The tissues are the organisms of all animals and plants on the planet. They are different, and each type of fabric performs its functions.
What are the fabrics made of?
The smallest structural part of the body is the cell. All types of tissues, both plant and animal, are composed of them.
Cell structure
This structure can exist as a separate organism. Creatures such as bacteria and protozoan eukaryotes are represented by one cell. This component of a living organism consists of such parts: a plasma membrane, a cytoplasm represented by a colloidal solution, a nucleus and organelles - permanent structures, each of which performs certain functions. The structure of the animal cell contains such organelles: the cell center, ribosomes, lysosomes, mitochondria, the Golgi complex and the endoplasmic reticulum. Plant cells differ from them in that they contain vacuoles (at first several, and as cells age, they merge into one central one), as well as plastids: chromoplasts, leukoplasts and chloroplasts.
The plasma membrane of an animal cell consists of three layers: two protein and a lipid between them. This shell, in turn, is surrounded by glycocalyx, which includes polysaccharides, glycolipids, glycoproteins. Organelles perform such functions: the cell center - distribution of chromosomes during division, ribosomes - protein synthesis, lysosomes - the breakdown of substances using enzymes, mitochondria - energy production, the Golgi complex - the accumulation and transformation of certain substances, the endoplasmic reticulum (reticulum) - transport of chemical compounds. The amount of some organelles in a cell depends on what type of tissue it is part of.
Animal tissue structure
The tissue of animals consists of cells united by an intercellular substance. Depending on the purpose of the fabric, it can have a different composition, be contained in more or less. Tissues in animals are of the following types:
- connecting;
- epithelial;
- Nervous
- muscle
Connective tissue
They are of such types: dense and loose fibrous, cartilage, bone, blood and lymph, adipose, reticular tissue. All of them are united by the presence of a large amount of intercellular substance. Dense fibrous tissue consists mainly of fibers, loose fibrous tissue - of amorphous mass. Bone has a large amount of solid intercellular substance, consisting of inorganic chemical compounds. The intercellular substance of cartilage is composed of organic substances. Reticular tissue contains stem cells from which blood cells form. The composition of blood and lymph includes a large amount of fluid. The structure of animal tissue of this type consists of specific cells, they are also called blood cells. Their types:
- red blood cells;
- white blood cells;
- platelets.
Each of them performs its functions. Red blood cells are presented in the form of round structures containing hemoglobin. They are responsible for the transport of oxygen throughout the body. White blood cells perform an immune function. Platelets are responsible for blood coagulation in case of damage to the skin.
Animal epithelial tissue
The epithelium is divided into several types:
- flat;
- cubic;
- cylindrical;
- ciliated;
- sensory;
- glandular.
The squamous epithelium is represented by flattened cells that are in the form of polygons. This tissue is located in the esophagus and mouth. Cubic epithelial tissue of the animals lining the tubules of the kidneys, cylindrical - the stomach and intestines, ciliary - the respiratory tract, sensory - the nasal cavity. Glandular is a component of the glands. The cells of this particular tissue produce hormones, milk, etc.
Muscle tissue
They are also divided into several types:
Muscular animal tissue of the first type is a component of the muscles of the musculoskeletal system. Muscles of internal organs, for example, the intestines, stomach, uterus, etc. are formed from the smooth one. The cardiac is distinguished by the fact that its fibers are intertwined - this allows them to contract faster.
Animal nervous tissue
This type of tissue consists of spindle-shaped, stellate or spherical cells - neurons, and intercellular substance - mesogley, which provides neurons with nutrients. Neurons are composed of the body, axon, and dendrites, the processes by which cells connect. They are needed to carry the signal.