Comparative table of epithelial and connective tissue. difference between epithelial tissue and connective tissue

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 related morphologically and functionally. The morphological connection is due to the fact that different tissues are part of the same organs. The functional connection is manifested in the fact that the activity of different tissues that make up the organs is coordinated. This consistency is due to the regulatory influence of the nervous and endocrine systems to all organs and tissues.

Distinguish fabrics general meaning and specialized. Common tissues include:

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

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

Different tissues join together to form organs. It usually consists of several types of tissues, and one of them performs the main function of the organ (for example, muscle tissue in the skeletal muscle), while others perform auxiliary functions (for example, connective tissue in the muscle). The main tissue of an organ that provides its function is called its parenchyma, and the connective tissue covering it from the outside and penetrating it in different directions is called stroma. In the stroma of the organ, vessels and nerves pass, carrying out blood supply and innervation of the organ.

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State budget 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")

Methodical development practical session

(for students)

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

Speciality: 34.02.01 Nursing Course: 2

Lecturer: Lebedeva T.N.

2015

Practical lesson

Topic: “Epithelial and

connective tissue “

Lesson objectives:

1. Learners should know:

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

1. Learners should be able to:

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

Lesson timeline.

Busy plan:

Organizational part - 2 min.

1. Control of the initial level of knowledge (survey), demonstration of cells, varieties of epithelial and connective tissues, review 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.

Conduct method.

Practical exercise with fragments independently - 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. etc. "Anatomy".

Routing theoretical lesson

SECTION 2. Selected issues of cytology and histology
Topic 2.2. Fundamentals of histology. Classification of tissues. Epithelial, connective tissue.
class number	3. Epithelial, connective tissue.
Lesson type	occupation of the assimilation of new knowledge, generalization and systematization of knowledge
Form holding	lecture
Lesson objectives Know:	definition of the concept of "Tissue" tissue classification localization, structural features, varieties and functions of epithelial tissues (integumentary and glandular epithelium and their varieties) connective tissue classification localization, structural features, varieties and functions of connective tissues (fibrous, with special properties, skeletal tissues, their varieties)
Equipment for the lesson	board, chalk ■ tables " Stratified epithelium”, “Single-layer epithelium”, “Glandular epithelium”, “Scheme of the structure of the glands” of the table “Lamellar bone tissue. The structure of the tubular bone", "Cartilaginous tissue", "Dense fibrous connective tissue", "Loose fibrous connective tissue", "Adipose tissue"
Educational literature	Shvyrev A.A. Human anatomy and physiology with the basics of general pathology. Textbook for medical schools and colleges. Rostov-on-Don. "Phoenix", 2014, - 412 p. Samusev R.P., Lipchenko V.Ya. Atlas of human anatomy [Text]. M.: LLC "Izd. House "Onyx 21st century": LLC "World and Education", 2007.

Lesson progress:

	stage classes	time (min.)	methods	teacher activity	student activity
	Organization onion moment			Fills out a journal, tells students the topic, goals and plan of the lesson.	Write down the topic and objectives of the lesson in a notebook.
	Motivation educational activities		explanatory illustrative	Motivates students to learn new material	Listen and answer teacher's questions
	Statement new material		explanatory illustrative reproductive partially search.	Explains new material, accompanies the explanation with a demonstration of tables, tablets, anatomical models and models, as well as images of drawings and diagrams on the board.	Write new material in a notebook, draw diagrams; consider visual aids; analyze the situations proposed by the teacher as an example.
	Reflection		Problem.	Focuses students' attention on the most important moments of the lesson. Answers the questions. Offers to summarize the studied material, to assess the degree of achievement of the objectives of the lesson.	Ask questions and summarize what has been learned in class. Evaluate the individual degree of achievement of goals.
	Results classes			Evaluates the work of the group in class, gives homework.	Write down homework.
Total class time 90 min

MOTIVATION OF THE LESSON

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 related morphologically and functionally. The morphological connection is due to the fact that different tissues are part of the same organs. The functional connection is manifested in the fact that the activity of different tissues that make up the organs is coordinated. This consistency is due to the regulatory influence of the nervous and endocrine systems on all organs and tissues.

Distinguish fabrics of general value and specialized. Common tissues include:

epithelial or border tissues, their functions - 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 tissues, and one of them performs the main function of the organ (for example, muscle tissue in the skeletal muscle), while others perform auxiliary functions (for example, connective tissue in the muscle). The main tissue of an organ that provides its function is called its parenchyma, and the connective tissue covering it from the outside and penetrating it in different directions is called stroma. In the stroma of the organ, vessels and nerves pass, carrying out blood supply and innervation of the organ.

Baseline Control Questions

1. Cell and its main properties.
2. The main parts of the cell.
3. Cell organelles and their functions.
4. Fabric, basic types of fabrics.
5. Position and function of epithelial tissue.
6. Distinctive features of epithelial tissue.
7. Types of epithelial tissue.
8. What is mesothelium?
9. Varieties of single-layer epithelium.
10. Exo- and endocrine glands.
11. Structural features of connective tissue.
12. Connective tissue functions.
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 cartilage tissue.
19. Bone tissue and its varieties.

Task number 2

1. Using the literature recommended in paragraph 1 of task No. 1, study the structure of connective tissue and its difference from epithelial tissue. At the same time, pay attention to the following morphological features of the connective tissue:

1. it has a great variety in 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 never comes into contact with the external environment, internal cavities and participates in the construction of many internal organs, uniting different kinds tissues among themselves;
5. the physicochemical features of the intercellular substance and its structure largely determine the functional significance of the types of connective tissue.

On fig. Familiarize yourself with the connective tissue classification scheme.

1. Consider micropreparations with loose, dense irregular and formed fibrous connective tissue, reticular, adipose, cartilage and bone tissues. On a micropreparation 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 familiarize yourself with their functions:

1. fibroblasts are involved in the production of the main amorphous substance and collagen fibers; fibroblasts that have completed the development cycle are called fibrocytes;
2. poorly differentiated cells are able to transform 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 the blood and lymphatic vessels and forms the stroma of many organs.

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

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

Next, consider the varieties 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, select 3 types of cartilage: hyaline, elastic and fibrous. Geolin cartilage forms almost all articular cartilage, cartilages of the ribs, airways, 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, intraarticular discs and menisci, sternoclavicular and temporomandibular joints. Bone tissue consists of bone cells (osteocytes) immured in a calcified intercellular substance containing ossein (collagen) 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 bundles of ossein fibers, two types of bone tissue are distinguished: coarse-fibered and lamellar. In the first tissue, bundles of ossein fibers are located in different directions. This tissue is inherent in 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 mainly consists of the middle part of long tubular bones, and spongy bone tissue forms their ends, as well as short bones. In flat bones, there is both one and the other bone tissue. On the sing of the body and the end

Task number 3

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

Task 1

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

Task 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 right knee joint and shins, and Misha - a deep bruised-lacerated wound measuring 2 x 0.5 cm in the area of ​​​​the eminence thumb left hand. How, in your opinion, will regeneration and healing of soft tissues occur in both schoolchildren?

Task 3

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

Task 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 the albums from fig. 4-8 on pages 22-24, 26 of Anatomy

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

Are common

functions

General
character -
ristika

Classy -
fiction

Genetic and
morpho-function
physical types
epithelium

Varied
ty epithelium

Morpho funk -
rational
characteristic
cells

Character
located -
nuclei

Private

functions

Related quiz:

“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. Specify which of the following mechanisms constitute the external exchange function:

a) the accumulation of substances in the body,

b) the intake of substances into the body,

c) the synthesis of a substance,

d) excretion of substances from the body.

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

a) the presence of intercellular substance,

b) cell layer,

c) borderline poloe / canopy,

d) the presence of blood vessels,

e) lack of blood vessels,

e) the presence of a basement membrane,

g) the absence of a basement membrane,

h) polar differentiation,

i) cell apolarity,

j) low regenerative capacity,

k) high regenerative capacity.

1. Specify which of the following epithelium belong to the group of single-layered epithelium:

a) flat

b) cubic,

c) cylindrical,

d) transitional

e) keratinizing.

1. Specify which of the following functions are inherent in stratified epithelium:

a) motor

b) secretory,

c) protective.

1. Specify which of the following secretion secretion methods characterize exocrine (1), endocrine (2), and mixed (3) glands:

a) secretion into the internal environment of the body,

b) release of the secret into the external environment.

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

Related quiz:

" Connective tissue "

Reticular tissue

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

a) muscles

b) tendons

c) skin

d) hematopoietic organs.

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

a) base material

b) basement membrane,

c) lymph

d) collagen fibers

e) reticular fibers.

1. Specify which of the following functions are performed by the intercellular substance of the reticular tissue:

a) base

b) protective,

c) contractile.

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

a) base

b) contractile,

c) trophic,

d) secretory,

e) protective.

Loose fibrous irregular connective tissue.

1. Specify which of the following components are part of loose fibrous irregular connective tissue:

a) basement membrane

b) cellular elements,

c) meucellular substance.

1. Specify which of the following functions are performed by loose fibrous unformed connective tissue:

a) trophic

b) participation in external exchange,

c) support

d) excretory,

e) protective.

1. Specify which of the following types of fibers are part of loose fibrous irregular connective tissue:

a) chondrins

b) reticular,

c) ossein,

d) elastic,

e) collagen.

1. Specify which of the following patterns of fiber arrangement are characteristic of loose fibrous unformed connective tissue:

a) ordered

b) disordered.

1. Specify which of the following cellular elements are part of loose fibrous irregular connective tissue:

a) fibroblasts,

b) fibrocytes,

c) leukocytes,

d) chondroblasts,

e) neurocytes,

e) macrophage histiocytes,

g) epitheliocytes,

h) plasma,

i) obese

j) reticular,

l) e!

m) pigment,

m) undifferentiated.

1. Specify which of the following functions are performed by fibroblast:

a) phagocytosis

b) production of antibodies,

c) the formation of the main substance,

d) the formation of fibers.

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

a) base

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

c) protective.

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

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

b) support,

c) the production of antibodies,

d) production of proteolytic enzymes.

Dense connective tissues.

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

a) coarse fiber

b) lamellar,

c) unformed

d) decorated.

1. Specify the localization of dense unformed (1) and dense formed (2) connective tissues in the body:

a) tendons

b) mesh layer coe / si,

c) links.

1. Specify 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) base material.

1. Specify which of the following functions are performed by dense connective tissues:

a) trophic

b) support,

c) protective.

cartilage tissue

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

a) periosteum

b) perichondrium,

c) cellular elements,

d) terminal glandular sections,

e) the main substance,

e) chondrin fibers,

g) ossein fibers.

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

a) regenerative,

b) support,

c) trophic,

d) participation in carbohydrate metabolism,

e) protective.

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

a) fibroblast

b) chondroblast,

c) fibrocyte,

d) chondrocyte.

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

a) ribs

b) airways

V) Auricle,

d) epiglottis,

e) the skeleton of the embryo,

e) cartilage of the larynx.

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

a) a lot of elastic fibers,

b) rich in water

c) few collagen fibers,

d) the presence of calcification sites,

e) the absence of calcification sites.

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

a) meeupozv he face-to-face disks,

b) auricle,

c) symphysis of the pubic bones,

d) ribs

d) airways

e) sternoclavicular joint,

g) non-mandibular fussiness,

h) cartilage of the larynx,

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

Bone

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

a) participation in carbohydrate metabolism,

b) support,

c) secretory,

d) participation in mineral metabolism.

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

a) fibroblast

b) osteoblast,

c) mast cell

d) osteocyte,

e) osteoclast,

e) chondrocyte,

e/s) plasma cell.

1. Specify which of the following components are part of 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. Specify what types of bone plates are contained in lamellar bone tissue:

a) osteon plates,

b) closing,

c) delimiter

d) insert,

e) internal general,

e) basal,

e / s) external general.

1. Specify the nature of the location of ossein fibers in coarse fibrous (1) and lamellar (2) bone tissue:

a) orderly

b) disorderly.

1. Specify which of the following structures is used for bone growth in length (1) and width (2):

a) epiphyseal growth plate

b) periosteum.

Sample answers to the test:
"Epithelial tissue"

1. a, in
2. b, d
3. b, c, e, 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. Plasma cells (plasma cells) synthesize antibodies - gamma globulins and provide humoral immunity.
3. tissue basophils - produce heparin, which prevents blood clotting.

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

Varieties of the epithelium have significant variations in the 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, which characterize the epithelial tissue:

1. The epithelium is a layer of cells, due to which it can protect the underlying tissues from external influences and exchange between the external and internal environment; violation of the integrity of the formation leads to a weakening of its protective properties, to the possibility of infection.
2. It is located on the connective tissue (basement membrane), from which nutrients come 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 contains different components of the cell.
4. It has a high ability to regenerate (recovery). Epithelial tissue does not contain intercellular substance or contains very little of it.

Formation of epithelial tissue

Epithelial tissue is built from epithelial cells, which are tightly connected to each other and form a continuous layer.

Epithelial cells are always found on the basement membrane. It delimits them from the loose connective tissue, which 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 devoid of blood vessels, it receives nutrition through the basement membrane from the vessels of the connective tissue.

Origin Classification

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

Features of the structure of epithelial tissue

According to the shape and function of 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.

Table of functions and properties of epithelial tissue
Type of epithelium	Subtype	Location	Functions
Single layer epithelium	Flat	Blood vessels	BAS secretion, pinocytosis
	Cubic	Bronchioles	Secretory, transport
	Cylindrical	Gastrointestinal tract	Protective, adsorption of substances
Single layer multi-row	Columnar	vas deferens, duct of the epididymis	Protective
	Pseudo stratified ciliated	Respiratory tract	Secretory, transport
multilayer	transitional	Ureter, urinary bladder	Protective
	Flat nonkeratinized	Oral cavity, esophagus	Protective
	Flat keratinizing	Skin	Protective
	Cylindrical	Conjunctiva	Secretory
	Cubic	sweat glands	Protective

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 single-nucleated cells, as well as with two or three nuclei.

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

1. Bordered - found in the intestines, gallbladder, has adsorbent properties.
2. Ciliated - characteristic of the oviducts, in the cells of which there are mobile cilia at the apical pole (contribute to the movement of the egg).
3. Glandular - localized in the stomach, produces a mucous secret.

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

multilayer

Stratified squamous nonkeratinized the epithelium is located in the cornea, anal rectum, etc. There are three layers:

• The basal layer is formed by cells in the form of a cylinder, they divide in a mitotic way, 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;
• a layer of flat cells - are outside, constantly die off and exfoliate.

Stratified epithelium

Stratified squamous keratinizing epithelium covers the surface of the skin. There are five different layers:

1. Basal - formed by poorly differentiated stem cells, together with pigmented - 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 is the protein keratoglian.
4. The shiny layer got its name because of its characteristic appearance during microscopic examination of histological preparations. It is a homogeneous shiny band, which stands out due to the presence of elaidin in the flat cells.
5. The stratum corneum consists of horny scales filled with keratin. 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 peeled off.

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

• Basal - consists of cells with intense color;
• 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 reveals pathological process in the early stages.

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

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: protection of the underlying tissues from harmful mechanical, chemical and other influences. In addition, metabolic processes occur through the epithelium - the absorption or release of various substances.

The epithelium, which is part of the glands, has the ability to form special substances - secrets, as well as release them into the blood and lymph or into the ducts of the glands. Such an epithelium is called secretory, or glandular.

Differences between loose fibrous connective tissue and epithelial

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

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

Biology lesson in grade 8 Lesson number 6

Lesson topic: Basic human tissues. epithelial and connective tissues.

The purpose of the lesson: give a general idea of ​​the diversity of tissues in the human body and their functions;

Lesson objectives:

Educational: to reveal the concept of the tissues of a multicellular animal organism and the classification of tissues.

At the level of the periodontal ligament, there may be some structural changes due to various trauma or forces that may be applied in the occlusal areas. One such change may be a torn ligament that accompanies hemorrhage, necrosis, vascular destruction or resorption, and bone resorption. Thus, in this situation, the tooth loses significantly from the attachment holding it in the alveoli and becomes weak. The repair process can happen quickly due to the specific properties of collagen.

Vascularization of the periodontal ligament

The cells that adhere to the periodontal ligament are: fibroblasts, osteoblasts, osteoclasts, cementoblasts, Malassi cell debris, macrophages, cells associated with vascular and neural structures. Clarification of the blood Provided by the upper and lower alveolar arteries, which flow into the alveolar bone, taking the form of interalveolar arteries.

Developing: develop the ability to compare the structural features of tissues in connection with the functions performed.

Educational: to cultivate the spirit of competition, the speed of thinking, the ability to analyze, to carry out aesthetic education.

Equipment: drawings "Human cell",

Teaching method: verbal, explanatory and illustrative.

Innervation of the periodontal ligament

Functions performed by the periodontal ligament

Structure of alveolar processes. The actual alveolar bone, also called hard lamellae or macadam, is the bony part of the attachment of the ligament fibers and coincides with the facial bone. The alveolar supporting bone includes both the spongy and the cortical plate and is the outer body and limit of the alveolar process.

As we age, tooth loss leads to narrow jaws, which leads to shortening of the processes, which ultimately leads to bone loss. The alveolar processes are extremely sensitive to the transmission of sensations of pressure and tension, which by their very nature stimulate the process of bone formation.

Predicted result: Students will study the tissues of the human body.

Lesson type: revealing the content of the topic.

Type of lesson: combined.

Lesson plan:

1. Class organization.

2. Checking homework.

4. Homework.

5. Viewing a video clip

During the classes:

Bone fasciitis. Occurs in the dental follicle and is the point of attachment of fiber bundles in the periodontal ligament. The name of the fascicular bone is associated with the Sharpei fibers and numerous perforations that lead to the formation of vascular and nerve elements, therefore it is called a crypt-like plate.

Cancellous bone Located between the cortical plate and the fascicular bone. It occupies the middle of the alveolar processes and is trabecular in nature. Cortical plate It is located on the surface of the alveolar processes and extends from the alveolar ridge to the lower limits of the alveoli. It is finely fibrillated thin bone composed of longitudinal lamellae, Havers canals, which together form Haversian thickness systems that vary considerably.

1. Organization of the class:

I enter. Hello. Checking attendance. Inform the topic of the lesson and the plan of work for the lesson.

2. Checking homework:

Retelling of the topic “Organoids of the cell. Chemical composition cells "and independent work (Book with assignments for individual work, grade 8, part 1, p. 6)

3. Learning new material.

Vulcanization of alveolar processes

Functions of alveolar processes

Signs that may occur at the periodontal level. Changes in the contours of the gums, which can occur in the form of: recession, true or false periodontal pockets, fracture lesions. They are caused by swelling and swelling of the mucous membranes of the gums or a decrease in the volume of the resin.

Volume changes in the gingival mucosa. Volume reduction, which may be physiological or pathological. Physiological due to the aging process, and pathological due to dystrophic forms of periodontopathy. The increase in volume is associated with hyperplasia and hypertrophy of the gums.

In the body of humans and animals, individual cells or groups of cells, adapting to the performance of various functions, differentiate, i.e. change their forms and structure accordingly, remaining at the same time interconnected and subordinated to a single integral organism. This process of continuous development of cells leads to the emergence of many different types of cells that make up human tissues.

You know that the human body, like all living organisms, consists of cells. The cells are not arranged randomly. They are connected by intercellular substance, grouped and form tissues. Tissue is a collection of cells that are identical in origin, structure and functions. Tissues are divided into 4 groups: epithelial, connective, muscle and nervous.

Epithelial tissue (from Greek epi - surface), or epithelium, forms the top layer of the skin (only a few cells thick), the mucous membranes of internal organs (stomach, intestines, excretory organs, nasal cavity), as well as some glands. Epithelial tissue cells are closely adjacent to each other. Thus, it performs a protective role and protects the body from getting into it. harmful substances and microbes. Cell shapes are varied: flat, tetrahedral, cylindrical, etc. The structure of the epithelium can be single-layer and multilayer. So, the outer layer of the skin is multi-layered. When it is peeling, the upper cells die off and are replaced by internal, following ones.

Depending on the function performed, the epithelium (Fig. 3) is divided into the following groups:

glandular epithelium - cells secrete milk, tears, saliva, sulfur;

ciliated epithelium respiratory tract traps dust and other foreign bodies with movable cilia. Hence its other name - ciliated;

stratified integumentary epithelium covers the surface of the skin and the oral cavity, lines the esophagus from the inside; single-layer tetrahedral (cubic) - lines from the inside renal tubules; cylindrical - lines the stomach and intestines from the inside;

sensitive epithelium perceives excitation. For example, the olfactory epithelium of the nasal cavity is very sensitive to odors.

Functions of epithelial tissue:

1) protects underlying tissues;

2) regulates the constancy of the internal environment of the body;

3) participates in the metabolism at the initial and final stages;

4) regulates metabolism, etc.

Connective tissue. Connective tissue forms blood, lymph, bones, fat, cartilage, tendons, ligaments. By structure, the connective tissue is divided into dense fibrous, cartilaginous, bone, loose fibrous, blood and lymph (Fig. 4).

Dense fibrous tissue - cells are located close to each other, a lot of intercellular substance, a lot of fibers. It is located in the skin, in the walls of blood vessels, ligaments and tendons.

Cartilage - cells are spherical, arranged in bundles. There is a lot of cartilage tissue in the joints, between the bodies of the vertebrae. The epiglottis, pharynx and auricle also consist of cartilaginous tissue.

Bone. It contains calcium salts and protein. Cells of bone connective tissue are alive, they are surrounded by blood vessels and nerves. The structural unit of bone tissue is the osteon. It consists of a system of bone plates in the form of cylinders inserted into each other. Between them are bone cells - osteocytes, and in the center - nerves and blood vessels. Skeletal bones are composed entirely of such tissue.

Loose fiber fabric. The fibers are intertwined with each other, the cells are located close to each other. Surrounds blood vessels and nerves, fills the space between organs. Connects skin to muscles. Under the skin, it forms a loose tissue - subcutaneous adipose tissue.

Blood and lymph are fluid connective tissue.

Connective tissue functions:

1) gives strength to tissues (dense fiber fabric);

2) forms the basis of tendons and skin (dense fibrous tissue);

3) performs a supporting function (cartilage and bone tissue);

4) provides transportation throughout the body of nutrients and oxygen (blood, lymph).

4. Watch a video clip

Disk "Human Anatomy"

5. Homework

(paraphrase of § 7)

6. Lesson summary and grading.

What conclusion did you draw at the end of our lesson?

Tissues are a collection of cells and non-cellular structures (non-cellular substances) that are similar in origin, structure and functions. There are four main groups of tissues: epithelial, muscle, connective and nervous.

… Epithelial tissues cover the body from the outside and line the hollow organs and walls of the body cavities from the inside. A special type of epithelial tissue - glandular epithelium - forms most of the glands (thyroid, sweat, liver, etc.).

... Epithelial tissues have the following features: - their cells are closely adjacent to each other, forming a layer, - there is very little intercellular substance; - cells have the ability to restore (regenerate).

… Epithelial cells in shape can be flat, cylindrical, cubic. According to the number of layers of the epithelium, there are single-layer and multilayer.

... Examples of epithelium: a single-layer squamous lining the thoracic and abdominal cavity body; multilayer flat forms the outer layer of the skin (epidermis); single-layer cylindrical lines most of intestinal tract; multilayer cylindrical - the cavity of the upper respiratory tract); a single-layer cubic forms the tubules of the nephrons of the kidneys. Functions of epithelial tissues; borderline, protective, secretory, absorption.

CONNECTIVE TISSUE PROPERLY CONNECTIVE SKELETAL Fibrous Cartilaginous 1. loose 1. hyaline cartilage 2. dense 2. elastic cartilage 3. formed 3. fibrous cartilage 4. unformed With special properties Bone 1. reticular 1. coarse fibrous 2. fatty 2. lamellar aya: 3. mucosa compact substance 4. pigmented spongy substance

... Connective tissues (tissues of the internal environment) combine groups of tissues of mesodermal origin, very different in structure and functions. Types of connective tissue: bone, cartilage, subcutaneous fatty tissue, ligaments, tendons, blood, lymph, etc.

... Connective tissues A common characteristic feature of the structure of these tissues is a loose arrangement of cells separated from each other by a well-defined intercellular substance, which is formed by various fibers of protein nature (collagen, elastic) and the main amorphous substance.

... Blood is a type of connective tissue in which the intercellular substance is liquid (plasma), due to which one of the main functions of blood is transport (carries gases, nutrients, hormones, end products of cell vital activity, etc.).

... The intercellular substance of loose fibrous connective tissue, located in the layers between organs, as well as connecting the skin with muscles, consists of an amorphous substance and elastic fibers freely located in different directions. Due to this structure of the intercellular substance, the skin is mobile. This tissue performs supporting, protective and nourishing functions.

... Muscle tissues determine all types of motor processes within the body, as well as the movement of the body and its parts in space.

… This is ensured by special properties muscle cells- excitability and contractility. All muscle tissue cells contain the thinnest contractile fibers - myofibrils, formed by linear protein molecules - actin and myosin. When they slide relative to each other, the length of the muscle cells changes.

... Striated (skeletal) muscle tissue is built from many multinucleated fiber-like cells 1-12 cm long. All skeletal muscles, muscles of the tongue, walls of the oral cavity, pharynx, larynx, upper esophagus, mimic, diaphragm are built from it. Figure 1. Striated fibers muscle tissue: a) the appearance of the fibers; b) cross section of fibers

... Features of striated muscle tissue: speed and arbitrariness (i.e., the dependence of contraction on the will, desire of a person), the consumption of a large amount of energy and oxygen, fast fatiguability. Figure 1. Fibers of striated muscle tissue: a) appearance of the fibers; b) cross section of fibers

… Cardiac tissue consists of transversely striated mononuclear muscle cells, but has different properties. The cells are not arranged in a parallel bundle, like skeletal cells, but branch, forming a single network. Due to the many cellular contacts, the incoming nerve impulse is transmitted from one cell to another, providing simultaneous contraction and then relaxation of the heart muscle, which allows it to perform its pumping function.

... Cells of smooth muscle tissue do not have transverse striation, they are fusiform, single-nuclear, their length is about 0.1 mm. This type of tissue is involved in the formation of the walls of tube-shaped internal organs and vessels (digestive tract, uterus, Bladder, blood and lymph vessels).

... The nervous tissue from which the brain and spinal cord, nerve nodes and plexuses are built, peripheral nerves, performs the functions of perception, processing, storage and transmission of information coming from both environment, and from the organs of the body itself. The activity of the nervous system provides the body's reactions to various stimuli, regulation and coordination of the work of all its organs.

... Neuron - consists of a body and processes of two types. The body of a neuron is represented by the nucleus and the cytoplasm surrounding it. It is the metabolic center of the nerve cell; when it is destroyed, she dies. The bodies of neurons are located mainly in the brain and spinal cord, i.e., in the central nervous system (CNS), where their accumulations form the gray matter of the brain. Clusters of nerve cell bodies outside the CNS form nerve ganglia, or ganglia.

Figure 2. Various shapes of neurons. a - a nerve cell with one process; b - nerve cell with two processes; c - a nerve cell with a large number of processes. 1 - cell body; 2, 3 - processes. Figure 3. Scheme of the structure of a neuron and nerve fiber 1 - body of a neuron; 2 - dendrites; 3 - axon; 4 - axon collaterals; 5 - myelin sheath of the nerve fiber; 6 - terminal branches of the nerve fiber. The arrows show the direction of propagation of nerve impulses (according to Polyakov).

... The main properties of nerve cells are excitability and conductivity. Excitability is the ability of the nervous tissue in response to irritation to come into a state of excitation.

... conductivity - the ability to transmit excitation in the form nerve impulse another cell (nerve, muscle, glandular). Due to these properties of the nervous tissue, the perception, conduction and formation of the body's response to the action of external and internal stimuli is carried out.

The human body is a certain integral system that can regulate itself independently and periodically recover if necessary. This system, in turn, is represented by a large set of cells.

On cellular level very important processes are carried out in the human body, which include metabolism, reproduction, and so on. In turn, all cells of the human body and other non-cellular structures are grouped into organs, organ systems, tissues, and then into a full-fledged organism.

A tissue is a union of all cells in the human body and non-cellular substances that are similar to each other in terms of their functions, appearance, education.

Epithelial tissue, better known as epithelium, is the tissue that is the basis of the surface of the skin, serosa, cornea eyeball, digestive, genitourinary and respiratory systems, genital organs, it also participates in the formation of glands.

This tissue is characterized by a regenerative feature. Numerous types of epithelium differ in their appearance. The fabric can be:

• Multilayer.
• Provided with a stratum corneum.
• Single layer, equipped with villi (renal, coelomic, intestinal epithelium).

Such a tissue is a border substance, which implies its direct participation in a number of vital processes:

1. Through the epithelium, gas exchange occurs in the alveoli of the lungs.
2. From the renal epithelium, the process of excretion of urine occurs.
3. Nutrients are absorbed into the lymph and blood from the intestinal lumen.

The epithelium in the human body performs the most important function - protection, it, in turn, is aimed at protecting the underlying tissues and organs from various kinds of damage. In the human body, a huge number of glands are created from a similar basis.

Epithelial tissue is formed from:

• Ectoderm (covering the cornea of ​​​​the eye, oral cavity, esophagus, skin).
• Endoderm (gastrointestinal tract).
• Mesoderm (organs of the urogenital system, mesothelium).

The formation of epithelial tissue occurs at the initial stage of embryo formation. The epithelium, which is part of the placenta, is directly involved in the exchange of necessary substances between the fetus and the pregnant woman.

Depending on the origin, epithelial tissue is divided into:

• Skin.
• Intestinal.
• Renal.
• Ependymoglial epithelium.
• coelomic epithelium.

These types of epithelial tissue are characterized by the following features:

1. Epithelial cells are presented in the form of a continuous layer located on the basement membrane. Through this membrane, epithelial tissue is saturated, which does not contain blood vessels in its composition.
2. The epithelium is known for its restorative properties, the integrity of the damaged layer after a certain time period is fully regenerated.
3. The cellular basis of tissue has its own polarity of structure. It is associated with the apical and basal parts of the cell body.

Within the whole layer between neighboring cells, the connection is formed quite often with the help of desmos. Desmos is a numerous structures of very small sizes, they consist of two halves, each of them in the form of a thickening is superimposed on the adjacent surface of neighboring cells.

The epithelial tissue has a coating in the form of a plasma membrane containing organelles in the cytoplasm.

Connective tissue is presented in the form of fixed cells, called:

• Fibrocytes.
• Fibroplasts.

Also in this type of tissue contains a large number of free cells (wandering, fat, fat, and so on). Connective tissue aims to give shape to the human body, as well as stability and strength. This type of tissue also connects the organs.

Connective tissue is divided into:

• Embryonic- formed in the womb. Blood cells, muscle structure, and so on are formed from this tissue.
• Reticular-consists of reticulocyte cells that accumulate water in the body. The tissue is involved in the formation of antibodies, this is facilitated by its content in the organs of the lymphatic system.
• Interstitial- the supporting tissue of organs, it fills the gaps between internal organs in the human body.
• elastic- is located in the tendons and fascia, contains a huge amount of collagen fibers.
• Adipose- is aimed at protecting the body from heat loss.

Connective tissue is present in the human body in the form of cartilage and bone tissues that make up the human body.

The difference between epithelial tissue and connective tissue:

1. Epithelial tissue covers organs and protects them from external influences, while connective tissue connects organs, transports nutrients between them, and so on.
2. In the connective tissue, the intercellular substance is more pronounced.
3. Connective tissue is presented in 4 types: fibrous, gel-like, rigid and liquid, epithelial in the 1st layer.
4. Epithelial cells resemble cells in appearance; in the connective tissue they have an elongated shape.