Analysis of the Human Lung

 

LESSON OVERVIEW

Grade Level & Subject: Grades 5 – 8: Science

Length: One class period

Objectives:

After completing this lesson, students will be able to: 

  • State and describe the respiratory structures in humans
  • Analyze and interpret class data on breathing
  • Make a model to demonstrate how the lungs work during respiration

National Standards Addressed:

This lesson addresses the following National Education Standards:[1]

As a result of their activities in grades 5-8, all students should develop understanding of

  • Structure and function in living systems
  • Regulation and behavior

Materials Needed:

  • Stopwatch
  • Balloons
  • 2- liter plastic bottles with bottom 1/3 cut off
  • Ziploc Bags (Freezer Bags)
  • Rubber bands
  • Reproducible #1 – Model Lung Activity
  • Reproducible #2 – Human Lung Diagram

Assessment:
Students will be assessed through the following activities:

  • Participation in class discussion
  • Completion of Reproducible #1 – Model Lung Activity
  • Answers to Wrap up questions

 

LESSON BACKGROUND

Relevant Vocabulary:

  • Alveoli: A small air-containing compartment of the lungs from which respiratory gases are exchanged.4
  • Bronchi: Smalltubes that help move air into and out of the lungs.3
  • Circulatory system:The system of blood, blood vessels, and heart concerned with the circulation of the blood and lymph.7
  • Diaphragm: Muscle and connective tissue; specifically:a part of the body separating the chest and abdominal cavities in mammals.5
  • Larynx:Voice box8
  • Lung:  One of two elastic, spongy organs thatconstitute the basic respiratory organ of humans.6
  • Respiratory System:A system of organs that aid in respiration and consist of the nose, nasal passages, pharynx, larynx, trachea, bronchi, and lungs.1
  • Trachea: The main tube by which air passes to and from the lungs in vertebrates.2

1 “Respiratory System Entry.” Merriam- Webster Online Dictionary. Retrieved 2 March 2011 from http://www.merriam-webster.com/dictionary/respiratorysystem.

2 “Trachea Entry.” Merriam- Webster Online Dictionary. Retrieved 2 March 2011 from http://www.merriam-webster.com/dictionary/trachea.

3 “Bronchi Entry.” Merriam- Webster Online Dictionary. Retrieved 2 March 2011 from http://www.merriam-webster.com/dictionary/bronchi.

4 “Alveoli Entry.” Merriam- Webster Online Dictionary. Retrieved 2 March 2011 from http://www.merriam-webster.com/dictionary/alveoli.

5 “Diaphragm Entry.” Merriam- Webster Online Dictionary. Retrieved 2 March 2011 from http://www.merriam-webster.com/dictionary/diaphragm.

6 “Lung Entry.” Merriam- Webster Online Dictionary. Retrieved 2 March 2011 from http://www.merriam-webster.com/dictionary/lung.

7 “Circulatory System Entry.” Merriam- Webster Online Dictionary. Retrieved 2 March 2011 from http://www.merriam-webster.com/dictionary/circulatorysystem.

8 “Larynx Entry.” Merriam- Webster Online Dictionary. Retrieved 2 March 2011 from http://www.merriam-webster.com/dictionary/larynx.

Background Information: 

The respiratory system uses many parts for breathing in oxygen and releasing carbon dioxide.  These include the nose, the trachea, and the lungs.  First, air enters through the nose and mouth and passes through the larynx and the trachea.  Once it enters the trachea, it branches out into tubes called bronchi.  These bronchi eventually separate into tiny alveoli, which are surrounded by capillaries (tiny blood vessels).  The actual act of breathing involves two main actions:  inhaling, which pulls air into the lungs, and exhaling, which pushes air out of the lungs. Your chest can allow air in and out as a result of a muscle called the diaphragm.  The diaphragm makes up the floor of the chest cavity.  When you breathe in, your diaphragm contracts and moves down, creating more space in your chest for your lungs to fill with air. When you exhale, your diaphragm relaxes, decreasing the space in your chest and forces air out of your lungs. 

A body system that works closely with the respiratory system is the circulatory system.  This system aids in providing oxygen to all parts of the body and works with the respiratory system to carry oxygen to your cells and dissolved carbon dioxide back to your lungs. The circulatory system is the method of transportation for all the blood that is pumped into and out of your heart.

Resources:

  • LungsNational Geographic

http://science.nationalgeographic.com/science/health-and-human-body/human-body/lungs-article.html.

http://www.lungusa.org/your-lungs/

  • Fast Facts About Your BodyDid you Know?

http://didyouknow.org/fastfacts/body/

 

LESSON STEPS

Warm-up: Count your Breaths!

  1. Begin this lesson by asking students “How many times do you think you take a breath in one minute?”  -Student answers will vary, accept all answers
  2. Ask them to count how many times they take a breath in one minute while you keep track of time with a stopwatch.  Repeat this three times and ask them to calculate the average.  Post this average on the board. 
  3. Have students stand and jump up and down in place ten times.  Then, ask them to count how many times they breathe in one minute again.  Repeat this three times and ask them to calculate the average.  Post on the board.
  4. Display class data in a chart on the board.  Ask students to compare the two sets of data. 
  5. Share these facts with them: 
  6. Did you know that you breathe an average of 23,000 times a day? 
  7. On average, people can hold their breath for about one minute. The world record is 21 minutes 29 seconds
  8. Every minute, you breathe about 13 pints of air.  That is equal to approximatelyfour 2-liter bottles of soda! 

Activity One: Model your breathing

  1. Give each student a copy of Reproducible #1- Model Lung Activity.  Divide students into small groups (3 or 4 will work best).  Ask them to follow the directions on their reproducible to create a model with their group.  Make sure each group has access to balloons, 2-liter plastic bottles, rubber bands, and Ziploc bags.
  2. Give students Reproducible #2- Human Lung Diagram after they have assembled their model.  Students should use Reproducible #2 to compare and contrast their model lung with the parts in a real human lung and answer the questions on Reproducible #1.

Wrap Up:  Class Data Revisited

  1. Revisit concept by asking students to refer to chart on the board dealing with breaths per minute at rest vs. breaths per minute after activity.  Tell them to answer the following questions:  “What other factors might affect number of breaths per minute?” and “What things in the environment might make the air more difficult to breathe?”
  2. Brainstorm as a class and make a list on the board.

 

Conclusion:

Students examined and described the respiratory structures in humans, analyzed class data on breaths per minute, and built models to familiarize themselves with the workings of the human lung.  Students evaluated the strengths and weaknesses of their model as compared to a real human lung.  Students considered other factors that may affect the number of times that they breathe per minute as well as what environmental issues could cause difficulties in breathing.  Students are introduced to the fact that the respiratory system can affect the circulatory system and asked to begin thinking about environmental factors that may affect their respiratory systems.     

 

Lesson plan credits

Sharvari Chwastyk – Author

            Middle School Science Teacher, Cabin John Middle School

Maggie Ollove – Editor

            Education Associate, Earth Day Network