The cellular structure of all living organisms have?

As is known, the cellular structure have almost all organisms on the planet.Basically, all cells have the same structure.This is the smallest structural and functional unit of a living organism.Cells may have different functions, and hence the variation in their structure.In many cases, they can act as independent organisms.Cell structure are plants, animals, fungi, bacteria.However, between their structural and functional units, there are some differences.In this article we look at the cellular structure.Grade 8 includes the study of the topic.Therefore, the article will be interesting for students as well as those who are simply interested in biology.This review will be described cellular structure, the cells of different organisms, similarities and differences between them.

history of the theory of cellular structure

People do not always know what it consists of organisms.The fact that all the cells are formed from tissue, became known recently.Science, which studies this - biology.The cell structure of the organism was first described by scientists Matthias Schleiden and Theodor Schwann.This happened in 1838.Then the theory of cellular structure composed of such provisions:

• animals and plants of all kinds are formed of cells;

• they grow via the formation of new cells;

• cell - the smallest unit of life;

• body - a collection of cells.

modern theory includes several other provisions, and a bit more:

• cell can only come from the mother cell;

• multicellular organism is not a simple aggregate of cells, and from the combined in tissues, organs and organ systems;

• cells of all organisms have a similar structure;

• cell - a complex system consisting of smaller functional units;

• cell - the smallest structural unit that can act as an independent body.

structure of cells

Since the cellular structure have almost all living organisms, it is necessary to consider the general characteristics of the structure of that element.First, all cells are divided into prokaryotic and eukaryotic.In the past there core that protects the genetic information recorded on the DNA.In prokaryotic cells, it is not the same, and DNA floats freely.All eukaryotic cells are constructed as follows.They have a shell - the plasma membrane, usually located around the additional protective education.All that is below it, except the core, - a cytoplasm.It consists of hyaloplasm, organelles and inclusions.Hyaloplasm - is the main crystalline substance, which serves as the inner cell environment and fills its space.Organelles - are permanent structures that perform specific functions, ie. E. Provide cellular activity.Inclusion - a non-permanent education, also play a role, but they do so temporarily.

cellular structure of living organisms

Now we list the organelles, which are identical to the cells of every living creature on the planet, except for bacteria.It mitochondria, ribosomes, Golgi apparatus, endoplasmic reticulum, lysosomes, cytoskeleton.For bacteria characterized by only one of these organelles - the ribosome.And now look at the structure and function of each organelle separately.

Mitochondria

They provide intracellular respiration.Mitochondria act as a kind of "power", producing energy which is necessary for the life of the cell, to pass it those or other chemical reactions.They are dvumembrannym organelles, ie they have two protective membranes - external and internal.Beneath them is a matrix - similar hyaloplasm in the cell.Between the outer and inner membranes are formed Christi.This fold inside which are enzymes.These materials are required in order to be able to carry out chemical reactions by which energy is released, the necessary cell.

Ribosomes

They are responsible for protein metabolism, and it is - for the synthesis of this class of substances.Ribosomes are composed of two parts - subunits, large and small.The membrane of the organelle have not.Ribosomal subunits come together just before the process of protein synthesis in the rest of the time they are separated.The substances here are based on the information recorded on the DNA.This information is delivered to the ribosomes by a tRNA as DNA transported here each time it would be impractical and dangerous - too high would be a likelihood of damage.

Golgi apparatus

This organelle is composed of stacks of flat tanks.Function organelle consist in that it collects and modifies various substances and participates in the formation of lysosomes.

endoplasmic reticulum

It is divided into smooth and rough.First constructed of flat tubes.He is responsible for the production in the cell of steroids and lipids.Roughness is so called because the walls of the membranes of which it consists are numerous ribosome.It performs the transport function.Namely it suffers from ribosomal proteins synthesized therein, to the Golgi apparatus.

Lysosomes

They are odnomembrannye organelles that contain enzymes needed for the chemical reactions that occur in the process of intracellular metabolism.The largest number of lysosomes is observed in white blood cells - the cells that perform immune function.This is explained by the fact that they are forced to perform phagocytosis and digest foreign protein, which need a large amount of enzymes.

cytoskeleton

This is the last organelle, which is common to fungi, plants and animals.One of its main functions is to maintain cell shape.It is formed of microtubules and microfilaments.The first is a hollow tube of the protein tubulin.Their presence in the cytoplasm of certain organelles may move in the cell.In addition, the microtubules can also consist of cilia and flagella in unicellular.The second component of the cytoskeleton - microfilaments - consists of contractile proteins actin and myosin.In bacteria, this organelle is usually absent.But some of them are characterized by the presence of the cytoskeleton, but more primitive, arranged not as difficult as in fungi, plants and animals.

organelles of plant cells

cellular structure of plants has some peculiarities.In addition to the above organelles are also present vacuoles and plastids.The former are intended for accumulation therein of substances including unnecessary, as they withdraw from the cell due to the presence of dense membrane wall around often impossible.The fluid which is inside the vacuole, called cell sap.The young plant cells initially have a few small vacuoles, which, as its aging merge into one large.Plastids are divided into three types: chromoplasts, leucoplasts and chromoplasts.The former are characterized by the presence of red, yellow or orange pigment.Chromoplasts in most cases necessary to raise the bright color of pollinating insects or animals that are involved in the spread of the fruits with the seed.It is due to data organelles flowers and fruits have a variety of colors.Chromoplasts can be formed from the chloroplasts, which can be observed in the autumn, when the leaves turn yellow and red shades, as well as during the ripening of the fruit, when gradually disappears completely green.The next type of plastids - leucoplasts - intended for storing substances such as starch, some fats and proteins.Chloroplasts perform photosynthesis process by which plants take for themselves the necessary organic matter.Of the six molecules of carbon dioxide and water as many cell may receive one glucose molecule and six oxygen, which is released into the atmosphere.The chloroplasts are organelles dvumembrannymi.Their matrix contains thylakoids grouped in granite.In these structures, and contain chlorophyll, and are held photosynthesis reaction.Furthermore, in the matrix are also their chloroplast ribosomal RNA, DNA, special enzymes, the starch grains and lipid droplets.Matrix data organelles also called stroma.

Features mushrooms

Cell structure also have these organisms.In ancient times, they were combined into a single kingdom with plants purely by external signs, but with the advent of more advanced science found out that this can not be done.Firstly, fungi, unlike plants are not autotrophs, they can not themselves produce organic substances, only ready-made feed.Secondly, the fungal cells more similar to animal, although it has certain traits plant.Fungal cells, as well as plants, surrounded by a dense wall, but it is not composed of cellulose and chitin.This material is difficult to digest by the body of animals, fungi, and therefore considered to be a heavy meal.Besides organelles, as described above, which are common to all eukaryotes, there is also the vacuole - this is another similarity of fungi with plants.But plastids in cells of the mushroom structure is not observed.Between the wall and the cytoplasmic membrane is lomasoma, the functions of which are still not fully understood.The rest of the structure of the fungal cell resembles an animal.Besides organelles in the cytoplasm as floating such inclusions as fat droplets, glycogen.

Animal cells

They are characterized by all the organelles that were described earlier in this article.In addition, located on top of the plasma membrane glycocalyx - a shell consisting of lipids, polysaccharides and glycoproteins.He is involved in the transport of substances between cells.

kernel

Of course, in addition to general organelles, animal, plant, fungal cells have a nucleus.It is protected by two shells, which have pores.The matrix consists of karyoplasm (nuclear sap), wherein the float chromosome with stored genetic information.Also there nucleoli, which are responsible for the formation of ribosomes and the synthesis of RNA.

Prokaryotes

These include bacteria.Cell structure of bacteria is more primitive.They do not have a nucleus.The cytoplasm contains organelles such as ribosomes.Around the plasma membrane is the cell wall of murein.Most prokaryotes is provided organelles movement - mostly flagella.Around the cell wall may also be located further containment - mucous capsule.Besides the basic DNA molecules in the cytoplasm of bacteria are plasmids in which information is recorded, is responsible for increasing the body's resistance to adverse conditions.

Do all organisms are built from cells?

Some believe that the cellular structure of all living organisms have.But this is not true.There is a kingdom of living organisms such as viruses.They do not consist of cages.This body is represented capsid - protein coat.Inside it is a DNA or RNA, which recorded a small amount of genetic information.Around the capsid protein can also be located lipoprotein called superkapsidom.Viruses can reproduce only within the cells of others.Furthermore, they are capable of crystallization.As you can see, the claim that the cellular structure of all living organisms are incorrect.

Comparison table

After we reviewed the structure of various organisms to summarize.Thus, the cellular structure, the table:

Here, perhaps, and all.We examined the cellular structure of organisms that exist on the planet.