What are the differences in the structure of epithelial tissues? How does the structure of connective tissue differ from epithelial tissue? Basics of histology. Classification of fabrics. Epithelial tissue. Connective tissue. Functions of connective tissue

Epithelial tissue, or epithelium, covers the outside of the body, lines the cavities of the body and internal organs, and forms most of the glands.

Varieties of epithelium have significant variations in structure, which depends on the origin (epithelial tissue develops from all three germ layers) of the epithelium and its functions.

However, all species have common features that characterize epithelial tissue:

1. The epithelium is a layer of cells, due to which it can protect underlying tissues from external influences and carry out exchanges between the external and internal environments; Violation of the integrity of the formation leads to a weakening of its protective properties, leading to the possibility of infection.
2. It is located on the connective tissue (basal membrane), from which nutrients are supplied to it.
3. Epithelial cells have polarity, i.e. parts of the cell (basal) lying closer to the basement membrane have one structure, and the opposite part of the cell (apical) has another; Each part houses different components of the cell.
4. Has a high ability to regenerate (recovery). Epithelial tissue does not contain intercellular substance or contains very little of it.

Epithelial tissue formation

Epithelial tissue is made up of epithelial cells that are tightly connected to each other and form a continuous layer.

Epithelial cells are always located on the basement membrane. It delimits them from the loose connective tissue that lies below, performing a barrier function, and prevents the germination of the epithelium.

The basement membrane plays an important role in the trophism of epithelial tissue. Since the epithelium is vascularless, it receives nutrition through the basement membrane from the connective tissue vessels.

Classification by origin

Depending on their origin, epithelium is divided into six types, each of which occupies a specific place in the body.

1. Cutaneous - develops from the ectoderm, localized in the oral cavity, esophagus, cornea, and so on.
2. Intestinal - develops from the endoderm, lines the stomach, small and large intestine
3. Coelomic - develops from the ventral mesoderm, forms serous membranes.
4. Ependymoglial - develops from the neural tube, lining the cavities of the brain.
5. Angiodermal - develops from mesenchyme (also called endothelium), lines blood and lymphatic vessels.
6. Renal - develops from the intermediate mesoderm, found in the renal tubules.

Features of the structure of epithelial tissue

According to the shape and function of the cells, the epithelium is divided into flat, cubic, cylindrical (prismatic), ciliated (ciliated), as well as single-layer, consisting of one layer of cells, and multilayer, consisting of several layers.

Single layer

Single layer flat the epithelium is formed by a thin layer of cells with uneven edges, the surface of which is covered with microvilli. There are mononuclear cells, as well as with two or three nuclei.

Single layer cubic consists of cells with the same height and width, characteristic of the excretory duct of the glands. Single-layer columnar epithelium is divided into three types:

1. Bordered - found in the intestines, gall bladder, has adsorbing abilities.
2. Ciliated - characteristic of the oviduct, in the cells of which at the apical pole there are movable cilia (promote the movement of the egg).
3. Glandular - localized in the stomach, produces mucous secretion.

Single layer multi-row The epithelium lines the airways and contains three types of cells: ciliated, intercalated, goblet and endocrine. Together they ensure the normal functioning of the respiratory system and protect against the entry of foreign particles (for example, the movement of cilia and mucous secretions help remove dust from the respiratory tract). Endocrine cells produce hormones for local regulation.

Multilayer

Multilayer flat non-keratinizing the epithelium is located in the cornea, anal rectum, etc. There are three layers:

• The basal layer is formed by cylinder-shaped cells, they divide mitotically, some of the cells belong to the stem;
• spinous layer - cells have processes that penetrate between the apical ends of the cells of the basal layer;
• layer of flat cells - located on the outside, constantly dying and peeling off.

Multilayer flat keratinizing epithelium covers the surface of the skin. There are five different layers:

1. Basal - formed by poorly differentiated stem cells, together with pigment cells - melanocytes.
2. The spinous layer together with the basal layer form the growth zone of the epidermis.
3. The granular layer is built of flat cells, in the cytoplasm of which the keratoglian protein is located.
4. The stratum pellucida received its name because of its characteristic appearance upon microscopic examination of histological preparations. It is a uniform shiny stripe, which stands out due to the presence of elaidin in flat cells.
5. The stratum corneum consists of horny scales filled with keratin. The scales that are closer to the surface are susceptible to the action of lysosomal enzymes and lose contact with the underlying cells, so they are constantly exfoliated.

Transitional epithelium located in the kidney tissue, urinary canal, and bladder. Has three layers:

• Basal - consists of cells with intense coloring;
• intermediate - with cells of various shapes;
• integumentary - has large cells with two or three nuclei.

It is common for transitional epithelium to change shape depending on the state of the organ wall; they can flatten or acquire a pear-shaped shape.

Special types of epithelium

Acetowhite - This is an abnormal epithelium that becomes intensely white when exposed to acetic acid. Its appearance during a colposcopic examination makes it possible to identify the pathological process in the early stages.

Buccal - collected from the inner surface of the cheek, it is used for genetic testing and establishing family relationships.

Functions of epithelial tissue

Located on the surface of the body and organs, the epithelium is a border tissue. This position determines its protective function: protecting the underlying tissues from harmful mechanical, chemical and other influences. In addition, metabolic processes occur through the epithelium - absorption or release of various substances.

The epithelium that is part of the glands has the ability to form special substances - secretions, and also secrete them into the blood and lymph or into the ducts of the glands. This epithelium is called secretory or glandular.

Differences between loose fibrous connective tissue and epithelial tissue

Epithelial and connective tissue perform various functions: protective and secretory in the epithelium, supporting and transport in the connective tissue.

The cells of epithelial tissue are tightly connected to each other, there is practically no intercellular fluid. Connective tissue contains a large amount of intercellular substance; the cells are not tightly connected to each other.

Epithelial tissue- the outer surface of human skin, as well as the lining surface of the mucous membranes of internal organs, the gastrointestinal tract, lungs, and most glands.

The epithelium is devoid of blood vessels, so nutrition occurs due to the adjacent connective tissues, which are nourished by the bloodstream.

Functions of epithelial tissue

Main function skin epithelial tissue is protective, that is, limiting the impact of external factors on internal organs. Epithelial tissue has a multilayer structure, so keratinized (dead) cells are quickly replaced by new ones. It is known that epithelial tissue has increased restorative properties, which is why human skin is quickly renewed.

There is also intestinal epithelial tissue with a single-layer structure, which has absorptive properties, due to which digestion occurs. In addition, the intestinal epithelium tends to secrete chemicals, in particular sulfuric acid.

Human epithelial tissue covers almost all organs from the cornea of ​​the eye to the respiratory and genitourinary systems. Some types of epithelial tissue are involved in protein and gas metabolism.

The structure of epithelial tissue

Single-layer epithelial cells are located on the basement membrane and form one layer with it. Stratified epithelial cells are formed from several layers and only the lowest layer is the basement membrane.

According to the shape of the structure, epithelial tissue can be: cubic, flat, cylindrical, ciliated, transitional, glandular, etc.

Glandular epithelial tissue has secretory functions, that is, the ability to secrete secretions. The glandular epithelium is located in the intestine, making up the sweat and salivary glands, endocrine glands, etc.

The role of epithelial tissue in the human body

The epithelium plays a barrier role, protecting internal tissues, and also promotes the absorption of nutrients. When eating hot food, part of the intestinal epithelium dies and is completely restored overnight.

Connective tissue

Connective tissue– building matter that unites and fills the entire organism.

Connective tissue is presented in nature in several states at once: liquid, gel-like, solid and fibrous.

In accordance with this, they distinguish between blood and lymph, fat and cartilage, bones, ligaments and tendons, as well as various intermediate body fluids. The peculiarity of connective tissue is that there is much more intercellular substance in it than there are cells themselves.

Types of connective tissue

— Cartilaginous, there are three types:
a) Hyaline cartilage;
b) Elastic;
c) Fibrous.

— Bone(consists of forming cells - osteoblast, and destroying cells - osteoclast);

— Fibrous, in turn happens:
a) Loose (creates a frame for organs);
b) Formed dense (forms tendons and ligaments);
c) Unformed dense (the perichondrium and periosteum are built from it).

— Trophic(blood and lymph);

— Specialized:
a) Reticular (from it the tonsils, bone marrow, lymph nodes, kidneys and liver are formed);
b) Fat (subcutaneous energy reservoir, heat regulator);
c) Pigment (iris, nipple halo, anus circumference);
d) Intermediate (synovial, cerebrospinal and other auxiliary fluids).

Functions of connective tissue

These structural features allow connective tissue to perform various functions:

1. Mechanical The (supporting) function is performed by bone and cartilage tissue, as well as fibrous connective tissue of tendons;
2. Protective the function is performed by adipose tissue;
3. Transport The function is performed by liquid connective tissues: blood and lymph.

Blood ensures the transport of oxygen and carbon dioxide, nutrients, and metabolic products. Thus, connective tissue connects parts of the body to each other.

The structure of connective tissue

Most of the connective tissue is an intercellular matrix of collagen and non-collagen proteins.

In addition to it - naturally, cells, as well as a number of fibrous structures. The most important cells Fibroblasts can be called fibroblasts, which produce intercellular fluid substances (elastin, collagen, etc.).

Also important in structure are basophils (immune function), macrophages (exterminators of pathogens) and melanocytes (responsible for pigmentation).

Cells and their derivatives are combined into tissues. Tissue is a historically developed system of cells and intercellular substance, united by origin, structure and functions. The structure and functions of tissues are studied by histology.

There are 4 types of tissues in the human body: epithelial, connective, muscle, and nervous.

Organs are formed from tissues, with one tissue being dominant.

The epithelium can be superficial and glandular. Accordingly, the glandular system produces various substances and is part of various glands (remember the endocrine system from question 30). There are many types of epithelium; multilayered non-keratinizing and keratinizing (see question 29 skin) epithelium should be distinguished. The first covers the mucous membrane of the oral cavity, esophagus, and cornea of ​​the eye. The transitional epithelium of the bladder and urinary tract, which changes its thickness when stretched, deserves special discussion. The epithelium of the intestinal tract plays a huge role in our body. This is the bordered columnar epithelium of the intestine. Thanks to it, parietal digestion is carried out under the action of enzymes fixed on the cell membrane.

Connective tissue is a very large group of tissues. These are bone, cartilage, connective tissue itself, blood, lymph, brown fat, pigment tissue.

Muscle tissue forms striated muscles, cardiac muscle and smooth muscle fibers. They contain myofibrils consisting of actin and myosin; due to the sliding of myofibrils from these proteins, muscle contraction occurs.

Nervous tissue is represented by glia and neurons. Glial cells perform supporting, trophic, protective, insulating and secretory functions. There are glia (ependomyocytes) or simply ependyma, which lines the ventricles of the brain and the spinal canal. The surface is equipped with microvilli. It participates in the formation of cerebrospinal fluid and performs supporting and delimiting functions.

Astrocytes are the main supporting elements of the central nervous system. They transport substances from the capillary bed to the neuron. Microglia are NS macrophages and have phagocytic activity.

Oligodendrocytes are located near neurons and their processes. They are also called Schwann cells. They form the sheath of the nerve fiber (axon). Interception of the Ranvier at 0.3-1.5 mm. The myelin sheath provides and improves the isolated conduction of nerve impulses along axons and is involved in axon metabolism. In the nodes of Ranvier, during the passage of a nerve impulse, biopotentials increase. Some of the non-myelin nerve fibers are surrounded by Schwann cells that do not contain myelin.

The structural and functional unit of the nervous system organs is a neuron with processes extending from it. The processes of a nerve cell are divided into an axon (axial process) and tree-like branching dendrites. Typically, several dendrites extend from the body of a neuron. Dendrites perceive excitation and conduct them to the cell body. The axon, which extends from the cell in the singular, is characterized by uniform thickness and regular contour. It can give off branches (collaterals), which transmit impulses from the body of its cell to other cells. The axon carries the nerve impulse away from the cell body. A synapse is a specialized connection between two neurons. It ensures the transfer of excitation. The most common synapse is chemical; transmission is carried out using a mediator - a chemical substance. Synapses can be axo-dendritic (between an axon and a dendrite of neurons), axo-axonal (between two axons of neurons), axosomatic (between an axon and the soma or body of neurons). There may also be axovascular synapses between the axons of the neurosecretory cells of the hypothalamus and the capillary wall, ensuring the flow of neurohormone into the blood. There are neuromuscular synapses between the axon of the motor neuron and the skeletal muscle fiber. There may be neuro-secretory synapses between the nerve and the exocrine or endocrine gland.

The human body has a complex structure. It consists of various structures characterized by different levels of biological organization of living matter: cells with intercellular substance, tissues and organs. All structures of the body are interconnected, while cells with intercellular substance form tissues, organs are built from tissues, organs are combined into organ systems.

In the body, tissues are closely interconnected morphologically and functionally. The morphological connection is due to the fact that different tissues are part of the same organs. Functional connection is manifested in the fact that the activities of different tissues that make up the organs are coordinated. This consistency is due to the regulatory influence of the nervous and endocrine systems on all organs and tissues.

There are general and specialized fabrics. General tissues include:

epithelial or border tissues, their functions are protective and external exchange;

connective tissues or tissues of the internal environment, their functions are internal exchange, protective and supporting.

Various tissues, connecting with each other, form organs. It usually consists of several types of tissue, with one of them performing the main function of the organ (for example, muscle tissue in skeletal muscle), and the others performing auxiliary functions (for example, connective tissue in muscle). The main tissue of an organ that ensures its function is called its parenchyma, and the connective tissue that covers it from the outside and penetrates it in different directions is called stroma. The stroma of the organ contains blood vessels and nerves that supply blood and innervate the organ.

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State budgetary educational institution
secondary vocational education in Moscow
"Medical School No. 8
Department of Health of the City of Moscow"
(GBOU SPO "MU No. 8 DZM")

Methodological development of a practical lesson

(for students)

Academic discipline: OP.02 “Human Anatomy and Physiology” Subject: "Epithelial and connective tissue"

Speciality: 02/34/01 Nursing Course: 2

Teacher: Lebedeva T.N.

2015

Practical lesson

Topic: “Epithelial and

connective tissue “

Lesson objectives:

1. Students should know:

Basics of the structure and function of various types of epithelial and connective tissue.

1. Students should be able to:

Distinguish on microslides and posters: varieties of single-layer, stratified epithelium, glands, fibrous connective tissue, connective tissue with special properties, skeletal connective tissue.

Chronocard of the lesson.

Busy plan:

Organizational part - 2 min.

1. Control of the initial level of knowledge (survey), demonstration of cells, types of epithelial and connective tissues, overview of their functions. Assignment for independent work and

self-control - 15 min.

1. Independent work and self-control - 55 min.

3. Final control - 15 min.

1. Summing up the lesson and homework - 3 min.

Method of implementation.

Practical lesson with fragments on your own - search work.

Lesson equipment.

Posters, micropreparations with various types of epithelial tissue, glands, connective tissue, microscopes, “Atlas of normal human anatomy” by V.Ya. Lipchenko and others, textbooks by E.A. Vorobyova and others “Anatomy and Physiology”, L.F. Gavrilova and others. “Anatomy”.

Technological map of the theoretical lesson

Progress of the lesson:

MOTIVATION OF THE ACTIVITY

The human body has a complex structure. It consists of various structures characterized by different levels of biological organization of living matter: cells with intercellular substance, tissues and organs. All structures of the body are interconnected, while cells with intercellular substance form tissues, organs are built from tissues, organs are combined into organ systems.

In the body, tissues are closely interconnected morphologically and functionally. The morphological connection is due to the fact that different tissues are part of the same organs. Functional connection is manifested in the fact that the activities of different tissues that make up the organs are coordinated. This consistency is due to the regulatory influence of the nervous and endocrine systems on all organs and tissues.

There are general and specialized fabrics. General tissues include:

epithelial or border tissues, their functions are protective and external exchange;

connective tissues or tissues of the internal environment, their functions are internal exchange, protective and supporting.

Various tissues, connecting with each other, form organs. It usually consists of several types of tissue, with one of them performing the main function of the organ (for example, muscle tissue in skeletal muscle), and the others performing auxiliary functions (for example, connective tissue in muscle). The main tissue of an organ that ensures its function is called its parenchyma, and the connective tissue that covers it from the outside and penetrates it in different directions is called stroma. The stroma of the organ contains blood vessels and nerves that supply blood and innervate the organ.

Questions to control the initial level

1. The cell and its basic properties.
2. Main parts of the cell.
3. Cell organelles and their functions.
4. Fabric, main types of fabrics.
5. Position and functions of epithelial tissue.
6. Distinctive features of epithelial tissue.
7. Types of epithelial tissue.
8. What is mesothelium?
9. Types of single-layer epithelium.
10. Exo- and endocrine glands.
11. Features of the structure of connective tissue.
12. Functions of connective tissue.
13. Types of connective tissue.
14. Types of fibrous connective tissue.
15. The main types of cells of loose connective tissue.
16. Types of connective tissue with special properties.
17. Types of skeletal connective tissue.
18. Structure and types of cartilage tissue.
19. Bone tissue and its varieties.

Task No. 2

1. Using the literature recommended in paragraph 1 of assignment No. 1, study the structure of connective tissue and its difference from epithelial tissue. In this case, pay attention to the following morphological features of connective tissue:

1. it has a wide variety of structure;
2. it is less rich in cells than epithelial tissue;
3. its cells are always separated by significant layers of intercellular substance, including the main amorphous substance and special fibers (collagen, elastic, reticular);
4. it, in contrast to epithelial tissue, is a tissue of the internal environment and almost nowhere comes into contact with the external environment, internal cavities and participates in the construction of many internal organs, combining different types of tissues with each other;
5. The physicochemical characteristics of the intercellular substance and its structure largely determine the functional significance of the types of connective tissue.

In Fig. familiarize yourself with the connective tissue classification scheme.

1. Consider microslides with loose, dense, unformed and formed fibrous connective tissue, reticular, fatty, cartilage and bone tissues. On a microslide with loose fibrous connective tissue, find (against the background of the main amorphous substance, collagen and elastic fibers) the main cells of this type of tissue and become familiar with their functions:

1. fibroblasts participate in the production of the main amorphous substance and collagen fibers; fibroblasts that have completed their development cycle are called fibrocytes;
2. poorly differentiated cells are capable of turning into other cells (adventitial cells, reticular cells, etc.);
3. macrophages are capable of phagocytosis;
4. tissue basophils (mast cells) produce heparin, which prevents blood clotting;
5. plasma cells provide humoral immunity (synthesize antibodies - gamma globulins);
6. lipocytes (adipocytes) - fat cells accumulate reserve

fat;

1. pigmentocytes (melanocytes) - pigment cells contain the pigment melanin.

Loose fibrous connective tissue is present in all organs, as it accompanies blood and lymphatic vessels and forms the stroma of many organs.

When examining micropreparations with varieties of dense fibrous connective tissue, pay attention to the fact that in unformed dense tissue, against the background of a small number of cells, collagen and elastic fibers are densely located, intertwined and go in different directions, but in formed tissue, they go only in one direction. The first type of dense fibrous connective tissue forms a mesh layer of skin, and the second - muscle tendons, ligaments, fascia, membranes, etc.

When studying reticular, adipose, gelatinous, pigment tissue, note that they are all characterized by a predominance of homogeneous cells, with which the very name of types of connective tissue with special properties is usually associated.

Next, consider the types of skeletal connective tissue: cartilage and bone. Cartilage tissue consists of cartilage cells (chondrocytes), located in groups of 2-3 cells, ground substance and fibers. Depending on the structural features of the intercellular substance, there are 3 types of cartilage: hyaline, elastic and fibrous. Geoline cartilage forms almost all articular cartilages, cartilages of the ribs, airways, and epiphyseal cartilages. Elastic cartilage forms the cartilage of the auricle, part of the auditory tube, external auditory canal, epiglottis, etc. Fibrous cartilage is part of the intervertebral discs, pubic symphysis, intra-articular discs and menisci, sternoclavicular and temporomandibular joints. Bone tissue consists of bone cells (osteocytes) embedded in a calcified intercellular substance containing ossein (collogene) fibers and inorganic salts. It forms all the bones of the skeleton, being at the same time a depot of minerals, mainly calcium and phosphorus. Depending on the location of the ossein fiber bundles, two types of bone tissue are distinguished: coarse-fiber and lamellar. In the first fabric, bundles of ossein fibers are located in different directions. This tissue is characteristic of embryos and young organisms. The second tissue consists of bone plates in which ossein fibers are arranged in parallel bundles within the plates or between them. It can be compact and spongy. Compact bone tissue consists mainly of the middle part of long tubular bones, and spongy bone tissue forms their ends, as well as short bones. Flat bones contain both types of bone tissue. To crucify the body and the end

Task No. 3

1. Fill the LDS of “epithelial tissue”
2. Fill the “connective tissue” LDS
3. Solve problems:

Problem 1

How can one explain the high strength of stratified squamous epithelium, which remains intact (undamaged) even after fairly strong mechanical stress?

Problem 2

two classmates Kolya and Misha, 11 years old, while sledding down a steep hill in winter, turned over and were injured: Kolya - an extensive superficial abrasion in the area of ​​the right knee joint and lower leg, and Misha - a deep contusion-laceration wound measuring 2 x 0.5 cm in the area of ​​the eminence of the thumb of the left hand. How do you think soft tissue regeneration and healing will occur in both students?

Problem 3

Name the main cells of loose fibrous connective tissue that are actively involved in protecting the body, and the specific functions of these cells.

Problem 4

What is the macrophage system of the body and what cells belong to it?

long tubular bone, visually familiarize yourself with the structure of these two types of bone tissue.

1. Draw in sketchbooks. 4-8 on pp. 22-24, 26 “Anatomy”

L.F. Gavrilova and others. Some types of connective tissue: loose, dense, unformed and formed, reticular, fatty, cartilaginous and bone. The work of sketching fabrics in albums can be completed at home.

Are common

functions

General
character -
ristics

Classy -
fication

Genetic and
morpho-functional
nal types
epithelium

Variety
ty epithelium

Morpho-funk -
national
characteristics
cells

Character
locate -
nuclei

Private

functions

Test on the topic:

“Epithelial tissue

1. indicate which of the following functions are common functions of epithelial tissues:

a) external exchange,

b) internal exchange,

c) protective function,

d) trophic function.

1. Indicate which of the following mechanisms constitute the external exchange function:

a) accumulation of substances in the body,

b) the entry of substances into the body,

c) synthesis of a substance,

d) release of substances from the body.

1. Indicate which of the following characteristics are inherent in epithelial tissues:

a) the presence of intercellular substance,

b) cell layer,

c) border canopy/canopy,

d) the presence of blood vessels,

e) absence of blood vessels,

e) the presence of a basement membrane,

g) absence of basement membrane,

h) polar differentiation,

i) cell apolarity,

j) low regenerative capacity,

k) high regenerative capacity.

1. Indicate which of the following epithelia belong to the group of single-layer epithelia:

a) flat,

b) cubic,

c) cylindrical,

d) transitional,

d) keratinizing.

1. Indicate which of the following functions are inherent in multilayered epithelia:

a) motor,

b) secretory,

c) protective.

1. Indicate which of the listed methods of secretion are characterized by exocrine (1), endocrine (2), and mixed (3) glands:

a) release of secretions into the internal environment of the body,

b) release of secretion into the external environment.

1. Name the general functions of epithelial tissues.
2. Name the types of single-layer epithelium based on their shape.
3. Name the types of stratified epithelium.
4. What tissue always underlies epithelial tissue?
5. List the organelles of special importance found in epithelial tissue.

Test on the topic:

" Connective tissue "

Reticular tissue

1. Indicate which of the following organs includes reticular tissue:

a) muscles

b) tendons,

c) skin,

d) hematopoietic organs.

1. Indicate which of the following components are part of the intercellular substance of reticular tissue:

a) the main substance,

b) basement membrane,

c) lymph,

d) collagen fibers,

e) reticular fibers.

1. Indicate which of the following functions is performed by the intercellular substance of reticular tissue:

a) supporting,

b) protective,

c) contractile.

1. Indicate which of the following functions is performed by reticular tissue:

a) supporting,

b) contractile,

c) trophic,

d) secretory,

d) protective.

Loose fibrous unformed connective tissue.

1. Indicate which of the following components are part of loose fibrous unformed connective tissue:

a) basement membrane,

b) cellular elements,

c) mesocellular substance.

1. Indicate which of the following functions is performed by loose fibrous unformed connective tissue:

a) trophic,

b) participation in external exchange,

c) supporting,

d) excretory,

d) protective.

1. Indicate which of the following types of fibers are part of loose fibrous unformed connective tissue:

a) chondriline,

b) reticular,

c) osseine,

d) elastic,

d) collagen.

1. Indicate which of the listed patterns of fiber arrangement are characteristic of loose fibrous unstructured connective tissue:

a) orderly,

b) disordered.

1. Indicate which of the following cellular elements are part of loose fibrous unformed connective tissue:

a) fibroblasts,

b) fibrocytes,

c) leukocytes,

d) chondroblasts,

d) neurocytes,

e) histiocytes-macrophages,

g) epithelial cells,

h) plasmatic,

i) obese,

j) reticular,

k) eh!syruvye,

m) pigment,

m) poorly differentiated.

1. Indicate which of the following functions the fibroblast performs:

a) phagocytosis,

b) production of antibodies,

c) formation of the main substance,

d) formation of fibers.

1. Indicate which of the following functions is performed by the histiocyte-macrophage:

a) supporting,

b) the formation of the main substance of loose fibrous unformed connective tissue,

c) protective.

1. Indicate which of the following functions is performed by a plasma cell:

a) the formation of the main substance of loose fibrous unformed connective tissue,

b) supporting,

c) production of antibodies,

d) production of proteolytic enzymes.

Dense connective tissues.

1. Indicate which of the following tissues are included in the group of dense connective tissues:

a) coarse fiber,

b) lamellar,

c) unformed,

d) decorated.

1. Indicate the location in the body of dense, unformed (1) and dense, formed (2) connective tissue:

a) tendons,

b) mesh layer coe/si,

c) ligaments.

1. Indicate which of the following components are part of the intercellular substance of dense connective tissues:

a) bundles of reticular fibers,

b) lymph, c) bundles of collagen fibers,

d) basic substance.

1. Indicate which of the following functions is performed by dense connective tissues:

a) trophic,

b) supporting,

c) protective.

Cartilage tissue

1. Indicate which of the following components are part of cartilage tissue:

a) periosteum,

b) perichondrium,

c) cellular elements,

d) terminal glandular sections,

e) basic substance,

e) chondrin fibers,

g) ossein fibers.

1. Indicate which of the following functions is performed by cartilage tissue:

a) regenerative,

b) supporting,

c) trophic,

d) participation in carbohydrate metabolism,

d) protective.

1. Indicate which of the following cells are part of cartilage tissue:

a) fibroblast,

b) chondroblast,

c) fibrocyte,

d) chondrocyte.

1. Please specify. In which of the following structures is elastic cartilage localized?

a) ribs

b) airways,

c) auricle,

d) epiglottis,

e) skeleton of the embryo,

e) cartilages of the larynx.

1. Indicate which of the following characteristics are inherent in the intercellular substance of elatic cartilage:

a) a lot of elastic fibers,

b) rich in water,

c) few collagen fibers,

d) the presence of areas of calcification,

e) absence of areas of calcification.

1. Indicate in which of the following structures collagen-fibrous cartilage is localized:

a) meeucall it full-time disks,

b) auricle,

c) symphysis of the pubic bones,

d) ribs

d) airways,

e) sternoclavicular joint,

g) submaxillary fuss,

h) cartilages of the larynx,

i) places of transition of fibrous tissue into hyaline cartilage.

Bone

1. Indicate which of the following functions are characteristic of bone tissue:

a) participation in carbohydrate metabolism,

b) supporting,

c) secretory,

d) participation in mineral metabolism.

1. Indicate which of the following cells are part of bone tissue:

a) fibroblast,

b) osteoblast,

c) mast cell,

d) osteocyte,

e) osteoclast,

e) chondrocyte,

e/c) plasma cell.

1. Indicate which of the following components are included in the intercellular substance of cartilage (1) and bone (2) tissues:

a) ossein fibers,

b) chondrin fibers,

c) osseomucoid,

d) inorganic salts,

e) chondromucoid,

e) glycogen.

1. Indicate what types of bone plates are contained in lamellar bone tissue:

a) osteon plates,

b) closing,

c) delimiting,

d) insertion,

e) internal general,

e) basal,

e/s) external general.

1. Indicate the nature of the arrangement of ossein fibers in coarse-fiber (1) and lamellar (2) bone tissue:

a) in an orderly manner,

b) randomly.

1. Indicate which of the following structures helps bone grow in length (1) and width (2):

a) epiphyseal growth plate,

b) periosteum.

Sample answers to the test:
“Epithelial tissue”

1. a, c
2. b, d
3. b, c, d, f, h, l
4. a B C
5. 1-6, 2-a, 3 - a, b
6. a-external exchange, b-protective (barrier)
7. a-flat, b-cubic, c-cylindrical
8. a-keratinizing, b-non-keratinizing, c-transitional
9. a-connective tissue
10. a-tonofibrils, b-cilia, c-microvilli

Sample answers to the test:
“ Connective tissue ”

Reticular tissue

1. macrophages - capable of phagocytosis.
2. Plasmocytes (plasma cells) synthesize antibodies - gamma globulins and provide humoral immunity.
3. tissue basophils - produce heparin, which prevents blood clotting.

Question 1. What tissue does the skin, walls of the oral cavity, ear and nasal cartilage consist of?

The skin and walls of the oral cavity consist of epithelial tissue, and the ear and nasal cartilages consist of connective tissue.

Questions after the paragraph

Question 1. What is called fabric?

Groups of cells and intercellular substance that have a similar structure and origin and perform common functions are called tissues.

Question 2. What fabrics do you know? Make and fill out the “Variety of Fabrics” diagram.

In the body of animals and humans, there are four main groups of tissues: epithelial, connective, muscle and nervous. In muscles, for example, muscle tissue predominates, but along with it there is also connective and nervous tissue. Tissue can consist of both identical and different cells.

Question 3. How do connective tissues differ from epithelial tissues?

Connective tissue contains cells that can fight microorganisms, and if the main tissue of an organ is damaged, this tissue is able to replace the lost elements. Thus, scars formed after injuries consist of connective tissue. True, it cannot perform the functions of the tissue that connective tissue replaced.

Question 4. What types of epithelial and connective tissue do you know?

Types of epithelial tissue: squamous epithelium, cuboidal epithelium, ciliated epithelium, columnar epithelium.

Connective tissues include supporting tissues - cartilage and bone; liquid tissues - blood and lymph, loose fibrous tissue that fills the space between organs, accompanying blood vessels and nerves; adipose tissue; dense fibrous tissue that makes up tendons and ligaments.

Question 5. What properties do muscle tissue cells have - smooth, skeletal, cardiac?

The general properties of all muscle tissues are excitability and contractility. In response to irritation, muscle tissue contracts. Thanks to contraction, all human movements and the work of his internal organs are carried out.

Question 6. What functions do neuroglial cells perform?

Neuroglial cells perform servicing functions in relation to them: protective and supportive, nutritional and electrically insulating.

Question 7. What is the structure and properties of neurons?

A neuron consists of a body and processes. The body of the neuron contains the nucleus and the main cellular organelles. Neuron processes vary in structure, shape and function.

Question 8. Compare dendrites and axons. What are their similarities and what are their fundamental differences?

Dendrite is a process that transmits excitation to the neuron body. Most often, a neuron has several short branched dendrites. However, there are neurons that have only one long dendrite.

An axon is a long process that transmits information from the neuron body to the next neuron or to the working organ. Each neuron has only one axon. The axon branches only at the end, forming short branches - terminal and.

Question 9. What is a synapse? Tell us about the principles of its work.

Places of contact between individual neurons or between neurons and the cells they control are called synapses.

At the extended end of the axon, special vesicles - vesicles - contain a biologically active substance from the group of neurotransmitters. When a nerve impulse propagating along an axon reaches its end, the vesicles approach the membrane, integrate into it, and transmitter molecules are released into the synaptic cleft. These chemicals act on the membrane of another cell and in this way transmit information to the next neuron or cell of the controlled organ. The neurotransmitter can activate the next cell, causing it to become excited. However, there are mediators that lead to inhibition of the next neuron. This process is called inhibition.

Excitation and inhibition are the most important processes occurring in the nervous system. It is thanks to the balance of these two opposing processes that at each moment in time nerve impulses can arise only in a strictly defined group of nerve cells. Our attention, the ability to concentrate on a specific activity, is possible thanks to neurons that cut off redundant information. Without them, our nervous system would very quickly become overloaded and would not be able to function normally.

Tasks

1. Look for scars on your skin or those you know. Determine what fabric they are made of. Explain why they do not tan and differ in structure from healthy areas of skin.

Scars are made of connective tissue. These cells lack the pigment melanin, so these areas of the skin do not tan in the sun.

2. Look at samples of epithelial and connective tissue under a microscope. Using Figures 16 and 17, tell us about their structure.

The epithelial cell has a thick membrane (a small amount of intercellular substance). Connective tissue has a high ability to regenerate (the main function is performed by the intercellular substance.

3. In Figure 20, find the neuron body, nucleus, dendrites and axon. Determine in which direction the nerve impulses will go along the processes if the cell is excited.

If the cell is excited, the nerve impulse always moves from the cell body along the axon to the synapses.

4. It is known that the thoracic and abdominal cavities are separated by the diaphragm, which is involved in breathing. Does it consist of smooth or striated muscles? Hold your breath, inhale and exhale voluntarily and answer this question.

The diaphragm is formed by muscle tissue. It consists of smooth muscles.

5. There are many classifications of neurons. Some of them you already know. Using additional sources of information, suggest other classifications than those presented in the textbook.

Classification of neurons by the number of processes:

1. Multipolar neurons - neurons with numerous processes

2. Bipolar neurons - have 2 processes

3. Unipolar

a) Pseudounipolar (have 1 process, although initially they are formed as two-processes, but the bases of the processes are very close and it seems as if there is 1 process)

b) True unipolar - 1 process