Abstract on the structure and functions of the kidneys. Lesson "structure and function of the kidneys". Lesson using reference notes

Sections: Biology

Class: 8

Lesson objectives: reveal the role of excretion in maintaining the constancy of the internal environment of the body; to acquaint with the main ways of excretion of metabolic products in the human body; to form ideas about the structure and functions of the organs of the urinary system: kidneys, bladder, ureters and urethra; about the features of the kidneys; on the regulation of urination. To reveal the consequences of impaired kidney function, to show the causes of urinary diseases and the basics of their prevention.

Lesson plan:

Organizing time.

Updating and checking knowledge.
Conversation with students about the role of metabolism in the body.

Learning new material.

Introduction by the teacher.

In the process of metabolism, decay products are formed. Some of these products are used by the body, others are removed from it. Carbon dioxide, water, volatile substances are removed from the body through the lungs. The intestines secrete some salts, sweat glands - water, salts, organic substances. The main role in excretory processes belongs to the kidneys. The kidneys remove water, salts, ammonia, urea, and uric acid from the body. Through the kidneys, many foreign and poisonous substances that are formed in the body or taken in the form of medicines are removed from the body. The kidneys contribute to maintaining the constancy of the composition of the internal environment of the body. Excess water or salts in the blood can cause changes in osmotic pressure, which is dangerous for the vital activity of the cells of our body. The kidneys remove excess water and mineral salts from the body, restoring the constancy of the osmotic properties of the blood. The kidneys maintain a certain constant reaction of the blood. With the accumulation of acidic or alkaline metabolic products in the blood through the kidneys, the excretion of excess salts increases. In maintaining the constancy of the blood reaction, a very important role is played by the ability of the kidneys to synthesize ammonia, which binds acidic products, replacing sodium and potassium in them. In this case, ammonium salts are formed, which are excreted in the urine, and sodium and potassium are stored for the needs of the body.

Student's message "How is the excretion of waste products in unicellular and multicellular organisms."

The urinary system consists of the urinary organs and the urinary organs. The urinary organs include the kidneys, and the urinary organs include the ureters, bladder, and urethra.

The kidneys are paired, bean-shaped organs located in the abdominal cavity. The weight of the kidneys is 320 grams. The kidneys are a biological filter. The right kidney is lower than the left one. Beneath the kidneys is the liver, the largest gland in our body. Outside, the kidney is covered with a strong elastic capsule.

Rice. 2

The ureters leave the kidney. The length of the ureters is 30 cm. Urine flows smoothly along them into the bladder. Every 7 seconds, another portion of urine comes out of the kidneys. The bladder is an unpaired organ with a capacity of 300-500 ml. The excretion of urine occurs reflexively. This reflex is developed by 2-3 years.

Microscopic structure of the kidneys:

The structural unit of the kidney is the nephron. There are about 1 million of them in each kidney. Nephron can be figuratively compared with a pearl, the scattering of which figuratively stores a kidney or a precious filter embedded in a simple mouthpiece. On top of the kidney is covered with a cortical layer, and below it is the medulla. It contains capsules of Shumlyansky, similar to glasses. In the glasses there is a capillary glomerulus, which is surrounded by Bowman's capsule, which passes into the renal tubule.

Rice. 3

Blood supply to the kidneys:

The kidney gives us a "wonderful network of arteries." Nowhere in the body is there such a sequence of vessels: artery, capillary, artery. Urine is formed in the nephron. Urine formation occurs in 2 stages:

The composition of urine is determined by the state of the body. If a person has diabetes, then sugar appears in his urine. If the food is rich in carbohydrates, then after hard physical work, sugar may appear in the urine. The kidneys synthesize biologically active substances (renin is an enzyme involved in biochemical processes). In total, 1.5 liters of urine is formed per day.

Independent work.

Students are given forms with an analysis of the urine of an imaginary patient. Task for students - are there any deviations in urine tests? ( Appendix 2) The results are recorded in the table:

The kidneys are a vital organ and a malfunction in their work leads to kidney diseases.

Renal diseases: enuresis, pyelonephritis, cystitis, urolithiasis. Enuresis - urinary incontinence; cystitis - inflammation of the bladder; pyelonephritis - inflammation of the renal pelvis.

Disease prevention requires adherence to certain hygiene rules: proper nutrition, timely dental treatment, sore throats, hardening, careful handling of drugs, poisons, personal hygiene.

They're like two big beans
Attached to the links.
At the spinal column
Cozy accommodations.
The kidneys filter our blood
With unparalleled stubbornness,
So that in the internal environment
There was constancy.
Nephron contains capsules,
tubules and glomeruli
A million nephrons
Contain our kidneys.
Blood passes through the nephron
The canal decides here
What to return to the body
What does he remove?
From a young age we must take into account
What is most precious to us
We must protect not only honor,
But so are our kidneys.

4. Consolidation of the studied material.

Questions for students:

Is it related to the urinary system?

What organs are the urinary organs?

Why are the kidneys called biological filters?

What is a nephron? How is it arranged? How does it work?

How is urine formed?

Causes of kidney disease?

How to prevent kidney disease?

5. Homework: P.41, 42.

Literature:

V.V. Pasechnik, G.G. Shvetsov Biology lessons. 8th grade. Moscow “Enlightenment” 2010

R.D. Mash, A.G. Dragomilov Biology. Human. Grade 8 Moscow “Venta – Graf” 2006

R.D. Mash. Man and his health. Moscow. 1996

V.V. Kserofontova, V.V. Evstafiev. Anatomy and physiology of man. Moscow. 1996

T.V. Kozachok Biology. 8th grade. Volgograd. 2004

Klyukina Olga Vladimirovna, teacher of chemistry and biology, MAOU Bannikovskaya secondary school

Biology, grade 8

Subject: The structure and function of the kidneys

Educational: To form knowledge about the structure of the urinary system. To reveal the features of the structure and location of the kidneys in the body.

Developing: Develop logical thinking. Establish patterns between the structure of an organ and its functions.

Educational: Education of a conscious attitude to one's health, personal hygiene.

Dragmilov A.G., Mash R.D. Biology: Human Textbook for students grade 8 of educational institutions. - 2nd ed., Revised. - M .: Ventana - Graff, 2003

Table "Human excretory organs", model "Structure of the kidney",

Collection of tasks in biology GIA-2014. Moscow Exmo 2013.

Welcome speech of the teacher Updating the material covered Determining the topic of the lesson Learning new material Primary consolidation of knowledge Reflection Homework . Move on to the topic of the next lesson.

During the classes.

A) two students work at the blackboard. (The first student draws up a metabolic diagram based on the key concepts written in the notebook at the last lesson. The second student draws up a diagram of the transformation of food as it passes through the digestive tract, and talks about the end products of the breakdown of the basic substances of the cell).

IN) Work with the class: test work on the topic covered, after the work is completed, they are submitted for verification to the teacher

Checking the work of students at the blackboard:

Questions for the first student: What is the importance of metabolism. Where do metabolic processes take place? in a cage), is there a relationship between anabolism and catabolism, what? (these processes are inseparable and take place in the cell simultaneously, the energy received during catabolism is consumed during anabolism).

Questions for the second student(the class helps in case of difficulty) - how is the food bolus transformed? What happens to the end products? ( the body uses nutrients, some of the substances are removed from the body.)

How is the delivery of the necessary substances to cells and how is the removal of harmful substances from the body? What organs are involved in the excretion process? (Intestines, lungs, kidneys, skin)

Determining the topic of the lesson

We are familiar with the work of the intestines and lungs, what task we face today, but before answering the question, let's analyze the table. (Appendix)

Which organs remove the largest amount of various substances from our body. (kidney). Students determine the topic of the lesson and write it down in their notebook.

Learning new material.

Guys, look at the data in the table, and formulate a definition for the concept " Selection». ( It is the process of removing unnecessary and harmful substances from the body.).

The excretion process is carried out by the urinary system. Using Fig. 69 on page 157, draw a diagram of the urinary system. ( kidneys - ureters - bladder - urethra)

The story of the teacher "The structure of the kidneys", (accompanied by explanations on the model. In the course of the story, the teacher draws the attention of the children to key points, the children make notes in a notebook).

The main organs of the excretory system are the kidneys: This is a paired bean-shaped organ.

In humans, the kidneys are located in the lumbar region. on the sides of the last two thoracic and first two lumbar vertebrae. Adjacent to the posterior abdominal wall, and the right kidney is normally located somewhat lower, since from above, it borders on the liver. The dimensions of one kidney are approximately 11.5-12.5 cm long, 5-6 cm wide and 3-4 cm thick. The mass of the kidneys is 120-200 g, usually the left kidney is slightly larger than the right one.

In each kidney, a cortical and medulla layer, and a renal pelvis are distinguished . The renal pelvis passes directly into the ureter. The right and left ureters empty into the bladder. Morpho - functional unit of the kidney is nephron - a specific structure that performs the function of urination . Each kidney has over 1 million nephrons.

Each nephron consists of several parts: glomerulus, Shumlyansky-Bowman's capsule and a system of tubules, passing one into another.

The story of the teacher "Formation of urine", (accompanied by explanations on the table. In the course of the story, the teacher draws the attention of the children to key points, the children make notes in a notebook).

The process of making urine and removing it from the body is called diuresis.

This is a very complex process, it is closely related to the blood supply to the kidneys, which is many times greater than the blood supply to other organs. This ensures the purification of the blood from substances continuously entering it from the cells to be removed from the body with urine.

Diuresis occurs in two stages (phases). (Depicted as a cluster)

1. Filtration - substances brought by blood into the capillaries of the glomerulus are filtered into the cavity of the nephron capsule. This is due to a significant pressure difference in the glomerulus (70 mm Hg) and in the capsule cavity (30 mm Hg).

Such a high pressure in the capillaries is provided by:

slow blood flow

high blood pressure in the afferent arteriole (renal artery departs from the aorta, where the blood is under the highest pressure).

pressure difference between afferent and efferent arterioles

The filtered liquid is called primary urine . In composition, it corresponds to blood plasma without proteins. Primary urine contains a lot of substances needed by the body (sugar, amino acids, vitamins, hormones) and they can be useful to the body, so they are not removed from the body, but substances are reabsorbed into the blood in the next phase.

2. Reabsorption - occurs when the primary urine moves through the convoluted tubules, which are tightly braided with capillaries.

Reabsorption proceeds: a) passively - according to the principle of diffusion and osmosis;

b) actively - due to the activity of the epithelium of the renal tubules with the participation of enzyme systems with energy expenditure. During reabsorption, primary urine gives the blood water, glucose, amino acids, vitamins, a significant amount of potassium and sodium ions - this ensures the constancy of the internal environment (the second function of the kidneys). Substances such as urea, ammonia, sulfates, other waste products, as well as excess, for example, glucose, are not absorbed back, their concentration in the urine along the tubules increases, and secondary urine, which must be removed from the body (the first function of the kidneys).

In addition to reabsorption in the tubules, there is a release into their lumen of harmful substances that have entered the body and into the bloodstream from the external environment (dyes, antibiotics, sulfonamides, etc.). If these substances are not filtered into capsules, then they are removed from the blood through the capillary network that wraps around the convoluted tubule. The yellow color of urine depends on the pigment urochrome, a product of the breakdown of hemoglobin.

Task:2 Using table No. 2, answer the question: What is the difference between primary and secondary urine?

Guys, the selection process is an important and complex process. The organs that ensure its smooth operation must be healthy and this is entirely up to you. You need to lead a healthy lifestyle, observe the rules of personal hygiene. We will talk about kidney diseases and their prevention in the next lesson.

Application

Tasks for students working at the blackboard.

1 Draw up a metabolism diagram based on the key concepts written in the notebook (energy and plastic metabolism)
2.. Draws up a scheme for the transformation of food as it passes through the digestive tract, and talks about the end products of the breakdown of the basic substances of the cell).

Test work for the class

1 option

Handout

Table No. 2 The difference between primary and secondary urine

Character of urine

The structure of the kidney and nephron

Questions of reflection

Methodical materials Barkan O.Yu. MAOU Lyceum No. 102, Chelyabinsk Development of biology lessons

LESSON SUMMARY

on the implementation of problem-based learning technology
Lesson topic: The structure and function of the kidneys

8th grade

1. 
   Target: imagine the final stage of metabolism in the body, occurring in the kidneys and urinary organs.
2. 
   Tasks:

1. 
   Lead students to identify the role of the kidneys in removing decay products from the body;
2. 
   explain the functions of the kidneys and urinary organs in maintaining blood homeostasis and the internal environment of the body as a whole;

3. to promote the development of students' skills to identify and formulate a learning problem (the topic of the lesson) and find ways to solve it;

4. to continue developing the skills of students to highlight the main thing and draw a conclusion on the material studied;

Educational:

5. create a positive emotional attitude towards learning.

3. Type of lesson: the formation of new knowledge and skills

4. Logical approach: inductive

5. Methods:

General- problem-dialogical

Private- verbal visual

Specific- explanation, watching video clips, conversation.

6. Providing a lesson:

Teacher: a table depicting the system of urinary organs, kidney and nephron; video film "Excretory system", lesson summary; textbook; workbook for the textbook; prepared educational tasks.

Students: textbook; workbook for the textbook; notebook.

Literature for the teacher.

1. Dragomilov A.G., Mash R.D. Biology: Man: A textbook for students of the 8th grade of educational institutions. - 2nd ed., revised. – M.: Ventana-Graf, 2006. – 272 p.: ill. (Chapter 7. Urinary system. § 39. The structure and functions of the kidneys. pp. 157-159).

3.Mash R.D., Dragomilov A.G. Biology. Person: Grade 8: Methodological guide. - 2nd ed., revised. – M.: Ventana-Graf, 2004. – 288 p.: ill.

4. Rezanova E.A., Antonova I.P., Rezanov A.A. Human biology in tables and diagrams: Ed. E.A. Rezanova. - M .: "Publishing School", 1998. - 208 p.

Literature for students.

1. Dragomilov A.G., Mash R.D. Biology: Man: A textbook for students of the 8th grade of educational institutions. - 2nd ed., revised. – M.: Ventana-Graf, 2006. – 272 p.: ill. (Chapter 7. Urinary system. § 37. The structure and functions of the kidneys. pp. 157-159).

2. Mash R.D., Dragomilov A.G. Biology: Man: Workbook No. 2 for students in the 8th grade of educational institutions. - 2nd ed., revised. – M.: Ventana-Graf, 2005. – 80 p.: ill. DURING THE CLASSES

In the lesson, we will get an idea of ​​what excretory organs are in the human body and what they are for. Consider the structure of the kidneys, their functions. We will understand the work of the kidneys and learn about their huge role in the functioning of the body.

Excretion is the most important part of metabolism - the removal from the body of decay products that can no longer be used. Removal of decay products of nutrients that have entered the body, provides homeostasis(the constancy of the internal environment).

Removed from the body: carbon dioxide, excess water, urea, uric acid, salts and other chemicals.

Some of the excretory organs are lungs. The lungs remove carbon dioxide and some water from the body in the form of steam, as well as urea, salts and water. sweat glands skin. And the main organs of the excretory system are kidneys.

The kidneys excrete many substances from the body, namely urea, excess water, uric acid, and other chemicals.

The kidneys are paired bean-shaped organs located at the posterior wall of the abdominal cavity, at the level of the first and second lumbar vertebrae (Fig. 1).

Rice. 1. Kidneys

The mass of each kidney is about 150 grams, length is about 12 cm, width is 7 cm, thickness is 3 cm.

The kidneys are attached to the abdominal wall with a layer of connective tissue and are located on both sides of the spine, above the lower back, behind the stomach and liver (Fig. 2).

Rice. 2. Location of the kidneys

The kidney is covered with connective and adipose tissue. The concave edge of the kidney is turned towards the spine, here the blood vessels that innervate the nerves enter and exit the kidney, and the renal pelvis is also located there. The ureter departs from the renal pelvis, which connects the kidney to the bladder, which is connected to the urethra (Fig. 3).

Rice. 3. The structure of the kidneys

Rice. 4. Scheme of the urinary system

The kidney consists of two layers of a cortical outer layer (dark brown) and a medullar inner layer (light brown). These layers are interconnected by renal pyramids (Fig. 5).

Rice. 5. Layers of the kidneys

In the cortex are nephrons, and in the medulla - renal tubules(Fig. 6).

Rice. 6. The structure of the layers

Each kidney contains approximately 1 million nephrons. Nephron- structural functional unit of the kidney, providing filtration processes.

The nephron consists of the Shumyansky-Bowman capsule and the renal tubule (Fig. 8).

The capsules located in the cortical layer are microscopic cups of two layers of epithelial cells, between them there is a slit-like space, from there the renal tubules begin, inside the capsule there is a capillary glomerulus, it is formed by the repeatedly branching afferent renal artery. At the exit from the capsule, the efferent arterial vessel also branches into capillaries, which braid the walls of the tubule (Fig. 7).

Rice. 7. The structure of the nephron

The tubule that departs from the capsule is called the convoluted tubule of the first order and passes through the medulla, forming the loop of Henle, returns to the cortical layer, forming a second-order tubule, it flows into the collecting duct (Fig. 8).

Rice. 8. The structure of the tubule

The collecting ducts unite into excretory streams that pass into the renal pelvis at the tops of the renal pyramids.

The kidneys work under heavy load, in 4-5 minutes all the blood of the body is filtered through them. The blood supply to the kidneys is not the same as in other human organs. The vascular system consists of arteries - capillaries - arteries. Due to this structure, the body is quickly released from harmful substances in the form urine.

Urine is formed due to the fact that the blood through the afferent artery enters the capillary glomerulus (the afferent vessel is 2 times wider than the efferent vessel), excess blood pressure is created in the glomerulus, due to which blood is filtered into the cavity of the Shumlyansky-Bowman capsule, thus primary urine. It contains many more substances useful to the body (glucose, vitamins, amino acids, minerals) and decay products (urea, ureic acid). In an adult, about 200 liters of primary urine is formed in the nephrons per day. From the lumen of the capsules, primary urine moves along the convoluted tubule, its walls are adapted to reabsorption (reabsorption) substances contained in the primary urine (Fig. 9).

Rice. 9. Urine formation

During reabsorption, water, sodium and potassium salts, vitamins, amino acids enter the body back. Some substances enter the blood without high energy costs by osmosis and diffusion, while others, on the contrary, as a result of high energy costs. In addition to reabsorption, tubules secretion. Secretion - the entry from the blood into the urine of certain chemicals (uric acid, foreign chemicals) (Fig. 10).

Rice. 10. Secretion and reabsorption

As a result of reabsorption and secretion in the renal tubules, from the primary urine, secondary urine- a product that is to be excreted from the body.

Rice. 11. Secondary urine content

A healthy person produces 1.5-2 liters of secondary urine per day. Through the collecting ducts, secondary urine enters the renal pelvis, then through the ureters into the bladder, from which it is excreted from the body through the urethra (Fig. 12).

Rice. 12. Channels for excretion of secondary urine

Bibliography

1. Kolesov D.V. etc. Biology. Human. Textbook for grade 8. - 3rd ed. - M.: Bustard, 2002. - 336 p.
2. Vakhrushev A.A., Rodionova E.I. etc. Biology. 8th grade. (Know thyself). - M.: 2009. - 304 p.
3. Dragomilov A.G., Mash R.D. Biology. 8th grade. - 3rd ed., revised. - M.: 2008. - 272 p.
4. Sonin N.I., Sapin M.R. Biology. Human. Textbook for grade 8. - M.: 2012. - 288 p.
5. Rokhlov V.S., Trofimov S.B. Biology. Man and his health. 8th grade. - 2nd ed., erased. - M.: 2007. - 287 p.
6. Pasechnik V.V. etc. Biology. 8th grade. - M.: 2010. - 255 p.
7. Lyubimova Z.V., Marinova K.V. Biology. Man and his health. 8th grade. - M.: 2012. - 255 p.

1. Internet portal "opochkah.ru" ()
2. Internet portal "Festival of Pedagogical Ideas "Open Lesson"" ()
3. Internet portal "pedsovet.pro" ()

Homework

1. What organs of the excretory system do you know?
2. Describe the structure of the kidneys.
3. What is reabsorption and secretion?
4. What is secondary urine?

Tasks:

To form students' knowledge of the anatomical and physiological features of the urinary system.

To study the structure of the kidneys and their functions.

Continue to educate students about their own health.

Equipment: table "Structure of the urinary system", cards with group tasks, cards with a picture of a kidney, test tasks.

The course of the biology lesson in grade 8

I. Actualization of knowledge.

Having studied quite a lot of organs of our body, we often mention the term "vital organ". Today in the lesson we have to get acquainted with another organ that is part of the excretory system - the kidneys. Having become acquainted with the meaning, structure and work of the kidneys, we must confirm or refute their status as “vital organs”.

II. Learning new material.

The stages of the lesson are written on the board:

Importance of the excretory system (Group 1)

The structure of the urinary organs (group 2)

Microscopic structure of the kidney (group 3)

Blood supply to the kidney (group 4)

Urine formation (Group 5)

Unusual numbers (Group 6)

At the beginning of the lesson, students are given time to familiarize themselves with individual group tasks, and then during the lesson each group makes a small report on the material read at different stages of the lesson.

Download messages for students

1. Importance of the excretory system.

Group #1 delivers a message about the significance of the excretory system. Pay special attention to the end products excreted from the body (urea, uric acid, ammonia, ammonium salts). A card with a list of these chemicals, prepared by the students, is posted on the board. The rest are written in a notebook (Value - removal of liquid decomposition products - ammonia, urea and others).

2. The structure of the urinary organs.

Group No. 2 makes a report on the structure of the organ system. Students list the organs depicted on the poster, determine which of them are urinary and urinary, and draw up a diagram of the urinary system on the board (the rest of the students write it in a notebook).

The teacher, in the course of filling out the diagram, explains the structure of the organs (Fig. 69).

Download message about kidneys

3. Microscopic.

A student from group No. 3 talks about the structure of the kidney and shows on the poster. Another student tells and shows the structure of the nephron. Students from the textbook (p. 157) get acquainted with the structure of the nephron. Writing in a notebook (The structural unit of the kidney is the nephron).

Students work with their cards (picture of a kidney) and mark the parts of the kidney that they have listed, and then hand it over to the teacher.

4. Blood supply to the kidneys.

Group No. 4 talks about the blood supply to the nephron (according to the poster at the blackboard).

5. Formation of urine.

In the course of the story of the students of group No. 5, a table is filled in notebooks.