What are the similarities and differences between plant cells? Similarities and differences in the structure of cells of plants, animals, fungi
The cell is unified system, which consists of naturally interconnected elements and has a complex structure. It is endowed with the ability for self-renewal, reproduction, and self-regulation.
What is a cell
All cells contain a cell membrane that surrounds its internal contents. It includes the nucleus, which performs the function of the brain and controls all processes occurring in it, and the cytoplasm, which occupies the entire space of the cell without the nucleus. This zone consists of a liquid called matrix or hyaloplasm and organelles (single and double membrane).
An organelle is a cell structure that performs specific functions. Without them, the cell will not be able to function normally.
The energy function is performed by mitochondria, which indicate the production of energy called ATP. The plant cell also contains two-membrane organelles - chloroplasts, the main function of which is photosynthesis. With their help, plants produce starch.
Another very large organelle of a plant cell is the vacuole, which contains juice, reserve nutrients, which imparts color to plant components and can also act as a garbage collector.
The main organelles also include the endoplasmic reticulum - a system of channels that delimit all organelles, essentially its framework. There are two types of network - rough (granular) and smooth (agranular). On the rough surface there are ribosomes that perform the function of protein formation. Smooth - responsible for lipid synthesis.
A cell is a structural and functional unit of a living organism that carries genetic information, provides metabolic processes, and is capable of regeneration and self-reproduction.
There are unicellular individuals and developed multicellular animals and plants. Their vital activity is ensured by the work of organs that are built from different tissues. Tissue, in turn, is represented by a collection of cells similar in structure and functions.
Cells of different organisms have their own characteristic properties and structure, but there are common components inherent in all cells: both plant and animal.
Organelles common to all cell types
Core- one of the important components of the cell, contains genetic information and ensures its transmission to descendants. It is surrounded by a double membrane, which isolates it from the cytoplasm.
Cytoplasm- a viscous transparent medium that fills the cell. All organelles are located in the cytoplasm. The cytoplasm consists of a system of microtubules, which ensures the precise movement of all organelles. It also controls the transport of synthesized substances.
Cell membrane- a membrane that separates the cell from external environment, ensures the transport of substances into the cell and the removal of products of synthesis or vital activity.
Endoplasmic reticulum– a membrane organelle, consists of cisterns and tubules, on the surface of which ribosomes are synthesized (granular EPS). Places where there are no ribosomes form the smooth endoplasmic reticulum. The granular and agranular network are not delimited, but pass into each other and connect to the core shell.
Golgi complex- a stack of tanks, flattened in the center and expanded at the periphery. Designed to complete the synthesis of proteins and their further transport from the cell; together with EPS, it forms lysosomes.
Mitochondria– double-membrane organelles, the inner membrane forms protrusions into the cell – cristae. Responsible for ATP synthesis and energy metabolism. Performs respiratory function(absorbing oxygen and releasing CO 2).
Ribosomes– are responsible for protein synthesis; small and large subunits are distinguished in their structure.
Lysosomes– carry out intracellular digestion due to the content of hydrolytic enzymes. Break down trapped foreign substances.
In both plant and animal cells, in addition to organelles, there are unstable structures - inclusions. They appear when metabolic processes in the cell increase. They perform a nutritional function and contain:
- Starch grains in plants, and glycogen in animals;
- proteins;
- Lipids are high-energy compounds that are more valuable than carbohydrates and proteins.
There are inclusions that do not play a role in energy metabolism; they contain waste products of the cell. In the glandular cells of animals, inclusions accumulate secretions.
Organelles unique to plant cells
Animal cells, unlike plant cells, do not contain vacuoles, plastids, or a cell wall.
Cell wall is formed from the cell plate, forming the primary and secondary cell walls.
The primary cell wall is found in undifferentiated cells. During maturation, a secondary membrane is formed between the membrane and the primary cell wall. In its structure it is similar to the primary one, only it has more cellulose and less water.
The secondary cell wall is equipped with many pores. A pore is a place where there is no secondary wall between the primary shell and the membrane. The pores are located in pairs in adjacent cells. Cells located nearby communicate with each other by plasmodesmata - this is a channel that is a strand of cytoplasm lined with plasmolemma. Through it, cells exchange synthesized products.
Functions of the cell wall:
- Maintaining cell turgor.
- Gives shape to cells, acting as a skeleton.
- Accumulates nutritious foods.
- Protects from external influences.
Vacuoles– organelles filled with cell sap are involved in the digestion of organic substances (similar to lysosomes animal cell). They are formed through the joint work of the ER and the Golgi complex. First, several vacuoles form and function; during cell aging, they merge into one central vacuole.
Plastids- autonomous double-membrane organelles, the inner shell has outgrowths - lamellae. All plastids are divided into three types:
- Leukoplasts– non-pigmented formations, capable of storing starch, proteins, lipids;
- chloroplasts– green plastids, contain the pigment chlorophyll, capable of photosynthesis;
- chromoplasts– orange crystals due to the presence of carotene pigment.
Organelles unique to animal cells
The difference between a plant cell and an animal cell is the absence of a centriole, a three-layer membrane.
Centrioles– paired organelles located near the nucleus. They take part in the formation of the spindle and contribute to the uniform divergence of chromosomes to different poles of the cell.
Plasma membrane— animal cells are characterized by a three-layer, durable membrane, built from lipids and proteins.
Comparative characteristics of plant and animal cells
| Comparison chart of animal and plant cells | ||
|---|---|---|
| Properties | plant cell | animal cell |
| Organelle structure | Membrane | |
| Core | Formed, with a set of chromosomes | |
| Division | Reproduction of somatic cells through mitosis | |
| Organoids | Similar set of organelles | |
| Cell wall | + | - |
| Plastids | + | - |
| Centrioles | - | + |
| Power type | Autotrophic | Heterotrophic |
| Energy synthesis | With the help of mitochondria and chloroplasts | Only with the help of mitochondria |
| Metabolism | The advantage of anabolism over catabolism | Catabolism exceeds synthesis of substances |
| Inclusions | Nutrients (starch), salts | Glycogen, proteins, lipids, carbohydrates, salts |
| Cilia | Rarely | Eat |
Thanks to chloroplasts, plant cells carry out the processes of photosynthesis - convert the energy of the sun into organic substances; animal cells are not capable of this.
Mitotic division of a plant occurs predominantly in the meristem, characterized by the presence of an additional stage - preprophase; in the animal body, mitosis is inherent in all cells.
The sizes of individual plant cells (about 50 microns) exceed the sizes of animal cells (about 20 microns).
The relationship between plant cells is carried out through plasmodesmata, and in animals - through desmosomes.
Vacuoles in a plant cell occupy most of its volume; in animals they are small formations in small quantities.
The cell wall of plants is made of cellulose and pectin; in animals, the membrane consists of phospholipids.
Plants are not able to actively move, so they have adapted to an autotrophic method of nutrition, independently synthesizing all the necessary nutrients from inorganic compounds.
Animals are heterotrophs and use exogenous organic substances.
The similarity in the structure and functionality of plant and animal cells indicates the unity of their origin and belonging to eukaryotes. Their distinctive features conditioned in different ways life and nutrition.
At the heart of diversity organic world lies the basic unit - the living cell. According to the current scientific concept, life began with nuclear-free prokaryotes, which, due to changes in external conditions and improvement of internal processes, eventually evolved into eukaryotes. Such conclusions were drawn, including from the results of studying the cells of modern prokaryotes and eukaryotes. Scientists have established a significant similarity between these biological objects. The similarity between animal cells and bacteria lies in the fact that they have the same process of transmitting hereditary information, although the organelles (structural parts) have differences in both composition and functioning mechanisms.
Animals and plants are multicellular eukaryotic organisms. This means that all the tissues of their organisms consist of living eukaryotes. Despite the fact that all eukaryotes have prokaryotic symbionts, symbionts are not considered as part of their organisms, but have a separate classification.
Bacteria are unicellular organisms that consist of a single prokaryotic cell. There are many types of prokaryotic organisms that live in colonies, but colonies do not become multicellular creatures.
Animals reach truly enormous sizes, while the largest bacterium is not even visible to the naked eye. And yet, the main driving processes in these organisms have noticeable similarities.
The same structural elements of animal and bacterial cells:
- cell membrane;
- cytoplasm;
- ribosomes;
- DNA is the carrier of hereditary information;
- organelles for spatial movement (flagella, cilia, etc.).
These are the main details that make it possible to isolate the cellular space from the outside world, create an environment for metabolism in the cell and transmit hereditary information during reproduction.
In addition to these organelles, eukaryotic units of animals contain:
- nucleus (structure for storing DNA);
- desmosomes, which provide communication between eukaryotes, which makes it possible to form multicellular organisms;
- centrioles (needed for the division process);
- mitochondria (provide energy);
- lysosomes (break down organic matter).
There are a number of other organelles that synthesize complex proteins inside the cellular space, transport these proteins, and also maintain the cell in a tense state. Bacteria do not need these functions.
Most animal organelles (cellular units) arose as a result of the increased needs of a large eukaryote. In comparison, the prokaryotic monad is practically autonomous, and it does not need to create additional functionality to overcome additional difficulties associated with the overall complexity of the system.
Key Similarities
In addition to the differences, there are also significant similarities that confirm the relatedness of all living organisms, including animal cells and bacteria.
Cell membrane
This organelle is present in prokaryotic and eukaryotic biota (including plants and fungi). It determines the spatial configuration of the cell. It consists of proteins and lipids, thanks to which the transport of necessary substances and the transport of waste products is carried out. The cell membranes of nuclear and non-nuclear creatures may consist of proteins and lipids of different structures, but the principle of construction is always the same.
Cytoplasm
The internal environment of a living cell unit of bacteria, animals, plants and fungi. The similarity lies in the common features of the cytoplasm for all organisms - the combination of structural elements into one whole and aqueous composition. Water is the main component of the cytoplasm. Various mineral salts can be dissolved in water, organic compounds, glucose, but without water the cytoplasm is impossible.
Ribosome
An organelle found in the cells of bacteria, plants, animals and fungi that synthesizes proteins from amino acids using messenger RNA (mRNA) data. The mechanism of protein translation (synthesis) by ribosomes in eukaryotic units and in prokaryotic biota has similarities at almost all stages.
Carriers of hereditary information
In animals, plants and fungi in eukaryotic units, hereditary information is stored in DNA molecules, which are packaged in a nucleoprotein structure - a chromosome.
In prokaryotic biota, information about protein structures is also stored in DNA, but they do not need to be packaged into chromosomes. DNA is presented in the form of a circular macromolecule, which resides freely in the cytoplasm.
Moving and securing in space
Despite the fact that organelles of eukaryotic and prokaryotic structures have similarities in names (flagella, villi, cilia, etc.), they differ significantly in their structure. For example, a bacterial flagellum always rotates around its axis, while eukaryotic cells, if they have flagella, move the cell unit by bending along its entire length.
The general similarities between nuclear-free and nuclear organisms indicate the common nature of these living cells, but there are many differences between these two forms of organic life. Much more than similarities. Almost all vital processes occur differently in these cells.
Similarities and differences in the structure of cells of plants, animals and fungi
Similarities in the structure of eukaryotic cells.
Now it is impossible to say with complete certainty when and how life arose on Earth. We also do not know exactly how the first living creatures on Earth ate: autotrophic or heterotrophic. But at present, representatives of several kingdoms of living beings coexist peacefully on our planet. Despite the great difference in structure and lifestyle, it is obvious that there are more similarities between them than differences, and they all probably have common ancestors who lived in the distant Archean era. The presence of common “grandfathers” and “grandmothers” is evidenced by a number of common characteristics in eukaryotic cells: protozoa, plants, fungi and animals. These signs include:
General plan of the cell structure: the presence of a cell membrane, cytoplasm, nucleus, organelles;
- fundamental similarity of metabolic and energy processes in the cell;
- coding of hereditary information using nucleic acids;
- unity chemical composition cells;
- similar processes of cell division.
Differences in the structure of plant and animal cells.
In the process of evolution, due to the unequal conditions of existence of cells of representatives of different kingdoms of living beings, many differences arose. Let's compare the structure and vital activity of plant and animal cells (Table 4).
The main difference between the cells of these two kingdoms is the way they are nourished. Plant cells containing chloroplasts are autotrophs, that is, they themselves synthesize the organic substances necessary for life using light energy during the process of photosynthesis. Animal cells are heterotrophs, i.e., the source of carbon for the synthesis of their own organic substances is organic substances supplied with food. These same nutrients, such as carbohydrates, serve as a source of energy for animals. There are exceptions, such as green flagellates, which are capable of photosynthesis in the light and feed on ready-made food in the dark. organic substances. To ensure photosynthesis, plant cells contain plastids that carry chlorophyll and other pigments.
Since a plant cell has a cell wall that protects its contents and ensures its constant shape, when dividing between daughter cells, a partition is formed, and an animal cell, which does not have such a wall, divides to form a constriction.
Features of fungal cells.
Thus, the separation of fungi into an independent kingdom, numbering more than 100 thousand species, is absolutely justified. Mushrooms originate either from ancient filamentous algae that have lost chlorophyll, i.e., from plants, or from some ancient heterotrophs unknown to us, i.e., animals.
1. How does a plant cell differ from an animal cell?
2. What are the differences in the division of plant and animal cells?
3. Why are mushrooms separated into an independent kingdom?
4. What do they have in common and what differences in structure and life can be identified by comparing mushrooms with plants and animals?
5. Based on what features can we assume that all eukaryotes had common ancestors?
Kamensky A. A., Kriksunov E. V., Pasechnik V. V. Biology 10th grade
Submitted by readers from the website
According to their structure, the cells of all living organisms can be divided into two large sections: non-nuclear and nuclear organisms.
In order to compare the structure of plant and animal cells, it should be said that both of these structures belong to the superkingdom of eukaryotes, which means they contain a membrane membrane, a morphologically shaped nucleus and organelles for various purposes.
In contact with
Classmates
| Vegetable | Animal | |
| Nutrition method | Autotrophic | Heterotrophic |
| Cell wall | It is located outside and is represented by a cellulose shell. Does not change its shape | Called glycocalyx, it is a thin layer of cells of protein and carbohydrate nature. The structure can change its shape. |
| Cell center | No. Can only be found in lower plants | Eat |
| Division | A partition is formed between the daughter structures | A constriction is formed between the daughter structures |
| Storage carbohydrate | Starch | Glycogen |
| Plastids | Chloroplasts, chromoplasts, leucoplasts; differ from each other depending on color | No |
| Vacuoles | Large cavities that are filled with cell sap. Contain a large number of nutrients. Provide turgor pressure. There are relatively few of them in the cell. | Numerous small digestive, some contractile. The structure is different with plant vacuoles. |
Features of the structure of a plant cell:
Features of the structure of an animal cell:
Brief comparison of plant and animal cells
What follows from this
- The fundamental similarity in the structural features and molecular composition of plant and animal cells indicates the relationship and unity of their origin, most likely from unicellular aquatic organisms.
- Both species contain many elements of the Periodic Table, which mainly exist in the form of complex compounds of inorganic and organic nature.
- However, what is different is that in the process of evolution these two types of cells have moved far away from each other, because from various adverse environmental influences they have absolutely different ways protection and also have different feeding methods from each other.
- A plant cell is mainly distinguished from an animal cell by its strong shell, consisting of cellulose; special organelles - chloroplasts with chlorophyll molecules in their composition, with the help of which we carry out photosynthesis; and well-developed vacuoles with a supply of nutrients.
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