The cells that form the tissues of plants and animals vary considerably in shape, size and internal structure. However, all of them show similarities in the main features of the processes of vital activity, metabolism, in irritability, growth, development, and the ability to change.
Biological transformations occurring in a cell are inextricably linked with those structures of a living cell that are responsible for the performance of a single or other function. Such structures are called organelles.
Cells of all types contain three main, inextricably linked components:
- the structures that form its surface: the outer membrane of the cell, or the cell membrane, or the cytoplasmic membrane;
- cytoplasm with a whole complex of specialized structures - organelles (endoplasmic reticulum, ribosomes, mitochondria and plastids, Golgi complex and lysosomes, cell center), which are constantly present in the cell, and temporary formations called inclusions;
- nucleus - separated from the cytoplasm by a porous membrane and contains nuclear juice, chromatin and nucleolus.
Cell structure
The surface apparatus of the cell (cytoplasmic membrane) of plants and animals has some features.
In unicellular organisms and leukocytes, the outer membrane ensures the penetration of ions, water, and small molecules of other substances into the cell. The process of penetration of solid particles into the cell is called phagocytosis, and the entry of droplets of liquid substances is called pinocytosis.
The outer plasma membrane regulates the exchange of substances between the cell and the external environment.
Eukaryotic cells contain organelles covered with a double membrane - mitochondria and plastids. They contain their own DNA and protein-synthesizing apparatus, multiply by division, that is, they have a certain autonomy in the cell. In addition to ATP, a small amount of protein is synthesized in mitochondria. Plastids are characteristic of plant cells and multiply by division.
| Cell types | The structure and functions of the outer and inner layers of the cell membrane | ||
|---|---|---|---|
| outer layer (chemical composition, functions) |
inner layer - plasma membrane |
||
| chemical composition | functions | ||
| plant cells | Made up of fiber. This layer serves as the framework of the cell and performs a protective function. | Two layers of protein, between them - a layer of lipids | Limits the internal environment of the cell from the external and maintains these differences |
| animal cells | The outer layer (glycocalix) is very thin and elastic. Consists of polysaccharides and proteins. Performs a protective function. | Same | Special enzymes of the plasma membrane regulate the penetration of many ions and molecules into the cell and their release into the external environment. |
Single-membrane organelles include the endoplasmic reticulum, the Golgi complex, lysosomes, various types of vacuoles.
Modern means of research have allowed biologists to establish that, according to the structure of the cell, all living beings should be divided into organisms "non-nuclear" - prokaryotes and "nuclear" - eukaryotes.
Prokaryotic bacteria and blue-green algae, as well as viruses, have only one chromosome, represented by a DNA molecule (less often RNA), located directly in the cytoplasm of the cell.
| Major organoids | Structure | Functions |
|---|---|---|
| Cytoplasm | Internal semi-liquid medium of fine-grained structure. Contains a nucleus and organelles |
|
| EPS - endoplasmic reticulum | The system of membranes in the cytoplasm "forming channels and larger cavities, ER is of 2 types: granular (rough), on which many ribosomes are located, and smooth |
|
| Ribosomes | Small bodies with a diameter of 15-20 mm | Carry out the synthesis of protein molecules, their assembly from amino acids |
| Mitochondria | They have spherical, filiform, oval and other shapes. There are folds inside the mitochondria (length from 0.2 to 0.7 microns). The outer cover of mitochondria consists of 2 membranes: the outer one is smooth, and the inner one forms outgrowths-crosses on which respiratory enzymes are located. |
|
| Plastids - characteristic only of plant cells, there are three types: | double membrane cell organelles | |
| chloroplasts | They are green, oval in shape, limited from the cytoplasm by two three-layer membranes. Inside the chloroplast are the faces where all the chlorophyll is concentrated | Use the light energy of the sun and create organic substances from inorganic |
| chromoplasts | Yellow, orange, red or brown, formed as a result of the accumulation of carotene | Give different parts of plants a red and yellow color |
| leucoplasts | Colorless plastids (found in roots, tubers, bulbs) | They store spare nutrients. |
| Golgi complex | It can have a different shape and consists of cavities delimited by membranes and tubules extending from them with bubbles at the end |
|
| Lysosomes | Round bodies about 1 µm in diameter. They have a membrane (skin) on the surface, inside of which there is a complex of enzymes | Perform a digestive function - digest food particles and remove dead organelles |
| Organelles of cell movement |
|
|
| Cell inclusions | These are non-permanent components of the cell - carbohydrates, fats and proteins. | Spare nutrients used in the life of the cell |
| Cell Center | Consists of two small bodies - centrioles and centrosphere - a compacted area of the cytoplasm | Plays an important role in cell division |
Eukaryotes have a great wealth of organelles, have nuclei containing chromosomes in the form of nucleoproteins (a complex of DNA with a histone protein). Eukaryotes include most modern plants and animals, both unicellular and multicellular.
There are two levels of cellular organization:
- prokaryotic - their organisms are very simply arranged - they are unicellular or colonial forms that make up the kingdom of shotguns, blue-green algae and viruses
- eukaryotic - unicellular colonial and multicellular forms, from protozoa - rhizomes, flagellates, ciliates - to higher plants and animals that make up the kingdom of plants, the kingdom of fungi, the kingdom of animals
| Major organelles | Structure | Functions |
|---|---|---|
| Nucleus of plant and animal cells | Round or oval shape | |
| The nuclear envelope consists of 2 membranes with pores |
|
|
| Nuclear juice (karyoplasm) - a semi-liquid substance | The environment in which the nucleoli and chromosomes are located | |
| Nucleoli are spherical or irregular | They synthesize RNA, which is part of the ribosome | |
| Chromosomes are dense, elongated or filamentous formations that are visible only during cell division. | Contain DNA, which contains hereditary information that is passed down from generation to generation |
All organelles of the cell, despite the peculiarities of their structure and functions, are interconnected and "work" for the cell as a single system in which the cytoplasm is the link.
Special biological objects, occupying an intermediate position between animate and inanimate nature, are viruses discovered in 1892 by D.I. Ivanovsky, they currently constitute the object of a special science - virology.
Viruses reproduce only in the cells of plants, animals and humans, causing various diseases. Viruses have a very simple structure and consist of a nucleic acid (DNA or RNA) and a protein coat. Outside the host cells, the viral particle does not show any vital functions: it does not feed, does not breathe, does not grow, does not multiply.
Lesson type: combined.
Methods: verbal, visual, practical, problem-search.
Lesson Objectives
Educational: to deepen students' knowledge of the structure of eukaryotic cells, to teach how to apply them in practical classes.
Developing: to improve the ability of students to work with didactic material; develop students' thinking by offering tasks for comparing prokaryotic and eukaryotic cells, plant cells and animal cells with the identification of similar and distinctive features.
Equipment: poster "The structure of the cytoplasmic membrane"; task cards; handout (the structure of a prokaryotic cell, a typical plant cell, the structure of an animal cell).
Intersubject communications: botany, zoology, human anatomy and physiology.
Lesson Plan
I. Organizational moment
Check readiness for the lesson.
Checking the list of students.
Presentation of the topic and objectives of the lesson.
II. Learning new material
Division of organisms into pro- and eukaryotes
The shape of the cells is extremely diverse: some are rounded, others look like stars with many rays, others are elongated, etc. Cells are also different in size - from the smallest, hardly distinguishable in a light microscope, to those perfectly visible to the naked eye (for example, fish and frog eggs).
Any unfertilized egg, including giant fossilized dinosaur eggs that are kept in paleontological museums, were also once living cells. However, if we talk about the main elements of the internal structure, all cells are similar to each other.
prokaryotes (from lat. pro- before, before, instead of and Greek. karyon- nucleus) - these are organisms whose cells do not have a nucleus limited by a membrane, i.e. all bacteria, including archaebacteria and cyanobacteria. The total number of species of prokaryotes is about 6000. All the genetic information of a prokaryotic cell (genophore) is contained in a single circular DNA molecule. Mitochondria and chloroplasts are absent, and the functions of respiration or photosynthesis, which provide the cell with energy, are performed by the plasma membrane (Fig. 1). Prokaryotes reproduce without a pronounced sexual process by dividing in two. Prokaryotes are able to carry out a number of specific physiological processes: they fix molecular nitrogen, carry out lactic acid fermentation, decompose wood, and oxidize sulfur and iron.
After an introductory conversation, students consider the structure of a prokaryotic cell, comparing the main features of the structure with the types of eukaryotic cells (Fig. 1).
eukaryotes - These are higher organisms that have a clearly defined nucleus, which is separated from the cytoplasm by a membrane (karyomembrane). Eukaryotes include all higher animals and plants, as well as unicellular and multicellular algae, fungi and protozoa. Nuclear DNA in eukaryotes is enclosed in chromosomes. Eukaryotes have cellular organelles limited by membranes.
Differences between eukaryotes and prokaryotes
- Eukaryotes have a real nucleus: the genetic apparatus of a eukaryotic cell is protected by a shell similar to the shell of the cell itself.
– Organelles included in the cytoplasm are surrounded by a membrane.
The structure of plant and animal cells
The cell of any organism is a system. It consists of three interconnected parts: membrane, nucleus and cytoplasm.
In the study of botany, zoology and human anatomy, you have already become familiar with the structure of various types of cells. Let's briefly review this article.
Exercise 1. Determine from Figure 2 which organisms and tissue types correspond to the cells under the numbers 1-12. What is the reason for their shape?
The structure and functions of organelles of plant and animal cells
Using figures 3 and 4 and using the Biological Encyclopedic Dictionary and textbook, students complete the table comparing animal and plant cells.
Table. The structure and functions of organelles of plant and animal cells
cell organelles |
The structure of organelles |
Function |
Presence of organelles in cells |
|
plants |
animals |
|||
Chloroplast |
It is a type of plastid |
Colors plants green for photosynthesis |
||
leukoplast |
The shell consists of two elementary membranes; internal, growing into the stroma, forms a few thylakoids |
Synthesizes and accumulates starch, oils, proteins |
||
Chromoplast |
Plastids with yellow, orange and red color, the color is due to pigments - carotenoids |
Red, yellow color of autumn leaves, juicy fruits, etc. |
||
Occupies up to 90% of the volume of a mature cell, filled with cell sap |
Maintenance of turgor, accumulation of reserve substances and metabolic products, regulation of osmotic pressure, etc. |
|||
microtubules |
Composed of the protein tubulin, located near the plasma membrane |
Participate in the deposition of cellulose on cell walls, the movement of various organelles in the cytoplasm. During cell division, microtubules form the basis of the division spindle structure. |
||
Plasma membrane (CPM) |
Consists of a lipid bilayer permeated with proteins immersed to various depths |
Barrier, transport of substances, communication between cells |
||
Smooth EPR |
System of flat and branching tubules |
Carries out the synthesis and release of lipids |
||
Rough EPR |
It got its name because of the many ribosomes on its surface. |
Synthesis of proteins, their accumulation and transformation for release from the cell to the outside |
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Surrounded by a double nuclear membrane with pores. The outer nuclear membrane forms a continuous structure with the ER membrane. Contains one or more nucleoli |
Carrier of hereditary information, center of regulation of cell activity |
|||
cell wall |
Composed of long cellulose molecules arranged in bundles called microfibrils |
Outer frame, protective shell |
||
Plasmodesmata |
Tiny cytoplasmic channels that pierce cell walls |
Unite protoplasts of neighboring cells |
||
Mitochondria |
ATP synthesis (energy storage) |
|||
golgi apparatus |
Consists of a stack of flat sacs - cisterns, or dictyosomes |
Synthesis of polysaccharides, formation of CPM and lysosomes |
||
Lysosomes |
intracellular digestion |
|||
Ribosomes |
Composed of two unequal subunits |
Site of protein biosynthesis |
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Cytoplasm |
Consists of water with a large amount of dissolved substances containing glucose, proteins and ions |
It contains other organelles of the cell and all processes of cellular metabolism are carried out. |
||
Microfilaments |
Actin fibers are usually arranged in bundles near the surface of cells |
Involved in cell motility and reshaping |
||
Centrioles |
May be part of the mitotic apparatus of the cell. A diploid cell contains two pairs of centrioles |
Participate in the process of cell division in animals; in zoospores of algae, mosses and in protozoa they form basal bodies of cilia |
||
microvilli |
protrusions of the plasma membrane |
Increase the outer surface of the cell, microvilli together form the border of the cell |
||
conclusions
1. The cell wall, plastids and the central vacuole are inherent only in plant cells.
2. Lysosomes, centrioles, microvilli are present mainly only in the cells of animal organisms.
3. All other organelles are characteristic of both plant and animal cells.
The structure of the cell membrane
The cell membrane is located outside the cell, delimiting the latter from the external or internal environment of the body. It is based on the plasmalemma (cell membrane) and the carbohydrate-protein component.
Cell wall functions:
- maintains the shape of the cell and gives mechanical strength to the cell and the organism as a whole;
- protects the cell from mechanical damage and the ingress of harmful compounds into it;
- performs recognition of molecular signals;
- regulates the exchange of substances between the cell and the environment;
- carries out intercellular interaction in a multicellular organism.
Cell wall function:
- represents an external frame - a protective shell;
- provides transport of substances (water, salts, molecules of many organic substances pass through the cell wall).
The outer layer of animal cells, unlike the cell walls of plants, is very thin and elastic. It is not visible under a light microscope and consists of a variety of polysaccharides and proteins. The surface layer of animal cells is called glycocalyx, performs the function of a direct connection of animal cells with the external environment, with all the substances surrounding it, does not play a supporting role.
Under the glycocalyx of the animal and cell wall of the plant cell, there is a plasma membrane that borders directly on the cytoplasm. The plasma membrane contains proteins and lipids. They are arranged in an orderly manner due to various chemical interactions with each other. Lipid molecules in the plasma membrane are arranged in two rows and form a continuous lipid bilayer. Protein molecules do not form a continuous layer, they are located in the lipid layer, plunging into it at different depths. Molecules of proteins and lipids are mobile.
Functions of the plasma membrane:
- forms a barrier that separates the internal contents of the cell from the external environment;
- provides transport of substances;
- provides communication between cells in the tissues of multicellular organisms.
Entry of substances into the cell
The surface of the cell is not continuous. In the cytoplasmic membrane there are numerous tiny holes - pores through which, with or without the help of special proteins, ions and small molecules can penetrate into the cell. In addition, some ions and small molecules can enter the cell directly through the membrane. The entry of the most important ions and molecules into the cell is not passive diffusion, but active transport, which requires energy. Transport of substances is selective. The selective permeability of the cell membrane is called semipermeability.
way phagocytosis inside the cell enter: large molecules of organic substances, such as proteins, polysaccharides, food particles, bacteria. Phagocytosis is carried out with the participation of the plasma membrane. In the place where the surface of the cell comes into contact with a particle of some dense substance, the membrane flexes, forms a depression and surrounds the particle, which in the "membrane capsule" is immersed inside the cell. A digestive vacuole is formed, and organic substances that have entered the cell are digested in it.
By phagocytosis, amoeba, ciliates, animal and human leukocytes feed. Leukocytes absorb bacteria, as well as a variety of solid particles that accidentally enter the body, thus protecting it from pathogenic bacteria. The cell wall of plants, bacteria and blue-green algae prevents phagocytosis, and therefore this pathway of substances entering the cell is not realized in them.
Liquid droplets containing various substances in a dissolved and suspended state also penetrate into the cell through the plasma membrane. This phenomenon was called pinocytosis. The process of fluid absorption is similar to phagocytosis. A drop of liquid is immersed in the cytoplasm in a "membrane package". Organic substances that enter the cell along with water begin to be digested under the influence of enzymes contained in the cytoplasm. Pinocytosis is widespread in nature and is carried out by the cells of all animals.
III. Consolidation of the studied material
What two large groups are all organisms divided into according to the structure of the nucleus?
What organelles are found only in plant cells?
What organelles are found only in animal cells?
What is the difference between the structure of the cell wall of plants and animals?
What are the two ways substances enter the cell?
What is the importance of phagocytosis for animals?
Organelles, they are also organelles, are the basis for the proper development of the cell. They are permanent, that is, structures that do not disappear anywhere, which have a certain structure, on which the functions they perform directly depend. There are the following types of organelles: two-membrane and one-membrane. The structure and functions of cell organelles deserve special attention for theoretical and, if possible, practical study, since these structures, despite their small size, indistinguishable without a microscope, ensure the maintenance of the viability of all organs without exception and the organism as a whole.
Two-membrane organelles are plastids, the cell nucleus and mitochondria. Single-membrane - organelles of the vacuolar system, namely: eps, lysosomes, Golgi complex (apparatus), various vacuoles. There are also non-membrane organelles - this is the cell center and ribosomes. A common property of membrane types of organelles is that they were formed from biological membranes. The plant cell differs in structure from the animal cell, which is not least facilitated by the processes of photosynthesis. The scheme of photosynthetic processes can be found in the corresponding article. The structure and functions of cell organelles indicate that in order to ensure their smooth operation, it is necessary that each of them individually work without failures.
The cell wall or matrix is composed of cellulose and its related structure, hemicellulose, as well as pectins. Wall functions - protection from negative external influences, support, transport (transfer of nutrients and water from one part of the structural unit to another), buffer.
The nucleus is formed by a double membrane with depressions - pores, nucleoplasm containing chromatin in its composition, nucleoli, in which hereditary information is stored.
A vacuole is nothing more than a fusion of EPS sections surrounded by a specific membrane called a tonoplast that regulates a process called excretion and its reverse - the supply of necessary substances.
EPR is a channel formed by two types of membranes - smooth and rough. The functions that EPR performs are synthesis and transport.
Ribosomes - perform the function of protein synthesis.
The main organelles include: mitochondria, plastids, spherosomes, cytosomes, lysosomes, peroxisomes, antigens and translosomes.
Table. Cell organelles and their functions
This table considers all available cell organelles, both plant and animal.
| Organoid (Organella) | Structure | Functions |
| Cytoplasm | The internal semi-liquid substance, the basis of the cellular environment, is formed by a fine-grained structure. Contains a nucleus and a set of organelles. | Interaction between the nucleus and organelles. Transport of substances. |
| Core | Spherical or oval shape. It is formed by the nuclear envelope, consisting of two membranes with pores. There is a semi-liquid base called karyoplasm or cell sap. Chromatin, or strands of DNA, form dense structures called chromosomes. Nucleoli are the smallest, rounded bodies of the nucleus. |
Regulates all processes of biosynthesis, such as metabolism and energy, carries out the transfer of hereditary information. Karyoplasm limits the nucleus from the cytoplasm, in addition, it makes it possible to exchange directly between the nucleus and the cytoplasm. DNA contains the hereditary information of the cell, so the nucleus is the keeper of all information about the body. In the nucleolus, RNA and proteins are synthesized, from which ribosomes are subsequently formed. |
| cell membrane | The membrane is formed by a double layer of lipids, as well as protein. In plants, the outside is covered with an additional layer of fiber. | Protective, provides the shape of cells and cellular communication, passes the necessary substances into the cell and removes metabolic products. Carries out the processes of phagocytosis and pinocytosis. |
| EPS (smooth and rough) | The endoplasmic reticulum is formed by a system of channels in the cytoplasm. In turn, smooth ER is formed, respectively, by smooth membranes, and rough ER by membranes covered with ribosomes. | Carries out the synthesis of proteins and some other organic substances, and is also the main transport system of the cell. |
| Ribosomes | The processes of the rough membrane of the eps are spherical in shape. | The main function is the synthesis of proteins. |
| Lysosomes | A vesicle surrounded by a membrane. | Digestion in a cell |
| Mitochondria | Covered with outer and inner membranes. The inner membrane has numerous folds and projections called cristae. | Synthesizes ATP molecules. Provides the cell with energy. |
| plastids | Taurus surrounded by a double membrane. There are colorless (leukoplasts) green (chloroplasts) and red, orange, yellow (chromoplasts) | Leukoplasts - accumulate starch. Chloroplasts - participate in the process of photosynthesis. Chromoplasts - Accumulation of carotenoids. |
| Cell Center | Composed of centrioles and microtubules | Participates in the formation of the cytoskeleton. Participation in the process of cell division. |
| Organelles of movement | Cilia, flagella | Carry out various types of movement |
| Golgi complex (apparatus) | Consists of cavities from which bubbles of different sizes separate | Accumulates substances that are synthesized by the cell itself. Use of these substances or release to the external environment. |
The structure of the nucleus - video
Cell- the elementary unit of a living system. Various structures of a living cell, which are responsible for the performance of a particular function, are called organelles, like the organs of the whole organism. Specific functions in the cell are distributed among organelles, intracellular structures that have a certain shape, such as the cell nucleus, mitochondria, etc.
Cell structures:
Cytoplasm. Mandatory part of the cell, enclosed between the plasma membrane and the nucleus. Cytosol is a viscous aqueous solution of various salts and organic substances, permeated with a system of protein filaments - cytoskeletons. Most of the chemical and physiological processes of the cell take place in the cytoplasm. Structure: Cytosol, cytoskeleton. Functions: includes various organelles, the internal environment of the cell
plasma membrane. Each cell of animals, plants, is limited from the environment or other cells by the plasma membrane. The thickness of this membrane is so small (about 10 nm) that it can only be seen with an electron microscope.
Lipids they form a double layer in the membrane, and proteins penetrate its entire thickness, are immersed to different depths in the lipid layer, or are located on the outer and inner surfaces of the membrane. The structure of the membranes of all other organelles is similar to the plasma membrane. Structure: a double layer of lipids, proteins, carbohydrates. Functions: restriction, preservation of the shape of the cell, protection from damage, regulator of the intake and removal of substances.
Lysosomes. Lysosomes are membranous organelles. They have an oval shape and a diameter of 0.5 microns. They contain a set of enzymes that break down organic matter. The membrane of lysosomes is very strong and prevents the penetration of its own enzymes into the cytoplasm of the cell, but if the lysosome is damaged by any external influences, then the entire cell or part of it is destroyed.
Lysosomes are found in all cells of plants, animals and fungi.
Carrying out the digestion of various organic particles, lysosomes provide additional "raw materials" for chemical and energy processes in the cell. During starvation, lysosome cells digest some organelles without killing the cell. Such partial digestion provides the cell with the necessary minimum of nutrients for a while. Sometimes lysosomes digest whole cells and groups of cells, which plays an essential role in the developmental processes in animals. An example is the loss of the tail during the transformation of a tadpole into a frog. Structure: oval-shaped vesicles, membrane outside, enzymes inside. Functions: breakdown of organic substances, destruction of dead organelles, destruction of spent cells.
Golgi complex. The products of biosynthesis entering the lumens of the cavities and tubules of the endoplasmic reticulum are concentrated and transported in the Golgi apparatus. This organelle is 5–10 µm in size.
Structure: cavities surrounded by membranes (vesicles). Functions: accumulation, packaging, excretion of organic substances, formation of lysosomes
Endoplasmic reticulum. The endoplasmic reticulum is a system for the synthesis and transport of organic substances in the cytoplasm of a cell, which is an openwork structure of connected cavities.
A large number of ribosomes are attached to the membranes of the endoplasmic reticulum - the smallest cell organelles that look like a sphere with a diameter of 20 nm. and made up of RNA and protein. Ribosomes are where protein synthesis takes place. Then the newly synthesized proteins enter the system of cavities and tubules, through which they move inside the cell. Cavities, tubules, tubules from membranes, on the surface of ribosome membranes. Functions: synthesis of organic substances with the help of ribosomes, transport of substances.
Ribosomes. Ribosomes are attached to the membranes of the endoplasmic reticulum or are freely located in the cytoplasm, they are arranged in groups, and proteins are synthesized on them. Protein composition, ribosomal RNA Functions: provides protein biosynthesis (assembly of a protein molecule from).
Mitochondria. Mitochondria are energy organelles. The shape of mitochondria is different, they can be the rest, rod-shaped, filamentous with an average diameter of 1 micron. and 7 µm long. The number of mitochondria depends on the functional activity of the cell and can reach tens of thousands in the flying muscles of insects. Mitochondria are externally bounded by an outer membrane, under it is an inner membrane that forms numerous outgrowths - cristae.
Inside the mitochondria are RNA, DNA and ribosomes. Specific enzymes are built into its membranes, with the help of which the energy of food substances is converted into ATP energy in the mitochondria, which is necessary for the life of the cell and the organism as a whole.
Membrane, matrix, outgrowths - cristae. Functions: synthesis of an ATP molecule, synthesis of its own proteins, nucleic acids, carbohydrates, lipids, formation of its own ribosomes.
plastids. Only in the plant cell: leukoplasts, chloroplasts, chromoplasts. Functions: accumulation of reserve organic substances, attraction of pollinating insects, synthesis of ATP and carbohydrates. Chloroplasts are shaped like a disc or a ball with a diameter of 4-6 microns. With a double membrane - external and internal. Inside the chloroplast there are DNA ribosomes and special membrane structures - grana, connected to each other and to the inner membrane of the chloroplast. Each chloroplast has about 50 grains, staggered for better light capture. Chlorophyll is found in the gran membranes, thanks to which the energy of sunlight is converted into the chemical energy of ATP. The energy of ATP is used in chloroplasts for the synthesis of organic compounds, primarily carbohydrates.
Chromoplasts. Red and yellow pigments found in chromoplasts give various parts of the plant their red and yellow color. carrots, tomato fruits.
Leukoplasts are the place of accumulation of a reserve nutrient - starch. There are especially many leukoplasts in the cells of potato tubers. In the light, leukoplasts can turn into chloroplasts (as a result of which potato cells turn green). In autumn, chloroplasts turn into chromoplasts and green leaves and fruits turn yellow and red.
Cell Center. It consists of two cylinders, centrioles, located perpendicular to each other. Functions: support for spindle threads
Cellular inclusions either appear in the cytoplasm or disappear during the life of the cell.
Dense inclusions in the form of granules contain reserve nutrients (starch, proteins, sugars, fats) or cell waste products that cannot yet be removed. All plastids of plant cells have the ability to synthesize and accumulate reserve nutrients. In plant cells, the accumulation of reserve nutrients occurs in vacuoles.
Grains, granules, drops Functions: non-permanent formations that store organic matter and energy
Core. Nuclear envelope of two membranes, nuclear juice, nucleolus. Functions: storage of hereditary information in the cell and its reproduction, RNA synthesis - informational, transport, ribosomal. Spores are located in the nuclear membrane, through which an active exchange of substances between the nucleus and the cytoplasm is carried out. The nucleus stores hereditary information not only about all the features and properties of a given cell, about the processes that should proceed to it (for example, protein synthesis), but also about the characteristics of the organism as a whole. Information is recorded in DNA molecules, which are the main part of chromosomes. The nucleus contains a nucleolus. The nucleus, due to the presence in it of chromosomes containing hereditary information, performs the functions of a center that controls all vital activity and development of the cell.
Mitochondria and plastids have their own circular DNA and small ribosomes, due to which they make part of their proteins themselves (semi-autonomous organelles).
Mitochondria take part in (oxidation of organic substances) - they supply ATP (energy) for the life of the cell, they are the "energy stations of the cell".
Non-membrane organelles
Ribosomes- these are organelles that are engaged. They consist of two subunits, chemically composed of ribosomal RNA and proteins. Subunits are synthesized in the nucleolus. Part of the ribosomes are attached to the ER, this ER is called rough (granular).
Cell Center consists of two centrioles that form the spindle of division during cell division - mitosis and meiosis.
Cilia, flagella serve for movement.
Choose one, the most correct option. The cytoplasm of the cell contains
1) protein filaments
2) cilia and flagella
3) mitochondria
4) cell center and lysosomes
Answer
Establish a correspondence between the functions and organelles of cells: 1) ribosomes, 2) chloroplasts. Write the numbers 1 and 2 in the correct order.
A) located on the granular endoplasmic reticulum
B) protein synthesis
B) photosynthesis
D) consist of two subunits
D) consist of grana with thylakoids
E) form a polysome
Answer
Establish a correspondence between the structure of the cell organoid and the organoid: 1) the Golgi apparatus, 2) the chloroplast. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) two-membrane organelle
B) have their own DNA
B) has a secretory apparatus
D) consists of a membrane, vesicles, cisterns
D) consists of thylakoids gran and stroma
E) single-membrane organelle
Answer
Establish a correspondence between the characteristics and organelles of the cell: 1) chloroplast, 2) endoplasmic reticulum. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) a system of tubules formed by the membrane
B) the organelle is formed by two membranes
B) transport substances
D) synthesizes primary organic matter
D) includes thylakoids
Answer
1. Choose one, the most correct option. Single membrane components of a cell
1) chloroplasts
2) vacuoles
3) cell center
4) ribosomes
Answer
2. Choose three options. What cell organelles are separated from the cytoplasm by a single membrane?
1) Golgi complex
2) mitochondria
3) lysosome
4) endoplasmic reticulum
5) chloroplast
6) ribosome
Answer
All the features below, except for two, can be used to describe the features of the structure and functioning of ribosomes. Identify two signs that “fall out” from the general list, and write down the numbers under which they are indicated.
1) consist of triplets of microtubules
2) participate in the process of protein biosynthesis
3) form a division spindle
4) formed by protein and RNA
5) consist of two subunits
Answer
Choose two correct answers out of five and write down the numbers under which they are indicated in the table. Select two-membrane organelles:
1) lysosome
2) ribosome
3) mitochondrion
4) Golgi apparatus
5) chloroplast
Answer
Choose three correct answers from six and write down the numbers under which they are indicated. Two-membrane organelles of a plant cell are.
1) chromoplasts
2) centrioles
3) leukoplasts
4) ribosomes
5) mitochondria
6) vacuoles
Answer
NUCLEUS1-MITOCHONDRIA1-RIBOSOME1
Analyze the table. For each lettered cell, select the appropriate term from the list provided:
1) core
2) ribosome
3) protein biosynthesis
4) cytoplasm
5) oxidative phosphorylation
6) transcription
7) lysosome
Answer
MITOCHONDRIA2-CHROMOSOME1-RIBOSOMA2 
Analyze the table "Structures of the eukaryotic cell." For each cell marked with a letter, select the appropriate term from the list provided.
1) glycolysis
2) chloroplasts
3) broadcast
4) mitochondria
5) transcription
6) core
7) cytoplasm
8) cell center
Answer
LYSOSOME1-RIBOSOME3-CHLOROPLAST1 
1) Golgi complex
2) carbohydrate synthesis
3) single membrane
4) starch hydrolysis
5) lysosome
6) non-membrane
Answer
LYSOSOME2-CHLOROPLAST2-RIBOSOMA4 
Analyze the table. For each lettered cell, select the appropriate term from the list provided.
1) double membrane
2) endoplasmic reticulum
3) protein biosynthesis
4) cell center
5) non-membrane
6) biosynthesis of carbohydrates
7) single membrane
8) lysosome
Answer
LYSOSOMA3-AG1-CHLOROPLAST3 
Analyze the cell structure table. For each cell marked with a letter, select the appropriate term from the list provided.
1) glycolysis
2) lysosome
3) protein biosynthesis
4) mitochondrion
5) photosynthesis
6) core
7) cytoplasm
8) cell center
Answer
CHLOROPLAST4-AG2-RIBOSOMA5 
Analyze the cell structure table. For each cell marked with a letter, select the appropriate term from the list provided.
1) glucose oxidation
2) ribosome
3) degradation of polymers
4) chloroplast
5) protein synthesis
6) core
7) cytoplasm
8) formation of a fission spindle
Answer
AG3-MITOCHONDRIA3-LYSOSOME4 
Analyze the table "Organoids of the cell." For each cell marked with a letter, select the appropriate term from the list provided.
1) chloroplast
2) endoplasmic reticulum
3) cytoplasm
4) karyoplasm
5) Golgi apparatus
6) biological oxidation
7) transport of substances in the cell
8) glucose synthesis
Answer
1. Choose two correct answers out of five and write down the numbers under which they are indicated in the table. The cytoplasm performs a number of functions in the cell:
1) communicates between the nucleus and organelles
2) acts as a matrix for the synthesis of carbohydrates
3) serves as the location of the nucleus and organelles
4) carries out the transfer of hereditary information
5) serves as the location of chromosomes in eukaryotic cells
Answer
2. Identify two true statements from the general list, and write down the numbers under which they are indicated. Occurs in the cytoplasm
1) ribosome protein synthesis
2) glucose biosynthesis
3) insulin synthesis
4) oxidation of organic substances to inorganic
5) synthesis of ATP molecules
Answer
Choose two correct answers from five and write down the numbers under which they are indicated. Select non-membrane organelles:
1) mitochondrion
2) ribosome
3) core
4) microtubule
5) Golgi apparatus
Answer
The signs listed below, except for two, are used to describe the functions of the depicted cell organoid. Identify two signs that “fall out” from the general list, and write down the numbers under which they are indicated.
1) serves as a power station
2) splits biopolymers into monomers
3) provides packaging of substances from the cell
4) synthesizes and accumulates ATP molecules
5) participates in biological oxidation
Answer
Establish a correspondence between the structure of the organoid and its type: 1) cell center, 2) ribosome
A) consists of two perpendicularly arranged cylinders
B) consists of two subunits
B) made up of microtubules
D) contains proteins that ensure the movement of chromosomes
D) contains proteins and nucleic acid
Answer
Establish the sequence of arrangement of structures in the eukaryotic cell of a plant (starting from the outside)
1) plasma membrane
2) cell wall
3) core
4) cytoplasm
5) chromosomes
Answer
Choose three options. How are mitochondria different from lysosomes?
1) have outer and inner membranes
2) have numerous outgrowths - cristae
3) participate in the processes of energy release
4) in them pyruvic acid is oxidized to carbon dioxide and water
5) in them, biopolymers are broken down to monomers
6) participate in metabolism
Answer
1. Establish a correspondence between the characteristics of a cell organoid and its type: 1) mitochondrion, 2) lysosome. Write the numbers 1 and 2 in the correct order.
A) single membrane organelle
B) internal content - matrix
D) the presence of cristae
D) semi-autonomous organoid
Answer
2. Establish a correspondence between the characteristics and organelles of the cell: 1) mitochondrion, 2) lysosome. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) hydrolytic cleavage of biopolymers
B) oxidative phosphorylation
B) single-membrane organelle
D) the presence of cristae
E) the formation of the digestive vacuole in animals
Answer
3. Establish a correspondence between the trait and the cell organoid for which it is characteristic: 1) lysosome, 2) mitochondria. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) the presence of two membranes
B) energy storage in ATP
C) the presence of hydrolytic enzymes
D) digestion of cell organelles
D) the formation of digestive vacuoles in protozoa
E) the breakdown of organic substances to carbon dioxide and water
Answer
Establish a correspondence between the cell organoid: 1) cell center, 2) contractile vacuole, 3) mitochondria. Write the numbers 1-3 in the correct order.
A) is involved in cell division
B) ATP synthesis
B) excretion of excess fluid
D) "cellular respiration"
E) maintaining a constant cell volume
E) participates in the development of flagella and cilia
Answer
1. Establish a correspondence between the name of organelles and the presence or absence of a cell membrane in them: 1) membrane, 2) non-membrane. Write the numbers 1 and 2 in the correct order.
A) vacuoles
B) lysosomes
B) cell center
D) ribosomes
D) plastids
E) Golgi apparatus
Answer
2. Establish a correspondence between cell organelles and their groups: 1) membrane, 2) non-membrane. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) mitochondria
B) ribosomes
B) centrioles
D) golgi apparatus
D) endoplasmic reticulum
E) microtubules
Answer
3. Which three of the listed organelles are membranous?
1) lysosomes
2) centrioles
3) ribosomes
4) microtubules
5) vacuoles
6) leukoplasts
Answer
1. All of the cell structures listed below, except for two, do not contain DNA. Identify two cell structures that "fall out" from the general list, and write down the numbers under which they are indicated.
1) ribosomes
2) Golgi complex
3) cell center
4) mitochondria
5) plastids
Answer
2. Select three cell organelles containing hereditary information.
1) core
2) lysosomes
3) Golgi apparatus
4) ribosomes
5) mitochondria
6) chloroplasts
Answer
3. Choose two correct answers out of five. In what structures of the eukaryotic cell are DNA molecules localized?
1) cytoplasm
2) core
3) mitochondria
4) ribosomes
5) lysosomes
Answer
Choose one, the most correct option. Where in the cell are ribosomes other than ER
1) in the centrioles of the cell center
2) in the Golgi apparatus
3) in mitochondria
4) in lysosomes
Answer
What are the features of the structure and functions of ribosomes? Choose the three correct options.
1) have one membrane
2) consist of DNA molecules
3) break down organic matter
4) consist of large and small particles
5) participate in the process of protein biosynthesis
6) consist of RNA and protein
Answer
Choose three correct answers from six and write down the numbers under which they are indicated. The nucleus of a eukaryotic cell contains
1) chromatin
2) cell center
3) Golgi apparatus
4) nucleolus
5) cytoplasm
6) karyoplasm
Answer
Choose three correct answers from six and write down the numbers under which they are indicated. What processes take place in the cell nucleus?
1) the formation of a fission spindle
2) formation of lysosomes
3) duplication of DNA molecules
4) synthesis of mRNA molecules
5) formation of mitochondria
6) formation of ribosome subunits
Answer
Establish a correspondence between the cell organoid and the type of structure to which it belongs: 1) single-membrane, 2) two-membrane. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) lysosome
B) chloroplast
B) mitochondrion
D) EPS
D) golgi apparatus
Answer
Establish a correspondence between the characteristics and organelles: 1) chloroplast, 2) mitochondria. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) the presence of stacks of grains
B) carbohydrate synthesis
C) dissimilation reactions
D) transport of electrons excited by photons
D) synthesis of organic substances from inorganic
E) the presence of numerous cristae
Answer
All of the features listed below, except for two, can be used to describe the cell organoid shown in the figure. Identify two signs that “fall out” from the general list, and write down the numbers under which they are indicated.
1) single-membrane organoid
2) contains fragments of ribosomes
3) the shell is riddled with pores
4) contains DNA molecules
5) contains mitochondria
Answer
The terms listed below, except for two, are used to characterize the cell organoid, indicated in the figure by a question mark. Identify two terms that "fall out" from the general list, and write down the numbers under which they are indicated.
1) membrane organoid
2) replication
3) divergence of chromosomes
4) centrioles
5) division spindle
Answer
Establish a correspondence between the characteristics of the cell organoid and its type: 1) cell center, 2) endoplasmic reticulum. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) transport organic matter
B) forms a spindle of division
B) consists of two centrioles
D) single-membrane organoid
D) contains ribosomes
E) non-membrane organelle
Answer
1. Establish a correspondence between the characteristics and organelles of the cell: 1) nucleus, 2) mitochondria. Write down the numbers 1 and 2 in the order corresponding to the numbers.
A) a closed DNA molecule
B) oxidative enzymes on cristae
C) internal contents - karyoplasm
D) linear chromosomes
E) the presence of chromatin in the interphase
E) folded inner membrane
Answer
2. Establish a correspondence between the characteristics and organelles of cells: 1) nucleus, 2) mitochondria. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) is the site of ATP synthesis
B) is responsible for storing the genetic information of the cell
B) contains circular DNA
D) has cristae
D) has one or more nucleoli
Answer
Establish a correspondence between the signs and organelles of the cell: 1) lysosome, 2) ribosome. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) consists of two subunits
B) is a single-membrane structure
C) participates in the synthesis of the polypeptide chain
D) contains hydrolytic enzymes
D) is located on the membrane of the endoplasmic reticulum
E) converts polymers into monomers
Answer
Establish a correspondence between the characteristics and cellular organelles: 1) mitochondrion, 2) ribosome. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) non-membrane organelle
B) the presence of its own DNA
C) function - protein biosynthesis
D) consists of large and small subunits
D) the presence of cristae
E) semi-autonomous organoid
Answer
All the signs listed below, except for two, are used to describe the structure of the cell shown in the figure. Identify two signs that “fall out” from the general list, and write down the numbers under which they are indicated.
1) consists of RNA and proteins
2) consists of three subunits
3) synthesized in hyaloplasm
4) carries out protein synthesis
5) can be attached to the EPS membrane
Answer
© D.V. Pozdnyakov, 2009-2019
