How does a cell use nutrients captured from the external environment?
There are only two fundamentally different options.
Nutrient molecules can be used to build other molecules that perform some more or less important functions in the life of the cell, for example, various molecules that make up the cell membrane. This way the cell uses nutrients is called assimilation.
Another option is to essentially burn them. If you set fire to, for example, a piece of sugar or wood, it will burn, releasing energy in the form of light and heat. A similar process occurs with individual food molecules during respiration. The energy that is released in this case is used by the cell, for example, for movement or for capturing new food particles. This type of use of substances is called dissimilation.
Phagocytosis("phagos" - "devourer", "cytos" - "cell") - feeding the cell with relatively large food parts cells (including other cells). The general picture of phagocytosis is shown in Fig. 12. A food particle floating past the cell touches the membrane and sticks to it (1,2). The membrane beneath it bends, enveloping the particle from all sides (3). As a result, a membrane bubble with a particle inside is formed - digestive vacuole(4). It breaks away from the membrane and floats deep into the cytoplasm.
The mechanism of formation of the digestive vacuole during phagocytosis. In most cells, two independent mechanisms operate.
The first of them is a simple consequence of the mechanism of adhesion of the food particle to the membrane. Due to the thermal movement of water molecules, both the food particle and the membrane receptors vibrate slightly all the time. Therefore, receptors and ligands that are closely located, but have not yet connected with each other, collide and stick together after a short time. It turns out that the membrane sticks more and more to the food particle from all sides.
The second mechanism is ensured by the work of special proteins, one end of which attaches to membrane receptors already adhered to ligands on the food particle, and the other to microtubules located under the membrane. These proteins are able to move along microtubules deep into the cytoplasm, “dragging behind them” receptors anchored in the membrane. As a result of the work of many of these proteins, the entire piece of membrane adhered to the food particle is immersed inside the cell, “on the fly” closing into a bubble.
So, the digestive vacuole ends up in the cytoplasm. There it merges with another bubble ( primary lysosome- from the words “lysis” - “dissolution, splitting” and “soma” - “body”), separated from the Golgi complex. The bubble - the result of this merger - is called secondary lysosome. After this, the food particle begins to dissolve. After 20 minutes, only a few small shapeless pieces are visible inside the secondary lysosome, which for some reason “did not want” to dissolve. Then the secondary lysosome swims up to the cell membrane and merges with it, throwing these “pieces” out of the cell. Another option, much more acceptable for multicellular animals, is that the secondary lysosome throws undigested residues into a special storage vacuole for “eternal storage.”
All these transformations occur due to the activity of special molecules. The following figure shows the molecules of a cell membrane (they are called receptors), ensuring the adhesion of the food particle to the membrane and the formation of a digestive vacuole. Receptors are molecules in the cell membrane that can recognize other molecules ( ligands), and stick to them firmly. A particle that touches the membrane sticks if on its surface there are ligands to some receptors present on the surface of the cell (there are usually about 100 different types of receptors on the membrane, and each of them “recognizes” a specific ligand).
Dissolution of food particles in the secondary lysosome(steps 5-7)
In this particular case, let the cell capture another cell, albeit a small one, using phagocytosis. The primary lysosome brought special molecules from the Golgi complex ( digestive enzymes), able to “cut” large molecules (for example, polymers) into pieces. Because of this, the organelles of the captured cell “fall apart” into individual small molecules.
The membrane of the secondary lysosome also contains carrier proteins, which are able to transfer these small molecules through the membrane into the cytoplasm of the cell.
In addition to lipids, the membrane contains a large number of molecules proteins. Some of them are immersed in the lipid bilayer, others are attached to the lipid heads and are entirely located either outside or inside the cell. The outer surface of the cell membrane differs from the inner one: here short chains of monosaccharide residues are attached to the lipid heads and proteins - oligosaccharides. Together they form a “sugar coat” on the surface of the cell - glycocalyx.
digestive vacuole
Membrane vesicles in the cytoplasm of the cell in which intracellular digestion occurs in protozoa and sponges. Formed by ingestion of solid formed particles or cells ( phagocytosis), as well as liquid droplets ( pinocytosis). Digestion of food particles by vacuoles is called cyclosis (lasts about 1 hour). During cyclosis, enzymes enter the digestive vacuole and digest the contents, the reaction of which changes from acidic to alkaline. Undigested residues are removed through powder.
.(Source: “Biology. Modern illustrated encyclopedia.” Chief editor A. P. Gorkin; M.: Rosman, 2006.)
- - a set of digestive organs in animals. Protozoa are characterized by intracellular digestion. In the most primitive multicellular organisms, food digestion is carried out separately. cells...
Biological encyclopedic dictionary
- - Cm....
Dictionary of microbiology
- - a single-membrane cell organelle filled with cell sap and separated from the hyaloplasm by the tonoplast. Contains water-soluble compounds - products of cell metabolism, reserve substances, pigments...
Anatomy and morphology of plants
- - a set of digestive organs in animals and humans. In vertebrates it is represented by the oral cavity, pharynx, esophagus, stomach, intestines, as well as the cri. digests. glands...
Natural science. encyclopedic Dictionary
- - a cavity in the protoplasm of a cell, filled with cell sap, in which salts, sugars and organic acids are dissolved, and also contains a number of pigments that color flower petals red, blue and purple...
The Beginnings of Modern Natural Science
- - ensures the body absorbs the nutrients it needs as a source of energy, as well as for cell renewal and growth...
Atlas of Human Anatomy
- - vacuole - A cavity in the cytoplasm of a cell, bounded by a membrane, filled with a liquid including enzymes...
Molecular biology and genetics. Dictionary
- - a set of organs that ensure the processing and assimilation of food necessary for the life of the body...
Medical encyclopedia
- - a cellular inclusion, which is a vesicle, usually with liquid contents...
Large medical dictionary
- - see Digestive tract...
Large medical dictionary
- - see Digestive apparatus...
Large medical dictionary
- - digestive apparatus, a set of digestive organs in animals and humans...
Great Soviet Encyclopedia
- - R., D., Ave. vacuo/li...
Spelling dictionary of the Russian language
- - vacuole cm....
Explanatory Dictionary by Efremova
- - VACUOL and VACUOL and, g. vacuole, lat. vacuola Small, usually spherical cavities in the cells of animals, plants and single-celled organisms. BAS-2. Vacuoles appeared in the protoplasm, colored by similar films...
Historical Dictionary of Gallicisms of the Russian Language
- - ...
Word forms
"digestive vacuole" in books
Digestive system
From the book Home Medical Encyclopedia. Symptoms and treatment of the most common diseases author Team of authorsDigestive system The digestive system is a group of organs of the human body in which processes of food processing, breakdown and absorption of nutrients necessary for the functioning of all cells of the body occur. Through it from the body
Digestive system
From the book Universal Encyclopedic Reference author Isaeva E. L.Digestive system Upper lipAscending colonPharynxDuodenumStomachGall bladderTeethSoft palateExternal anal sphincterLower lipDescending colonCommon bile ductParotid salivary
Digestive system
From the book Great Soviet Encyclopedia (PI) by the author TSB35. Digestive system
From the book Histology author Barsukov V Yu35. Digestive system The human digestive system is a digestive tube with glands located next to it (salivary glands, liver and pancreas), the secretion of which is involved in the digestion process. Digestion process
39. Digestive system
From the book Histology author Barsukov V Yu39. Digestive system StomachSecretary. The function is to produce gastric juice by the glands. The mechanical function of the stomach is to mix food with gastric juice and push processed food into the duodenum. Endocrine function
43. Digestive system
From the book Histology author Barsukov V Yu43. Digestive system Pancreas The pancreas is an organ of the digestive system, which contains exocrine and endocrine parts. The exocrine part is responsible for the production of pancreatic juice, which contains
Digestive system
From the book How to quit smoking 100%, or Love yourself and change your life by Kipnis DavidDigestive system It reacts to smoking primarily with digestive disorders. The production of digestive enzymes decreases, intestinal function and food absorption deteriorate. And then come gastritis, ulcers and
Digestive system
From the book Latin Terminology in the Course of Human Anatomy author Plitnichenko B. G.Digestive system Sublingual salivary gland - glandula salivaria sublingualis Submandibular salivary gland - glandula salivaria submandibularis Parotid salivary gland - glandula salivaria parotis Parotid duct - duсtus parotideus Tooth crown - corona dentis Tooth neck - cervix dentis Tooth root - radix dentis Incisors -
Digestive system
From the book Atlas: human anatomy and physiology. Complete practical guide author Zigalova Elena YurievnaDigestive system The digestive system carries out mechanical and chemical processing of food, the breakdown of nutrients into monomers, the absorption of processed and the release of unprocessed ingredients. The digestive system consists of
Digestive system
From the book How to stop aging and become younger. Result in 17 days by Moreno MikeDigestive System Simply put, digestion is the process of extracting beneficial nutrients from the food we eat. And this process begins even before we lift the first spoon to our mouth - along with the smell of frying bacon sizzling in a frying pan, or
Digestive system
From the book Stevia - a step into immortality author Korodetsky AlexanderDigestive system It has been established that the use of stevia as a food additive improves digestion, activates the activity of the liver and kidneys, normalizes carbohydrate and lipid (fat) metabolism, which has a beneficial effect on the state of the gastrointestinal system.
Digestive system
From the book How to Stay Young and Live Long author Shcherbatykh Yuri ViktorovichDigestive system Everything is in the hands of man. Therefore, they need to be washed as often as possible. Stanislav Jerzy Lec During his life, a person passes through his body tons of different products that interact with our body. Therefore, it is far from indifferent to your health that you
Digestive system
From the book A Healthy Man in Your Home author Zigalova Elena YurievnaDigestive system Human life is impossible without constant receipt of sources of energy and substances for building cells. A person receives all the necessary substances from food, which is digested by the organs of the digestive system. Food is processed
Digestive system
From the book Central Asian Shepherd Dog author Ermakova Svetlana EvgenievnaDigestive system The dog's digestive system consists of the oral cavity, pharynx, esophagus, stomach, small and large intestines, liver and pancreas. The oral cavity is formed by the upper and lower lips, cheeks, gums, teeth, soft and hard palate,
Digestive system
From the book Caucasian Shepherd Dog author Kuropatkina Marina VladimirovnaDigestive system The dog's digestive system consists of the oral cavity, pharynx, esophagus, stomach, small and large intestines, liver and pancreas. The oral cavity consists of the upper and lower jaws, on which the teeth are located. Incisors
- a convenient organ where food is digested, broken down into simple compounds, which are then absorbed by the body and used for its needs. However, tiny organisms - protozoa and sponges - of course, do not have a stomach. Its role is played by a phagosome, also called a digestive vacuole - a vesicle surrounded by a membrane. It forms around a solid particle or cell that the body has decided to consume. A digestive vacuole also appears around the swallowed drop of liquid. The phagosome merges with the lysosome, enzymes are activated and the digestion process begins, which lasts about an hour. During digestion, the environment inside the phagosome changes from acidic to alkaline. Once all the nutrients have been extracted, the undigested food remains are eliminated from the body through the powder or cell membrane.
The digestion of solid food is called phagocytosis, and the digestion of liquid food is called pinocytosis.
Contractile vacuole
Many protists and some sponges have a contractile vacuole. The main function of this organelle is the regulation of osmotic pressure. Through the cell membrane, water enters the cell of a sponge or protozoa, and periodically, at equal intervals of time, the liquid is removed out using a contractile vacuole, which, growing to a certain point, then begins to contract using the elastic bundles present in it.
There is a hypothesis that the contractile vacuole also takes part in cellular respiration.
Vacuole in a plant cell
Plants also have vacuoles. In a young cell, as a rule, there are several small pieces of them, but as the cell grows, they increase and merge into one large vacuole, which can occupy 70-80% of the entire cell. The plant vacuole contains cell sap, which contains minerals, sugars and organic substances. The main function of this organelle is to maintain turgor. Plant vacuoles are also involved in water-salt metabolism, breakdown and absorption of nutrients, and disposal of compounds that can harm the cell. The green parts of plants that are not covered with wood retain their shape thanks to a strong cell wall and vacuoles, which keep the cell shape unchanged and prevent deformation.
The meaning of DIGESTIVE VACUOL in the Encyclopedia of Biology
DIGESTIVE VACULE
Membrane vesicles in the cytoplasm of the cell in which intracellular digestion occurs in protozoa and sponges. Formed by ingestion of solid formed particles or cells (phagocytosis), as well as liquid droplets (pinocytosis). Digestion of food particles by vacuoles is called cyclosis (lasts about 1 hour). During cyclosis, enzymes enter the digestive vacuole and digest the contents, the reaction of which changes from acidic to alkaline. Undigested residues are removed through powder.
Encyclopedia Biology.
2012See also interpretations, synonyms and meanings of the word DIGESTIVE VACULE in Russian in dictionaries, encyclopedias and reference books:
- VACUOL in Medical terms:
(vacuola cellularis, lnh; lat. vacuus empty, hollow) cellular inclusion, which is a bubble, usually with liquid ... - DIGESTIVE in the Big Russian Encyclopedic Dictionary:
DIGESTIVE SYSTEM, a set of digestive organs in animals and humans. In vertebrates it is represented by the oral cavity, pharynx, esophagus, stomach, intestines, as well as ... - VACUOL in the Complete Accented Paradigm according to Zaliznyak:
vacuo"li, vacuo"li, vacuo"li, vacuo"ley, vacuo"li, vacuo"lyam,vacuo"li, vacuo"li,vacuo"liu,vacuo"lya,vacuo"li, ... - VACUOL in the Dictionary for solving and composing scanwords:
Part alive... - VACUOL in the dictionary of Synonyms of the Russian language.
- VACUOL in the New Explanatory Dictionary of the Russian Language by Efremova:
and. cm. … - VACUOL in Ephraim's Explanatory Dictionary:
vacuole cm. … - VACUOL in the New Dictionary of the Russian Language by Efremova:
and. cm. … - VACUOL in the Large Modern Explanatory Dictionary of the Russian Language:
and. cm. … - DIGESTIVE SYSTEM in the Encyclopedia Biology:
, a set of organs involved in digestion (digestive tract and digestive glands). The digestive system of mammals includes the oral cavity. taking over... - CILATES in the Encyclopedia Biology:
, a type of the most complexly organized protozoa. OK. 7 thousand species. They inhabit seas and fresh water bodies, some live in the soil, many... - DIGESTIVE SYSTEM in Medical terms:
(s. digestorium, jna) see Digestive apparatus ... - DIGESTIVE TUBE in Medical terms:
see Digestive tract... - DIGESTIVE CONSTITUTION in Medical terms:
(obsolete; p. digestoria) see Hypersthenic constitution... - HUMAN ANATOMY: DIGESTIVE SYSTEM in Collier's Dictionary.
- COMPARATIVE ANATOMY: DIGESTIVE SYSTEM in Collier's Dictionary.
- BIG jackpot in Quotebook Wiki.
- ARTHOPODAS in the Encyclopedia Biology:
, a type of invertebrate animal. The most numerous of all types of animals (has about 1.5 million species, which is approximately 3/4 of all ... - CHLAMYDOMONAS in the Encyclopedia Biology:
, a genus of green algae. Includes approx. 500 species. Found in fresh water bodies and soil. Single-celled algae oval, round or pear-shaped... - SHOE in the Encyclopedia Biology:
, the simplest type of ciliates. The cell (body) has a spindle-shaped shape, reminiscent of a shoe (hence the name). Covered with many cilia (approx. 15 thousand). Thanks to … - BLUE-GREEN ALGAE in the Encyclopedia Biology:
(cyanobacteria), department of algae. Includes approx. 2 thousand species. Widely distributed in fresh and sea waters, in soil, they often settle there, ... - DIGESTION in Encyclopedia Biology.
- LIVER in Encyclopedia Biology.
- ORGANISM in the Encyclopedia Biology:
, specimen, individual, living being. In a broader sense, it is also any biological system consisting of individual structural... - INSECTS in the Encyclopedia Biology:
, a class of animals belonging to the phylum Arthropods. The most numerous (over 1 million species) group of animals. Known since the Devonian. Length … - LANCELANDS in the Encyclopedia Biology:
, a class of chordates, the only one in the subphylum of the skullless. Includes approx. 30 species living in shallow waters of warm and temperate seas. Peculiarities … - ROUNDWORMS in the Encyclopedia Biology:
(protocavitary worms), a type of invertebrate animal. They probably originated from eyelash worms. The non-segmented body of roundworms is covered with a dense multi-layered cuticle. Eyelash cover... - CELL in the Encyclopedia Biology:
, the basic structural and functional unit of all living organisms. Cells exist in nature as independent single-celled organisms (bacteria, protozoa and... - INTESTINES in Encyclopedia Biology.
- ANIMALS in the Encyclopedia Biology:
, organisms that make up one of the kingdoms of living nature; unlike plants, they use ready-made organic compounds for food (see heterotrophs... - AMOEBA in the Encyclopedia Biology:
, a class of protozoa of the Sarcodaceae type. These are the most simply arranged rhizomes that do not have a shell. Sizes from 20 to 700 microns. ... - CONSTITUTION OF HUMAN in the Explanatory Dictionary of Psychiatric Terms:
(Latin constitutio - construction, organization). A set of morphological and functional characteristics of an organism, formed on the basis of heredity and as a result of long-term influence ... - DIGESTIVE TRACT in Medical terms:
(tubus digestorius, bna; synonym: alimentary canal, gastrointestinal tract, digestive tube, digestive canal) part of the digestive system that has a tubular structure, including the esophagus, ... - HYPERSTHENIC CONSTITUTION in Medical terms:
(p. hypersthenica; syn.: k. picnic, k. digestive obsolete) - K., characterized by a picnic physique combined with cheerfulness, sociability, ... - DIGESTIVE APPARATUS in Medical terms:
(a. digestorius, pna, bna; systema digestorium, pna, jna; synonym: digestive system) a complex of organs providing mechanical and chemical processing of food, absorption ... - INTESTINES in the Big Encyclopedic Dictionary:
the digestive tube in most animals; begins with the oral opening and ends with the anal opening. In humans and animals with a digestive system differentiated into sections... - TREMATODES
(Trematoda), digenetic flukes (Digenea), class of phylum of flatworms. Adult forms parasitize vertebrates and humans, larvae - most... - LIVER in the Great Soviet Encyclopedia, TSB:
a large gland of the animal body, participating in the processes of digestion, metabolism, blood circulation and carrying out specific protective and neutralizing, enzymatic and excretory ... - INTESTINES in the Great Soviet Encyclopedia, TSB.
- AMOEBA in the Great Soviet Encyclopedia, TSB:
(Amoebina), naked amoebas, a detachment of the most simply organized protozoa of the class Sarcodidae. Most live in fresh water bodies, some in the soil; there are parasitic... - PHYSIOLOGICAL DIVISION OF LABOR in the Encyclopedic Dictionary of Brockhaus and Euphron:
Or, more precisely, departures are the basic principle of differentiation of organisms. If the functions of cells in a colony of protozoa (Protozoa) are the same, then these ... - SOLNECHNIKI in the Encyclopedic Dictionary of Brockhaus and Euphron.