( ribosome).
5. Organic matter, the main substance of the cell - ... ( protein).
6. Organoid of a plant cell, which is a vial filled with juice, - ... ( vacuole).
7. An organoid involved in the intracellular digestion of food particles - ... ( lysosome).
8. Anabolism (name synonyms) is ... ( assimilation, plastic exchange).
9. Gene (explain the term) is ... ( segment of a DNA molecule).
10. The monomer of starch is ... ( glucose.).
11. Chemical bond connecting the monomers of the protein chain - ... ( peptide).
12. Component kernels (may be one or more) - ... ( nucleolus).
13. Heterotrophic organisms - ( animals, fungi, bacteria).
14. Several ribosomes united by mRNA are ... ( polysome).
15. D.I. Ivanovsky opened ... ( viruses), in... ( 1892
) year.
2. Pilot stage
Students (2 people from each team) receive instructional cards and perform the following laboratory work.
1. Plasmolysis and deplasmolysis in onion skin cells.
2. Catalytic activity of enzymes in living tissues.
3. Solving crossword puzzles
Teams solve crossword puzzles for 5 minutes and submit their work to the jury. The jury members sum up this stage.
Crossword 1
1. The most energy-intensive organic matter. 2. One of the ways in which substances enter the cell. 3. Vital essential substance not produced by the body. 4. Structure adjacent to the plasma membrane animal cell outside. 5. The composition of RNA includes nitrogenous bases: adenine, guanine, cytosine, and .... 6. The scientist who discovered single-celled organisms. 7. A compound formed by the polycondensation of amino acids. 8. Cell organelle, site of protein synthesis. 9. Folds formed by the inner membrane of the mitochondria. 10. The property of living things to respond to external influences.
Answers
1. Lipid. 2. Diffusion. 3. Vitamin. 4. Glycocalyx. 5. Uracil. 6. Levenguk. 7. Polypeptide. 8. Ribosome. 9. Christa. 10. Irritability.
Crossword 2
1. The capture of solid particles by the plasma membrane and their transport into the cell. 2. The system of protein filaments in the cytoplasm. 3. A compound consisting of a large number of amino acid residues. 4. Living beings unable to synthesize organic substances from inorganic. 5. Cellular organelles containing red and yellow pigments. 6. A substance whose molecules are formed by the combination of a large number of molecules with a low molecular weight. 7. Organisms that have nuclei in their cells. 8. The process of oxidizing glucose with its splitting to lactic acid. 9. smallest cell organelles composed of rRNA and protein. 10. Membrane structures connected to each other and to the inner membrane of the chloroplast.
Answers
1. Phagocytosis. 2. Cytoskeleton. 3. Polypeptide. 4. Heterotrophs. 5. Chromoplasts. 6. Polymer. 7. Eukaryotes. 8. Glycolysis. 9. Ribosomes. 10. Grans.
4. The third one is superfluous
(Maximum score 6 points)
Teams are offered compounds, phenomena, concepts, etc. Two of them are combined on a certain basis, and the third is superfluous. Find the odd word and justify the answer.
Team 1
1. Amino acid, glucose, table salt. ( Salt- inorganic matter.)
2. DNA, RNA, ATP. ( ATP is an energy storage.)
3. Transcription, translation, glycolysis. ( Glycolysis is the process of oxidizing glucose.)
Team 2
1. Starch, cellulose, catalase. ( Catalase is a protein, an enzyme.)
2. Adenine, thymine, chlorophyll. ( Chlorophyll is a green pigment.)
3. Reduplication, photolysis, photosynthesis. ( Reduplication - duplication of a DNA molecule.)
5. Filling in the tables
(Maximum score 5 points)
Each team selects one person; they are given sheets with tables 1 and 2, which must be filled out within 5 minutes.
Table 1. Stages of energy metabolism
Table 2. Characteristics of the photosynthesis process
Phases of photosynthesis |
starting materials |
Energy source |
end products |
biological meaning |
|
Luminous |
light, chlorophyll, heat |
H 2 O, enzymes, ADP, phosphoric acid |
light energy |
ATP, O 2, |
oxygen formation |
Dark |
ATP energy, minerals |
CO 2, ATP, H |
chemical energy (ATP) |
formation of organic matter |
6. Match numbers and letters
(Maximum score 7 points)
Team 1
1. Regulates water balance – ...
2. Directly involved in protein synthesis - ...
3. Is respiratory center cells...
4. Give an insect-attractive look to flower petals...
5. Consists of two perpendicular cylinders...
6. Act as reservoirs in plant cells...
7. They have constrictions and shoulders ...
8. Forms spindle fibers...
BUT- cell center.
B- chromosome.
AT- vacuoles.
G- cell membrane.
D- ribosome.
E- mitochondrion.
AND- chromoplasts.
(1 - G; 2 - D; 3 - E; 4 - F; 5 - A; 6 - B; 7 - B; 8 - A.)
Team 2
1. An organoid on the membranes of which protein synthesis occurs ...
2. Has grana and thylakoids...
3. Contains karyoplasm inside...
4. Consists of DNA and protein...
5. Has the ability to separate small bubbles...
6. Carries out self-digestion of the cell in conditions of lack of nutrients...
7. The component of the cell in which the organelles are located ...
8. Only found in eukaryotes...
BUT- lysosome.
B- chloroplast.
AT- nucleus.
G- cytoplasm.
D- Golgi complex.
E- endoplasmic reticulum.
AND- chromosome.
(1 - E; 2 - B; 3 - B; 4 - F; 5 - D; 6 - A; 7 - G; 8 - V.)
7. Select organisms - prokaryotes
(Maximum score 3 points)
Team 1
1. tetanus bacillus.
2. Penicillium.
3. Polypore.
4. Spirogyra.
5. Vibrio cholerae.
6. Yagel.
7. Streptococcus.
8. Hepatitis virus.
9. Diatoms.
10. Amoeba.
Team 2
1. Yeast.
2. Rabies virus.
3. Oncovirus.
4. Chlorella.
5. lactic acid bacteria.
6. iron bacteria.
7. Bacillus.
8. Infusoria shoe.
9. Laminaria.
10. Lichen.
8. Solve the problem
(Maximum score 5 points)
Team 1
Determine the mRNA and the primary structure of the protein encoded in the DNA region: G–T–T–C–T–A–A–A–A–G–G–C–C–A–T, if the 5th nucleotide is deleted, and between the 8th and 9th nucleotide there will be a thymidyl nucleotide.
(mRNA: C-A-A-G-U-U-U-U-A-T-C-C-G-U-A; glutamine – valine - leucine - proline - valine.)
Team 2
A section of the DNA chain is given: T–A–G–T–G–A–T–T–T–A–A–C–T–A–G
What will be the primary structure of the protein if, under the influence of chemical mutagens, the 6th and 8th nucleotides are replaced by cytidyl ones?
(mRNA: A-U-C-A-C-G-A-G-A-U-U-G-A-U-C; protein: isoleucine - threonine - arginine - leucine - isoleucine.)
9. Captains competition
(Maximum score 10 points)
Captains receive pencils and blank sheets of paper.
Task: draw the largest number of cell organelles and label them.
10. Your opinion
(Maximum score 5 points)
Team 1
Many life processes in the cell are accompanied by the expenditure of energy. Why are ATP molecules considered a universal energy substance - the only source of energy in a cell?
Team 2
The cell is constantly changing in the process of life. How does it keep its shape and chemical composition?
11. Summing up
The activities of students and teams are evaluated. The winning team is awarded.
Human food contains the main nutrients: proteins, fats, carbohydrates; vitamins, microelements, macronutrients. Since our whole life is a metabolism in nature, for a normal existence, an adult must eat three times a day, replenishing his "reserve" of nutrients.
In the body of a living person, the processes of oxidation (combination with oxygen) of various nutrients are continuously going on. Oxidation reactions are accompanied by the formation and release of heat necessary to maintain life processes organism. Thermal energy ensures the activity of the muscular system. Therefore, the harder the physical labor, the more food the body requires.
The energy value of food is usually expressed in calories. A calorie is the amount of heat required to heat 1 liter of water at 15°C by one degree. The calorie content of food is the amount of energy that is formed in the body as a result of the assimilation of food.
1 gram of protein, when oxidized in the body, releases an amount of heat equal to 4 kcal; 1 gram of carbohydrates = 4 kcal; 1 gram of fat = 9 kcal.
Squirrels
Proteins support the basic manifestations of life: metabolism, muscle contraction, nerve irritability, the ability to grow, expand, and think. Proteins are found in all tissues and body fluids, being their main part. Proteins are made up of a variety of amino acids that biological significance one protein or another.
Non-essential amino acids are formed in the human body. Essential amino acids enter the human body only with food. Therefore, for the physiologically complete life of the body, the presence in the food of all essential amino acids. A dietary deficiency of even one essential amino acid leads to a decrease in the biological value of proteins and can cause protein deficiency, despite a sufficient amount of protein in the diet. The main supplier of essential amino acids: meat, milk, fish, eggs, cottage cheese.
The human body also needs proteins. plant origin, which are found in bread, cereals, vegetables - they include non-essential amino acids. Products containing animal and vegetable proteins provide the body with substances that are necessary for its development and life.
The body of an adult should receive approximately 1 gram of protein per 1 kg of total weight. It follows that the "average" adult weighing 70 kg should receive at least 70 g of protein per day (55% of the protein should be of animal origin). With heavy physical exertion, the body's need for protein increases.
Proteins in the diet cannot be replaced by any other substances.
Fats
Fats surpass the energy of all other substances, are involved in recovery processes, being a structural part of cells and their membrane systems, serve as solvents for vitamins A, E, D, and contribute to their absorption. Also, fats contribute to the development of immunity and help the body to keep warm.
Lack of fat leads to disruption of the activity of the central nervous system, changes in the skin, kidneys, organs of vision.
The composition of fats contains polyunsaturated fatty acids, lecithin, vitamins A, E. The average need for an adult in fat is 80-100 g per day, including vegetable fat - 25..30 g.
Due to fat in food, a third of the daily energy value of the diet is provided; There are 37 g of fat per 1000 kcal.
Fats are found in sufficient quantities in the brain, heart, eggs, liver, butter, cheese, meat, lard, poultry, fish, milk. Especially valuable vegetable fats containing no cholesterol.
Carbohydrates
Carbohydrates are the main source of energy. Carbohydrates account for 50-70% of the daily caloric intake. The need for carbohydrates depends on the energy consumption of the body.
The daily requirement for carbohydrates for an adult engaged in mental or light physical labor is 300-500 g / day. In people engaged in heavy physical labor, the need for carbohydrates is much higher. In obese people, the energy content of the diet can be reduced by the amount of carbohydrates without compromising health.
Bread, cereals, pasta, potatoes, sugar (net carbohydrate) are rich in carbohydrates. An excess of carbohydrates in the body correct ratio the main parts of food, thereby disrupting the metabolism.
vitamins
Vitamins are not energy providers. However, they are needed in small amounts to maintain normal life body, regulating, directing and accelerating metabolic processes. The vast majority of vitamins are not produced in the body, but come from outside with food.
With a lack of vitamins in food, hypoavitaminosis develops (more often in winter and spring) - fatigue increases, weakness, apathy are observed, efficiency decreases, body resistance decreases.
The actions of vitamins in the body are interconnected - the lack of one of the vitamins entails a metabolic disorder of other substances.
All vitamins are divided into two groups: water soluble vitamins and fat soluble vitamins.
Fat soluble vitamins- vitamins A, D, E, K.
Vitamin A- affects the growth of the body, its resistance to infections, it is necessary to maintain normal vision, the condition of the skin and mucous membranes. Vitamin A is rich in fish oil, cream, butter, egg yolk, liver, carrots, lettuce, spinach, tomatoes, green pea, apricots, oranges.
Vitamin D- promotes education bone tissue stimulates the growth of the organism. A lack of vitamin D in the body leads to disruption of the normal absorption of calcium and phosphorus, causing rickets. Vitamin D is rich in fish oil, egg yolk, liver, fish roe. There is little vitamin D in milk and butter.
Vitamin K- participates in tissue respiration, blood clotting. Vitamin K is synthesized in the body by intestinal bacteria. The cause of vitamin K deficiency is diseases of the digestive system or intake antibacterial drugs. Vitamin K is rich in tomatoes, green parts of plants, spinach, cabbage, nettles.
Vitamin E(tocopherol) affects activity endocrine glands, on the exchange of proteins, carbohydrates, provides intracellular metabolism. Vitamin E favorably affects the course of pregnancy and fetal development. Vitamin E is rich in corn, carrots, cabbage, green peas, eggs, meat, fish, olive oil.
Water Soluble Vitamins- vitamin C, B vitamins.
Vitamin C (vitamin C) - actively participates in redox processes, affects carbohydrate and protein metabolism increases the body's resistance to infections. Rich in vitamin C, rose hips, black currants, chokeberry, sea buckthorn, gooseberry, citrus fruits, cabbage, potatoes, leafy vegetables.
To the group vitamins B includes 15 independent vitamins, soluble in water, which take part in the metabolic processes in the body, the process of hematopoiesis, play an important role in carbohydrate, fat, water metabolism. B vitamins are growth promoters. Rich in B vitamins, brewer's yeast, buckwheat, oat groats, rye bread, milk, meat, liver, egg yolk, green plant parts.
Microelements and macroelements
Minerals are part of the cells and tissues of the body, are involved in a variety of metabolic processes. Macronutrients are needed by the body in relatively large quantities: calcium, potassium, magnesium, phosphorus, chlorine, sodium salts. Trace elements are needed in very small quantities: iron, zinc, manganese, chromium, iodine, fluorine.
Iodine is found in seafood, cereals, yeast, legumes, and liver are rich in zinc; copper and cobalt are found in beef liver, kidneys, yolk chicken egg, honey. Berries and fruits contain a lot of potassium, iron, copper, phosphorus.
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At the end of the 19th century, a branch of biology called biochemistry was formed. It studies the chemical composition of a living cell. The main task of science is the knowledge of the characteristics of metabolism and energy that regulate the vital activity of plant and animal cells.
The concept of the chemical composition of the cell
As a result of careful research, scientists studied the chemical organization of cells and found that living beings contain more than 85 chemical elements. Moreover, some of them are obligatory for almost all organisms, while others are specific and are found in specific biological species. And the third group of chemical elements is present in the cells of microorganisms, plants and animals in fairly small quantities. Chemical elements cells are most often in the form of cations and anions, from which mineral salts and water, as well as the synthesis of carbonaceous organic compounds: carbohydrates, proteins, lipids.
Organogenic elements
In biochemistry, these include carbon, hydrogen, oxygen, and nitrogen. Their totality in the cell is from 88 to 97% of the other chemical elements in it. Carbon is especially important. All organic matter Cells are made up of molecules containing carbon atoms. They are able to connect with each other, forming chains (branched and unbranched), as well as cycles. This ability of carbon atoms underlies the amazing variety of organic substances that make up the cytoplasm and cellular organelles.
For example, the internal content of the cell consists of soluble oligosaccharides, hydrophilic proteins, lipids, various types of ribonucleic acid: transfer RNA, ribosomal RNA and messenger RNA, as well as free monomers - nucleotides. It also has a similar chemical composition and contains deoxyribonucleic acid molecules that are part of the chromosomes. All of the above compounds contain atoms of nitrogen, carbon, oxygen, hydrogen. This is proof of their particularly important significance, since the chemical organization of cells depends on the content of organogenic elements that make up cellular structures: hyaloplasm and organelles.
Macronutrients and their meanings
Chemical elements, which are also very common in the cells of various types of organisms, are called macronutrients in biochemistry. Their content in the cell is 1.2% - 1.9%. The macroelements of the cell include: phosphorus, potassium, chlorine, sulfur, magnesium, calcium, iron and sodium. All of them perform important functions and are part of various cell organelles. So, the ferrous ion is present in the blood protein - hemoglobin, which transports oxygen (in this case it is called oxyhemoglobin), carbon dioxide(carbohemoglobin) or carbon monoxide(carboxyhemoglobin).
Sodium ions provide the most important species intercellular transport: the so-called sodium-potassium pump. They are also part of the interstitial fluid and blood plasma. Magnesium ions are present in chlorophyll molecules (photopigment of higher plants) and participate in the process of photosynthesis, as they form reaction centers that capture photons of light energy.
Calcium ions provide the conduction of nerve impulses along the fibers, and are also the main component of osteocytes - bone cells. Calcium compounds are widely distributed in the world of invertebrates, whose shells are composed of calcium carbonate.
Chlorine ions take part in the recharging of cell membranes and provide the appearance electrical impulses underlying nervous excitation.
Sulfur atoms are part of native proteins and determine their tertiary structure by "crosslinking" the polypeptide chain, resulting in the formation of a globular protein molecule.
Potassium ions are involved in the transport of substances across cell membranes. Phosphorus atoms are part of such an important energy-intensive substance as adenosine triphosphoric acid, and are also important component molecules of deoxyribonucleic and ribonucleic acids, which are the main substances of cellular heredity.
Functions of trace elements in cellular metabolism
About 50 chemical elements that make up less than 0.1% in cells are called trace elements. These include zinc, molybdenum, iodine, copper, cobalt, fluorine. With a small content, they perform very important functions, as they are part of many biologically active substances.
For example, zinc atoms are found in the molecules of insulin (a pancreatic hormone that regulates blood glucose levels), iodine is integral part hormones thyroid gland- thyroxine and triiodothyronine, which control the level of metabolism in the body. Copper, along with iron ions, is involved in hematopoiesis (the formation of red blood cells, platelets and white blood cells in red bone marrow vertebrates). Copper ions are part of the hemocyanin pigment present in the blood of invertebrates, such as molluscs. Therefore, the color of their hemolymph is blue.
Even less content in the cell of such chemical elements as lead, gold, bromine, silver. They are called ultramicroelements and are part of plant and animal cells. For example, in corn kernels chemical analysis gold ions were detected. Bromine atoms in in large numbers are part of the cells of the thallus of brown and red algae, such as sargassum, kelp, fucus.
All the previously given examples and facts explain how the chemical composition, functions and structure of the cell are interconnected. The table below shows the content of various chemical elements in the cells of living organisms.
General characteristics of organic substances
Chemical properties of cells various groups organisms in a certain way depend on carbon atoms, the proportion of which is more than 50% of the cell mass. Almost all dry matter of the cell is represented by carbohydrates, proteins, nucleic acids and lipids, which have complex structure and big molecular weight. Such molecules are called macromolecules (polymers) and consist of simpler elements - monomers. Protein substances play an extremely important role and perform many functions, which will be discussed below.
The role of proteins in the cell
compounds included in living cell, confirms high content it contains organic substances such as proteins. There is a logical explanation for this fact: proteins perform various functions and participate in all manifestations of cellular life.
For example, it consists in the formation of antibodies - immunoglobulins produced by lymphocytes. Protective proteins such as thrombin, fibrin and thromboblastin provide blood clotting and prevent its loss during injuries and wounds. The composition of the cell includes complex proteins of cell membranes that have the ability to recognize foreign compounds - antigens. They change their configuration and inform the cell about potential danger (signaling function).
Some proteins perform a regulatory function and are hormones, for example, oxytocin, produced by the hypothalamus, is reserved by the pituitary gland. Coming from it into the blood, oxytocin acts on the muscular walls of the uterus, causing it to contract. The protein vasopressin also has a regulatory function, controlling blood pressure.
AT muscle cells there are actin and myosin that can contract, which causes motor function muscle tissue. For proteins, it is characteristic and, for example, albumin is used by the embryo as a nutrient for its development. Blood proteins of various organisms, such as hemoglobin and hemocyanin, carry oxygen molecules - they perform a transport function. If more energy-intensive substances such as carbohydrates and lipids are fully utilized, the cell proceeds to break down proteins. One gram of this substance gives 17.2 kJ of energy. One of essential functions proteins is catalytic (enzyme proteins accelerate chemical reactions occurring in compartments of the cytoplasm). Based on the foregoing, we were convinced that proteins perform many very important functions and are necessarily part of the animal cell.
Protein biosynthesis
Consider the process of protein synthesis in a cell, which occurs in the cytoplasm with the help of organelles such as ribosomes. Thanks to the activity of special enzymes, with the participation of calcium ions, ribosomes are combined into polysomes. The main functions of ribosomes in a cell are the synthesis of protein molecules, which begins with the process of transcription. As a result, mRNA molecules are synthesized, to which polysomes are attached. Then the second process begins - translation. Transfer RNAs are linked to twenty various types amino acids and bring them to polysomes, and since the functions of ribosomes in a cell are the synthesis of polypeptides, these organelles form complexes with tRNA, and amino acid molecules are linked by peptide bonds, forming a protein macromolecule.
The role of water in metabolic processes
Cytological studies have confirmed the fact that the cell, the structure and composition of which we are studying, on average, consists of 70% water, and in many animals leading an aquatic way of life (for example, coelenterates), its content reaches 97-98%. With this in mind, the chemical organization of cells includes hydrophilic (capable of dissolving) and Being a universal polar solvent, water plays an exceptional role and directly affects not only the functions, but also the very structure of the cell. The table below shows the water content of the cells. various types living organisms.
The function of carbohydrates in the cell
As we found out earlier, carbohydrates also belong to important organic substances - polymers. These include polysaccharides, oligosaccharides and monosaccharides. Carbohydrates are part of more complex complexes - glycolipids and glycoproteins, from which cell membranes and supra-membrane structures, such as glycocalyx, are built.
In addition to carbon, carbohydrates include oxygen and hydrogen atoms, and some polysaccharides also contain nitrogen, sulfur and phosphorus. There are many carbohydrates in plant cells: potato tubers contain up to 90% starch, seeds and fruits contain up to 70% carbohydrates, and in animal cells they are found in the form of compounds such as glycogen, chitin and trehalose.
Simple sugars (monosaccharides) have general formula CnH2nOn and are divided into tetroses, trioses, pentoses and hexoses. The last two are the most common in the cells of living organisms, for example, ribose and deoxyribose are part of nucleic acids, and glucose and fructose take part in assimilation and dissimilation reactions. Oligosaccharides are often found in plant cells: sucrose is stored in the cells of sugar beet and sugar cane, maltose is found in germinated grains of rye and barley.
Disaccharides have a sweetish taste and dissolve well in water. Polysaccharides, being biopolymers, are mainly represented by starch, cellulose, glycogen and laminarin. Chitin belongs to the structural forms of polysaccharides. The main function of carbohydrates in the cell is energy. As a result of hydrolysis and energy metabolism reactions, polysaccharides are broken down to glucose, and it is then oxidized to carbon dioxide and water. As a result, one gram of glucose releases 17.6 kJ of energy, and the reserves of starch and glycogen, in fact, are a reservoir of cellular energy.
Glycogen is deposited mainly in muscle tissue and liver cells, vegetable starch - in tubers, bulbs, roots, seeds, and in arthropods, such as spiders, insects and crustaceans, leading role trehalose oligosaccharide plays an important role in energy supply.
There is another function of carbohydrates in the cell - building (structural). It lies in the fact that these substances are the supporting structures of cells. For example, cellulose is part of the cell walls of plants, chitin forms the outer skeleton of many invertebrates and is found in fungal cells, olisaccharides, together with lipid and protein molecules, form a glycocalyx - an epimembrane complex. It provides adhesion - adhesion of animal cells to each other, leading to the formation of tissues.
Lipids: structure and functions
These organic substances, which are hydrophobic (insoluble in water), can be recovered, that is, extracted from cells, using non-polar solvents such as acetone or chloroform. The functions of lipids in a cell depend on which of the three groups they belong to: fats, waxes, or steroids. Fats are most widely distributed in all cell types.
Animals accumulate them in the subcutaneous adipose tissue, the nervous tissue contains fat in the form of nerves. It also accumulates in the kidneys, liver, in insects - in fat body. Liquid fats - oils - are found in the seeds of many plants: cedar, peanut, sunflower, olive. The content of lipids in cells ranges from 5 to 90% (in adipose tissue).
Steroids and waxes differ from fats in that they do not contain residues in their molecules. fatty acids. So, steroids are hormones of the adrenal cortex that affect puberty body and are components of testosterone. They are also part of vitamins (for example, vitamin D).
The main functions of lipids in the cell are energy, building and protective. The first is due to the fact that 1 gram of fat during splitting gives 38.9 kJ of energy - much more than other organic substances - proteins and carbohydrates. In addition, during the oxidation of 1 g of fat, almost 1.1 g is released. water. That is why some animals, having a store of fat in their body, can for a long time be without water. For example, gophers can hibernate for more than two months without needing water, and a camel does not drink water when crossing the desert for 10-12 days.
The building function of lipids is that they are an integral part of cell membranes, and are also part of the nerves. Protective function lipid is that layer of fat under the skin around the kidneys and other internal organs protects them from mechanical injuries. The specific thermal insulation function is inherent in animals, long time in the water: whales, seals, fur seals. A thick subcutaneous fat layer, for example, in a blue whale is 0.5 m, it protects the animal from hypothermia.
Importance of oxygen in cellular metabolism
Aerobic organisms, which include the vast majority of animals, plants and humans, use atmospheric oxygen for energy metabolism reactions leading to the breakdown of organic substances and the release of a certain amount of energy accumulated in the form of adenosine triphosphoric acid molecules.
So, with the complete oxidation of one mole of glucose, which occurs on the cristae of mitochondria, 2800 kJ of energy is released, of which 1596 kJ (55%) is stored in the form of ATP molecules containing macroergic bonds. Thus, the main function of oxygen in the cell - the implementation of which is based on a group of enzymatic reactions of the so-called occurring in cell organelles - mitochondria. In prokaryotic organisms - phototrophic bacteria and cyanobacteria - the oxidation of nutrients occurs under the action of oxygen diffusing into cells on the internal outgrowths of plasma membranes.
We have studied the chemical organization of cells, as well as the processes of protein biosynthesis and the function of oxygen in cellular energy metabolism.
Nutrients - carbohydrates, proteins, vitamins, fats, trace elements, macronutrients- Found in food. All these nutrients are necessary for a person to be able to carry out all life processes. The nutrient content of the diet is the most important factor for compiling diet menus.
In the body of a living person, the processes of oxidation of all kinds never stop. nutrients. Oxidation reactions occur with the formation and release of heat, which a person needs to maintain life processes. Thermal energy allows you to work muscular system, which leads us to the conclusion that the harder the physical labor, the more food is required for the body.
The energy value of foods is determined by calories. The calorie content of foods determines the amount of energy received by the body in the process of assimilation of food.
1 gram of protein in the process of oxidation gives an amount of heat of 4 kcal; 1 gram of carbohydrates = 4 kcal; 1 gram of fat = 9 kcal.
Nutrients are proteins.
Protein as a nutrient necessary for the body to maintain metabolism, muscle contraction, nerve irritability, the ability to grow, reproduce, and think. Protein is found in all tissues and body fluids and is essential elements. A protein consists of amino acids that determine the biological significance of a protein.
Non-essential amino acids formed in the human body. Essential amino acids a person receives from the outside with food, which indicates the need to control the amount of amino acids in food. A dietary deficiency of even one essential amino acid leads to a decrease in the biological value of proteins and can cause protein deficiency, despite enough protein content in the diet. The main source of essential amino acids are fish, meat, milk, cottage cheese, eggs.
In addition, the body needs vegetable proteins contained in bread, cereals, vegetables - they provide essential amino acids.
Approximately 1 g of protein per 1 kilogram of body weight should enter the body of an adult every day. That is ordinary person, weighing 70 kg per day, you need a minimum of 70 g of protein, while 55% of all protein should be of animal origin. If you are doing exercise, then the amount of protein should be increased to 2 grams per kilogram per day.
Proteins in proper diet irreplaceable by any other elements.
Nutrients are fats.
Fats as nutrients are one of the main sources of energy for the body, participate in recovery processes, as they are a structural part of cells and their membrane systems, dissolve and help in the absorption of vitamins A, E, D. In addition, fats help in the formation of immunity and keep the body warm .
An insufficient amount of fat in the body causes disturbances in the activity of the central nervous system, changes in the skin, kidneys, and vision.
Fat consists of polyunsaturated fatty acids, lecithin, vitamins A, E. An ordinary person needs about 80-100 grams of fat per day, of which vegetable origin should be at least 25-30 grams.
Fat from food gives the body 1/3 of the daily energy value of the diet; There are 37 g of fat per 1000 kcal.
The required amount of fat in: heart, poultry, fish, eggs, liver, butter, cheese, meat, lard, brains, milk. Vegetable fats, which contain less cholesterol, are more important for the body.
Nutrients are carbohydrates.
Carbohydrates,nutrient, are the main source of energy, which brings 50-70% of calories from the entire diet. The required amount of carbohydrates for a person is determined based on his activity and energy consumption.
On the day of an ordinary person who is engaged in mental or light physical labor, about 300-500 grams of carbohydrates are needed. With the increase physical activity increases and daily rate carbohydrates and calories. For full people, the energy intensity of the daily menu can be reduced due to the amount of carbohydrates without compromising health.
A lot of carbohydrates are found in bread, cereals, pasta, potatoes, sugar (net carbohydrate). An excess of carbohydrates in the body disrupts the correct ratio of the main parts of food, thereby disrupting metabolism.
Nutrients are vitamins.
vitamins,as nutrients, do not provide energy to the body, but still are the most important nutrients necessary for the body. Vitamins are needed to maintain the vital activity of the body, regulating, directing and accelerating metabolic processes. Almost all vitamins the body receives from food and only a few can be produced by the body itself.
In winter and spring, hypoavitaminosis may occur in the body due to a lack of vitamins in food - fatigue, weakness, apathy increase, efficiency and body resistance decrease.
All vitamins, according to their effect on the body, are interconnected - a lack of one of the vitamins leads to a metabolic disorder of other substances.
All vitamins are divided into 2 groups: water soluble vitamins and fat soluble vitamins.
Fat-soluble vitamins - vitamins A, D, E, K.
Vitamin A- necessary for the growth of the body, improving its resistance to infections, maintaining good vision, conditions of the skin and mucous membranes. Vitamin A comes from fish oil, cream, butter, egg yolk, liver, carrots, lettuce, spinach, tomatoes, green peas, apricots, oranges.
Vitamin D- is needed for the formation of bone tissue, growth of the body. A lack of vitamin D leads to a deterioration in the absorption of Ca and P, which leads to rickets. Vitamin D can be obtained from fish oil, egg yolk, liver, fish caviar. Vitamin D is still found in milk and butter, but just a little bit.
Vitamin K- needed for tissue respiration, normal blood clotting. Vitamin K is synthesized in the body by intestinal bacteria. The lack of vitamin K appears due to diseases of the digestive system or the use of antibacterial drugs. Vitamin K can be obtained from tomatoes, green parts of plants, spinach, cabbage, nettles.
Vitamin E (tocopherol) is needed for the activity of the endocrine glands, the metabolism of proteins, carbohydrates, providing intracellular metabolism. Vitamin E favorably affects the course of pregnancy and fetal development. Vitamin E is obtained from corn, carrots, cabbage, green peas, eggs, meat, fish, olive oil.
Water-soluble vitamins - vitamin C, B vitamins.
Vitamin C (ascorbic acid) - is needed for the redox processes of the body, carbohydrate and protein metabolism, increasing the body's resistance to infections. Vitamin C is rich in rose hips, black currants, chokeberries, sea buckthorn, gooseberries, citrus fruits, cabbage, potatoes, leafy vegetables.
Vitamin B group includes 15 water-soluble vitamins that take part in metabolic processes in the body, the process of hematopoiesis, play an important role in carbohydrate, fat, water metabolism. B vitamins stimulate growth. You can get B vitamins from brewer's yeast, buckwheat, oatmeal, rye bread, milk, meat, liver, egg yolk, green parts of plants.
Nutrients are micronutrients and macronutrients.
Nutrient Minerals are part of the cells and tissues of the body, participate in various processes metabolism. Macroelements are necessary for a person in relatively large quantities: Ca, K, Mg, P, Cl, Na salts. Trace elements are needed in small quantities: Fe, Zn, manganese, Cr, I, F.
Iodine can be obtained from seafood; zinc from cereals, yeast, legumes, liver; copper and cobalt are obtained from beef liver, kidneys, egg yolk, honey. Berries and fruits contain a lot of potassium, iron, copper, phosphorus.
20. Chemical elements that make up carbons
21. Number of molecules in monosaccharides
22. Number of monomers in polysaccharides
23. Glucose, fructose, galactose, ribose and deoxyribose are classified as substances
24. Monomer of polysaccharides
25. Starch, chitin, cellulose, glycogen belongs to the group of substances
26. Reserve carbon in plants
27. Reserve carbon in animals
28. Structural carbon in plants
29. Structural carbon in animals
30. Molecules are made up of glycerol and fatty acids
31. Most Energy-Hungry Organic Nutrient
32. The amount of energy released during the breakdown of proteins
33. The amount of energy released during the breakdown of fats
34. The amount of energy released during the decay of carbons
35. Instead of one of the fatty acids, phosphoric acid is involved in the formation of the molecule
36. Phospholipids are part of
37. Protein monomers are
38. The number of types of amino acids in the composition of proteins exists
39. Proteins - catalysts
40. Diversity of protein molecules
41. In addition to enzymatic, one of the most important functions of proteins
42. There are most of these organic substances in the cell
43. According to the type of substances, enzymes are
44. Nucleic acid monomer
45. DNA nucleotides can differ from each other only
46. common substance DNA and RNA nucleotides
47. Carbohydrate in DNA Nucleotides
48. Carbohydrate in RNA Nucleotides
49. Only DNA is characterized by a nitrogenous base
50. Only RNA is characterized by a nitrogenous base
51. Double-stranded Nucleic acid
52. Single Stranded Nucleic Acid
56. Adenine is complementary
57. Guanine is complementary
58. Chromosomes consist of
59. Total types of RNA exist
60. RNA is in the cell
61. The role of the ATP molecule
62. Nitrogenous base in ATP molecule
63. Type of carbohydrate ATP
galactose, ribose and deoxyribose belong to the type of substances 24. Monomer polysaccharides 25. Starch, chitin, cellulose, glycogen belong to the group of substances 26. Reserve carbon in plants 27. Reserve carbon in animals 28. Structural carbon in plants 29. Structural carbon in animals 30. Molecules are made up of glycerol and fatty acids 31. The most energy-intensive organic nutrient 32. The amount of energy released from the breakdown of proteins 33. The amount of energy released from the breakdown of fats 34. The amount of energy released from the breakdown of carbons 35. Instead of one of the fatty acids phosphoric acid is involved in the formation of the molecule 36. Phospholipids are part of 37. The monomer of proteins is 38. The number of types of amino acids in the composition of proteins exists 39. Proteins are catalysts 40. A variety of protein molecules 41. In addition to enzymatic, one of the most important functions of proteins 42. These organic The most substances in the cell are 43. By the type of substances, enzymes are 44. Nucleic acid monomer 45. DNA nucleotides can differ from each other only 46. Common substance DNA and RNA nucleotides 47. Carbohydrate in DNA Nucleotides 48. Carbohydrate in RNA Nucleotides 49. Only DNA is characterized by a nitrogenous base 50. Only RNA is characterized by a nitrogenous base 51. Double-stranded Nucleic acid 52. Single-strand Nucleic acid 53. Types of chemical bond between nucleotides in one DNA strand 54. Types of chemical bond between DNA strands 55. Double hydrogen bond in DNA occurs between 56. Adenine is complementary 57. Guanine is complementary 58. Chromosomes consist of 59. Total there are 60 types of RNA. RNA is in the cell 61. The role of the ATP molecule 62. The nitrogenous base in the ATP molecule 63. The type of ATP carbohydrate
1) Nutrients are essential for building bodies:A) only animals
B) only plants
C) only mushrooms
D) all living organisms
2) Obtaining energy for the life of the body occurs as a result of:
A) breeding
B) breathing
C) selection
D) growth
3) For most plants, birds, animals, the habitat is:
A) ground-air
B) water
C) another organism
D) soil
4) Flowers, seeds and fruits are characteristic of:
A) coniferous plants
B) flowering plants
C) club mosses
D) ferns
5) Animals can breed:
A) disputes
B) vegetatively
C) sexually
D) cell division
6) In order not to get poisoned, you need to collect:
A) young edible mushrooms
B) mushrooms along highways
C) poisonous mushrooms
D) edible overgrown mushrooms
7) Stock minerals in soil and water is replenished due to vital activity:
A) manufacturers
B) destroyers
C) consumers
D) all answers are correct
8 - Pale Grebe:
A) creates organic matter in the light
B) digest nutrients into digestive system
C) absorb nutrients by hyphae
D) captures nutrients with pseudopods
9) Insert a link into the power circuit, choosing from the following:
Oats - mouse - kestrel - .......
A) hawk
B) meadow rank
C) earthworm
D) swallow
10) The ability of organisms to respond to changes environment called:
A) selection
B) irritability
C) development
D) metabolism
11) The habitat of living organisms is affected by factors:
A) inanimate nature
B) wildlife
C) human activity
D) all of the above factors
12) The absence of a root is typical for:
A) coniferous plants
B) flowering plants
C) mosses
D) ferns
13) The body of protists cannot:
A) be unicellular
B) be multicellular
C) have organs
D) there is no correct answer
14) As a result of photosynthesis, spirogyra chloroplasts form (are):
A) carbon dioxide
B) water
C) mineral salts
D) there is no correct answer
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