Objectives

(5 - 7 minutes)

1. Describe the Excretory System and its main functions:

   • Identify the organs that make up the excretory system: kidneys, ureters, bladder, and urethra.
   • Understand the role of each organ in the excretion of metabolic waste from the human body.

2. Explain the process of urine formation:

   • Understand how urine is formed in the kidneys.
   • Identify the components of urine.

3. Understand the process of urine elimination from the human body:

   • Describe how urine is conducted from the kidneys to the bladder.
   • Explain the process of micturition.

Secondary Objectives:

• Stimulate active participation of students through discussions and questions.
• Relate the learned content to real-life situations, emphasizing the importance of the excretory system for human health.
• Promote autonomous learning, encouraging students to research more about the topic after the lesson.

Introduction

(10 - 15 minutes)

1. Review of previous contents:

   • The teacher should start the lesson by briefly reviewing the human body systems already studied, such as the circulatory system and the digestive system. This review should include a recap of the functions of these systems and how they relate to the excretory system. (3 - 5 minutes)

2. Presentation of problem situations:

   • The teacher can then present two situations that arouse the students' interest in the lesson topic. The first one could be a discussion about what would happen if the body could not eliminate metabolic waste, and the second one, the reason why urine changes color when we are sick or dehydrated. (3 - 5 minutes)

3. Contextualization of the subject's importance:

   • The teacher should then explain the importance of the excretory system for human health, highlighting how its dysfunction can lead to serious problems, such as renal failure. It can also mention some curiosities, such as the fact that urine is one of the main diagnostic tools in medicine. (2 - 3 minutes)

4. Introduction of the topic:

   • To introduce the topic in an engaging way, the teacher can tell the story of how ancient Egyptians used urine for medicinal and cleaning purposes, explaining that, although it may seem strange today, it was a demonstration of their understanding of the importance of urine in human health. Another curiosity that can be mentioned is that the color of urine can vary depending on the foods we eat, such as beets, and the medications we take. (2 - 3 minutes)

Development

(20 - 25 minutes)

1. Explanation of the Excretory System:

   • The teacher should start by explaining that the Excretory System is responsible for eliminating toxic substances from the human body, produced by cellular metabolism, which if not eliminated, can impair the body's functioning. (2 - 3 minutes)
   • Next, the teacher should describe the organs that are part of the excretory system: kidneys, ureters, bladder, and urethra. For each organ, explain its location in the body, its structure, and its specific function in the excretion process. (5 - 7 minutes)
   • The teacher should emphasize that the kidneys are the main organs of the excretory system, responsible for filtering the blood and forming urine. Should explain that urine is a liquid composed of water, minerals, and toxic substances that the body needs to eliminate. (3 - 4 minutes)
   • Finally, the teacher should summarize the excretion process, explaining that urine is produced in the kidneys, passes through the ureters to reach the bladder, where it is stored until the moment of micturition, when it is eliminated from the body through the urethra. (3 - 4 minutes)

2. Urine Formation:

   • The teacher should explain in detail how urine is formed in the kidneys. Should describe the process of filtration, reabsorption, and secretion in the nephrons, the functional units of the kidneys. Should also explain that during filtration, the blood is separated from the metabolic waste that will become part of the urine. (5 - 7 minutes)
   • The teacher should then describe the components of urine, explaining that besides water, it contains minerals such as sodium and potassium, and excretion products such as urea and creatinine. Should also mention that the color and composition of urine can vary depending on factors such as hydration, diet, and the presence of diseases. (2 - 3 minutes)

3. Urine Elimination:

   • The teacher should explain how urine is conducted from the kidneys to the bladder through the ureters and how it is eliminated from the body through the urethra in the micturition process. Should also explain that micturition control is done by the nervous system, which regulates the bladder contraction and urethral sphincter relaxation. (3 - 4 minutes)

4. Practical Activity:

   • To consolidate learning, the teacher can carry out a simple practical activity. Can use an anatomical model of the excretory system to show students the location of the organs and how they are connected. Can also use graphs or diagrams to illustrate the processes of urine formation and elimination. (2 - 3 minutes)

Return

(10 - 12 minutes)

1. Group Discussion:

   • The teacher should start a group discussion with the students, addressing the following questions:
     1. What is the importance of the excretory system for human health?
     2. What would be the consequences if metabolic waste were not eliminated from the body?
     3. How is urine formed in the kidneys and what are its main components?
     4. How is urine eliminated from the human body?
   • The teacher should encourage students to share their opinions and ideas, and should clarify any doubts that may have arisen during the lesson. (5 - 7 minutes)

2. Connection to the Real World:

   • The teacher should then promote a discussion on how the excretory system is present in our daily lives and in everyday situations. For example, talk about the importance of hydration for urine production and how the color of urine can indicate if we are drinking enough water. Can also mention that urine is one of the main diagnostic tools in medicine, and that urine analysis can reveal important information about a person's health. (3 - 4 minutes)

3. Final Reflection:

   • To conclude the lesson, the teacher should propose that students reflect, in one minute, on the following questions:
     1. What was the most important concept learned today?
     2. What questions have not been answered yet?
   • The teacher can ask some students to share their answers if they feel comfortable. This final reflection helps consolidate learning and identify any gaps that may need to be addressed in future lessons. (2 - 3 minutes)

Conclusion

(5 - 7 minutes)

1. Recapitulation of Contents:

   • The teacher should summarize the main points covered during the lesson, recalling the organs that are part of the excretory system and their respective functions, the process of urine formation in the kidneys, the components of urine, and the process of urine elimination from the human body. (2 - 3 minutes)

2. Connection between Theory, Practice, and Applications:

   • The teacher should highlight how the lesson connected the theory, practice, and applications of the Excretory System. Should emphasize how theoretical knowledge about the excretory system allows understanding the functioning of the human body, and how the practical activity helped visualize this functioning. Should also mention the applications of the acquired knowledge, such as understanding how urine is formed in the kidneys can help understand the importance of hydration for health. (1 - 2 minutes)

3. Suggestion of Extra Materials:

   • The teacher should suggest extra materials for students who wish to deepen their knowledge about the Excretory System. These materials may include biology books, educational videos online, websites of health research institutions, and practical activities that students can do at home, such as building an anatomical model of the excretory system. (1 - 2 minutes)

4. Importance of the Subject for Daily Life:

   • Finally, the teacher should reinforce the importance of the excretory system for daily life, mentioning again that urine is one of the main diagnostic tools in medicine and that the color of urine can indicate if we are drinking enough water. Should also emphasize the importance of keeping the excretory system healthy, reminding students of the importance of drinking water regularly and avoiding excessive consumption of substances that can impair kidney function, such as alcohol and caffeine. (1 - 2 minutes)