The body consists of many living organisms from tissues.The exceptions are all unicellular and multicellular some, for example, lower plants, which includes algae and lichens.In this article we will look at types of fabrics.Biology studies the subject, namely its section - histology.The title of this industry is derived from the Greek words "fabric" and "knowledge."There are many kinds of fabrics.Biology studies and plant and animal.They have significant differences.Fabrics, types of tissue biology studies for a long time.For the first time they were described even by ancient scholars such as Aristotle and Avicenna.Fabrics kinds of fabrics continues to study biology and then - in the nineteenth century, they examined such well-known scientists as Moldengauer, Mirbel, Hartig and others.With their participation, the discovery of new types of cell populations studied their function.
kinds of fabrics - biology
First of all, it should be noted that the tissues which are peculiar plants are not typical for the animals.Therefore types of tissue biology can be divided into two major groups: plants and animals.Both combine a large number of species.These we shall proceed to discuss.
Kinds of animal tissues
begin with, that is closer to us.Since we belong to the animal kingdom, our body is composed of fabrics, varieties of which will now be described.Types of animal tissues can be grouped into four broad groups: epithelial, muscle, connective and nervous.The first three are divided into a plurality of species.Only the last group is represented by only one type.Next, consider all kinds of fabrics, structure and functions which are characteristic of them in order.
Nervous tissue
Since it is only one species, we begin with it.The cells of this tissue are called neurons.Each of them consists of a body, the dendrites and the axon.Last - this processes in which an electrical pulse is transmitted from cell to cell.Axon from one neuron - it's a long process, several dendrites, they are smaller than the first.In the body of the cell is the nucleus.Furthermore, in the cytoplasm are located so-called bull Nissl - analogue endoplasmic retikulluma mitochondria that produce energy, and neyrotrubochki that participate in the conduction of an impulse from one cell to another.Depending on their functions, neurons are divided into several types.The first type - sensory, or afferent.They conduct impulses from the sense organs to the brain.The second type of neuron - associative, or switching.They analyze the information received from the senses and generate a return pulse.Such types of neurons found in the brain and spinal cord.Last version - motor or afferent.They carried the momentum from the associative neurons to organs.Also in the neural tissue have intercellular substance.It performs a very important function, namely neurons provides a fixed location in space, is involved in the removal of unwanted substances from the cell.
epithelial
These are the kinds of tissues, cells are tightly adjacent to each other.They can have different shapes, but always located close.All the different types of tissue of this group are similar and that the intercellular substance therein is small.It basically presented as a liquid, in some cases it may not be.This kind of body tissues, which provide protection, as well as perform the secretory function.This group includes several varieties.It is a flat, cylindrical, cubic, touch, ciliated and glandular epithelium.From the name of each can be understood from the cells which form they are composed.Different types of epithelial tissues are different and its location in the body.Thus, the cavity is lined with flat upper digestive tract - oral cavity and esophagus.Cylindrical epithelium is in the stomach and intestines.Cubic can be found in the renal tubules.Touch lines the nasal cavity, it villi are special, providing the perception of odors.The cells are ciliated epithelium, as is clear from its name, possess cytoplasmic cilia.This type of tissue lining the airways, which are below the nasal cavity.Cilia, who has every cell, perform a cleansing function - they are somewhat filtered air that passes through the bodies, nestled in this kind of epithelium.And the last group of this kind of tissue - glandular epithelium.Its cells perform secretory function.They are in the prostate as well as in a cavity of certain organs such as the stomach.This type of epithelium cells produce hormones earwax, gastric juice, milk, sebum and many other substances.
Muscle tissue
This group is divided into three types.The muscle is smooth, striated and heart.All muscle tissue like that are composed of long cells - fiber, they contain a very large number of mitochondria, as they need a lot of energy for movement.Smooth muscle tissue lines the cavity of the internal organs.Reduction of muscle we can not control themselves, as they are innervated by the autonomic nervous system.Cells striated muscle tissues are characterized in that they contain more mitochondria than in the first.This is because it requires more energy.Striated muscle is able to decline much faster than smooth.Because it consists skeletal muscle.They are innervated by the somatic nervous system, so we can consciously control them.Muscle tissue heart combines some characteristics of the first two.It is also capable of actively and rapidly reduced, as a striated, but is innervated by the autonomic nervous system, as well as smooth.
connecting tissue types and their functions
All fabrics in this group are characterized by a large number of intercellular substance.In some cases it appears in the liquid aggregate state, in some - in liquid, sometimes - as an amorphous mass.This group includes seven types.It is dense and loose fiber, bone, cartilage, reticular, fat, blood.The first type is dominated by fiber.It is located around the internal organs.Its function is to give them flexibility and protection.The loose fibrous tissue amorphous mass dominates the fibers themselves.It fills the interstices between the internal organs, while the dense fibrous forms only original envelope around the latter.It also plays a protective role.Bone and cartilage tissue forming the skeleton.It performs a supporting function in the body and partially protective.The cells and the intercellular substance bone predominate inorganic substances, mainly calcium compounds and phosphates.Data exchange of substances between the skeleton and blood regulate hormones such as calcitonin and paratireotropin.First support normal bone part in the transformation of phosphorus and calcium ions into organic compounds, is stored in the skeleton.A second, conversely, lack of these ions in the blood stimulates their receipt of skeletal tissue.
blood contains a lot of liquid intercellular substance, it is called a plasma.Her cells rather svoebrazny.They are divided into three types: platelets, erythrocytes and leukocytes.The first are responsible for blood clotting.During this process, a small blood clot formed, which prevents further blood loss.The erythrocytes are responsible for oxygen transport through the body and providing them all tissues and organs.They may be aglyutinogeny that there are two types - A and B. The blood plasma may aglyutininov content of alpha or beta.They are antibodies aglyutinogenam.For these substances and grouping.The first group of erythrocytes aglyutinogenov not observed, and the plasma are aglyutininy two species at once.The second group has aglyutinogenom aglyutininom A and beta.Third - The alpha.In the fourth plasma have aglyutininov but erythrocytes are aglyutinogeny both A and B. If A is found in alpha or beta occurs so-called agglutination reaction, whereby the red blood cells die and form clots.This can happen if blood transfusion nonconforming groups.Given that the transfusion used only red blood cells (plasma is eliminated at any stage of the processing of donated blood), then the person with the first group can be poured only the blood of his own group, the second - the blood of the first and second group, the third - the first and the third group,Fourth - any group.
also on erythrocyte antigens may be in D, which determines the Rh factor, if present, the latter is positive if no - no.Lymphocytes are responsible for immunity.They are divided into two main groups: B lymphocytes and T lymphocytes.First produced in the bone marrow, the second - in the thymus (a gland located behind the breastbone).T-lymphocytes are classified into T inducers of T-helpers and T-suppressors.Reticular connective tissue is composed of a large number of intercellular substance and stem cells.Of these blood cells are formed.This tissue is the basis of bone marrow and other organs of hematopoiesis.There is also a fatty tissue, the cells of which contain lipids.It performs a backup, heat insulation and sometimes protective.
How are the plants?
These organisms, like animals, are composed of aggregates of cells and intercellular substance.Types of plant tissues, and we will describe further.All of them are divided into several large groups.This is an educational, coating, conductive, mechanical and basic.Types of plant tissues are numerous, as to each group owns several.
Educational
They are apical, lateral, and intercalary wound.Their main function - to ensure the growth of the plants.They consist of small cells that are actively dividing, and then differentiate to form any other type of tissue.Apical are at the tips of stems and roots, side - inside the stem, under the cover, intervening - in the grounds of interstices, wound - at the site of injury.
Cover
They are characterized by thick cell walls composed of cellulose.They play a protective role.There are three types: the epidermis, Cork, Cork.The first covers all parts of the plant.She may have a protective waxy coating, as are her hairs, stomata, cuticle pores.Cork characterized in that it has no pores at all other characteristics it is similar to the epidermis.Stopper - coating is dead tissue that forms the bark of trees.
Conductive
These fabrics come in two varieties: xylem and phloem.Their function - transport of dissolved substances from the root to other organs and vice versa.Xylem is formed of vascular formed dead cells with hard shells, no cross membranes.They transport the fluid upwards.Phloem - sieve tubes - live cells, which do not have nuclei.The transverse webs have large pores.With the variety of plant tissues substances dissolved in the water transported downward.
Mechanical
They also come in two types: it collenchyma and sclerenchyma.Their main task - ensuring the strength of all the organs.Collenchyma presented by living cells with woody shells that fit snugly together.Sclerenchyma consists of elongated dead cells with hard shells.
Main
As is clear from their name, they are the basis of all plant organs.They are assimilation and spare.The first is in the green part of the leaves and stem.These cells are the chloroplasts, which are responsible for photosynthesis.The storage tissues accumulate organic matter in most cases this starch.
