Unit 3: Teacher Notes

Lesson 3.1: Introduction to Energy (Optional)

Activity 3.1.1 Resources for Life

Activity 3.1.2 The Rule of Threes

Lesson 3.2: Food

Activity 3.2.1 Action Molecules

Project 3.2.2 Digestive System Design

Project 3.2.3 Living in a Material World (Optional)

Project 3.2.4Investigating Enzyme Action

Activity 3.2.5 Metabolism – A Balancing Act

Activity 3.2.6 In Search of Energy

Lesson 3.3: Oxygen

Activity 3.3.1 Gasping for Air

Activity 3.3.2 Measuring Lung Capacity

Activity 3.3.3 Rx – Understanding Prescriptions

Activity 3.3.4 Respiratory Therapy

Lesson 3.4: Water

Activity 3.4.1 Hook Up the Plumbing

Activity 3.4.2 Spotlight on the Kidney

Project 3.4.3 The Blood/Urine Connection

Activity 3.4.4 Water Balance

Activity 3.4.5 Urinalysis

Lesson 1

This lesson is meant to engage students in a discussion about power in the human body. The two activities in this lesson can be completed as described or the teacher can use elements of the activities as a quick classroom engagement discussion.

The teacher may want to engage the class with photos, video clips, or stories that showcase people pushing their bodies to the limit. The story of Mauro Prosperi has been included in the Purpose of Activity 3.1.1 as an example. Additional information on Mauro Prosperi can be found in the book Surviving the Extremes: What Happens to the Body and Mind at the Limits of Human Endurance by Kenneth Kamler, MD. The National Geographic Channel’s series Expeditions to the Edge featured Mauro’s story in the episode Sahara Nightmare. Please see the National Geographic site at for additional information about the availability of the episode.

The students will delve deeper into the book Surviving the Extremes: What Happens to the Body and Mind at the Limits of Human Endurance by Kenneth Kamler, MD in Unit 6, but you may want to consider assigning chapters to the class as they work through the activities in the next few units. The readings provide great discussion topics for issues of power and movement in the body. “Surviving the Extremes - Discussion Questions” can be used to review content, ignite discussion, and further illustrate the interactions of the human body systems.

If using this lesson as engagement, consider introducing the case of Mauro Prosperi and completing the chart described in Activity 3.1.1 as a class brainstorm on the board. Have the class list the main resources for life (food, water, and oxygen) and brainstorm functions of these fuels, the body systems that may be involved with processing or delivering these fuels, as well as environmental and personal factors that could impact availability and utilization of each. As a class, rank the resources discussed in order of importance for the body, thinking about which would run out first. Use the Conclusion questions for Activity 3.1.1 to help lead the discussion. If desired, ask students to estimate how long a person could last without each key resource (as outlined in Activity 3.1.2). Compare classroom estimates with the “Rule of Threes” and discuss factors that might impact this rule. Remind students that in this unit, they will discuss each of the resources that power the human body as well as investigate the systems of the body that work to process and deliver these key fuels.

Activity 3.1.1(Optional) – see general Lesson 1 note about using this activity as engagement

In this activity, students will begin to brainstorm the resources humans need to live, as well as the function food, water, and oxygen play in keeping a person healthy. Food serves as a source of energy for the body as well as a source of fat and insulation. This fat cushions organs and protects the human body. Water helps regulate body temperature, moistens tissues in the eyes, mouth and nose, lubricates joints, dissolves minerals and nutrients to make them accessible to the body, flushes out waste products and helps deliver nutrients and oxygen to cells. Oxygen is required to feed the body’s tissues and produce ATP in aerobic cellular respiration. The physical act of breathing assists with gas exchange and the removal of harmful gases from the body. Students will further investigate the way in which the body distributes, processes and utilizes food, oxygen and water in the next three lessons and will revisit the idea of energy as it relates to sports and movement in Unit 4. Students will also return to explore how all body systems are affected by extreme environments in the final unit.

Activity 3.1.2 (Optional) - see general Lesson 1 note about using this activity as engagement

This activity is simply an extension of Activity 3.1.1. Students will compare their estimates to a general “rule” for how long a person can survive without vital resources. The Rule of Threesis referenced in survival handbooks and various adventure sports and military websites. This “rule” is one estimate on the power of the body’s resources and is used merely as an engagement point. Students will quickly see that this estimate is not an absolute. Students have probably already come to the conclusion that factors in the environment and factors unique to the person (overall health, age, weight, will and determination, etc.) directly relate to how long a particular fuel will last. They will list these factors and use this knowledge to write a disclaimer to go under the rule. Students will further explore how the body deals with food, oxygen, and water in the upcoming lessons.

The Discovery Channel video clip can be viewed on the Internet or on the “Strength” DVD. The clip shows how an elite athlete’s body manages a fuel crisis and sets the stage for a discussion on macromolecules in food as a source of energy.

Lesson 2

Activity 3.2.1

Students will be using a variety of materials to create a model of the lock and key and induced fit model of enzyme function. The list of materials provided can be changed or expanded as there are many ways to make the models. In Part A you may want to review with the students the use of the Inspiration software and the outlining techniques used to create the concept maps by developing a short review lesson.

There is a sample outline and concept map provided. These designs are meant to be samples as there are many ways to create both the outline and the map.

Materials for 3-D Modeling Kits:

  • 1 Styrofoam ball
  • 1 Styrofoam square
  • 1 12 cm piece of wire
  • 1 8 cm2 piece of modeling clay
  • 1 colored marker
  • 1 20 cm2 piece of construction paper
  • 2 Pipe cleaners
  • Glue

Project 3.2.2

In this project, students will work in teams to research the components of the digestive system and design a model of this system on their manikens. Students will work in teams of four to formulate the design. They can either work together to build one completed model on one of the two manikens in the team or if time permits, each pair should build the digestive system on their own maniken. Provide clay in all available colors and encourage students to use additional modeling materials and materials from home to add texture or specific structure to the model. Stress that the materials that make up the structures of the digestive system are highly related to their function in the body. Check to make sure that the organs placed on the maniken are connected in an appropriate order and that placement is consistent with true anatomy. Provide reference textbooks or suggest helpful websites that display true digestive system anatomy.

One basic assembly for the maniken digestive system is shown and described below. These building photographs are presented simply as a guideline. This activity should not be a teacher-led building activity. Students should customize the design using clay and other modeling materials and figure out connections and placement on their own. You may want to provide students with the hint that it may be easier to first sculpt all of the organs on the gastrointestinal tract and then go back and add any accessory organs.

Students can build the palate, the roof of the mouth, above the mouth and below the nasal cavity. A projection of this tissue known as the uvula hangs down from the middle of the soft palate over the roof of the tongue. In this model, the palate and uvula are shown in white and the tongue has been constructed in terra cotta clay. Remind students that the tongue is a very powerful muscle. The tongue extends back to the hyoid bone, its bony attachment. Students may want to add salivary glands and teeth to the oral cavity. The pharynx directs food into the esophagus and sits directly behind the palate and the tongue (it is the open space you see when you open up and say “ahh”). The tube runs from the mouth and halfway down the neck where it becomes the esophagus. In this model, the pharynx and the esophagus are shown in pink. Make sure to hollow out a funnel at the top of the pharynx to show the opening of the cavity.

Build the J-shaped stomach and attach the organ on the left side of the abdominal cavity. The esophagus pipes directly into the stomach. The pylorus, the region of the stomach that attaches to the duodenum, points over to the side under the rib cage. In this model, the stomach has been sculpted in pink clay.

The duodenum, the first part of the intestine, attaches to the pylorus and forms a letter “C” so it can curve around the head of the pancreas. All of the organs of the GI tract can be constructed in the same color of clay to show the direct pathway of food. In this model, the small intestine has been constructed out of blue clay for emphasis. Mixed clay from the previous year also makes great intestines.

Humans have approximately 18 - 20 feet of small intestine. Use a clay extruder or roll out thick spaghetti stands for the remainder of the small intestines. About 6-8 feet of intestine was used to construct the organ in the picture below. Consider having the students measure out this length and marvel and how it could possibly fit inside the abdominal cavity. Twist the long strand back and forth to create the remaining two parts of the intestine, the jejunum and the ileum. Attach the twisted intestine to the end of the duodenum and fill the abdominal cavity with the organ. Secure the intestine on the back support and on the ilium of the pelvic bone.

Roll out a thicker tube to represent the large intestine. Approximately 14-16 inches of orange clay was used to create the intestine shown below. Attach the ileum of the small intestine to the cecum of the large intestine. The cecum is shown as a thicker pouch at the beginning of the large intestine. Wrap the intestine upward to represent the ascending colon, wind the clay across the abdominal cavity to form the transverse colon, and bend the clay downward to represent the descending colon. Bring the clay back behind the small intestine and next to the sacrum to represent the rectum and the anus.

The pancreas is then constructed using yellow clay. The organ takes the shape of a sideways comma. Reinforce that this organ is part of the digestive system, supplying enzymes needed to break down food, and part of the endocrine system, producing the hormone insulin. The pancreas fits inside the “C” shape of the duodenum and extends across the abdomen. You may have to pick up the duodenum and hold the stomach in place to secure the pancreas.

The liver is located in the upper abdomen under the diaphragm. This large organ is constructed using terra cotta clay. A small gallbladder is assembled using green clay and is placed in the hollowed-out underside of the liver.

NOTE: The digestive system will most likely have to be removed from the maniken when assembling the urinary system. Challenge the students to figure out how these two systems are actually oriented in the human body. You may also want to discuss placement of the reproductive organs.

Consider using plastic wrap to secure the entire digestive system and to help move the organs out of the way as needed. Remind students that this layer could represent the parietal peritoneum that holds the massive set of organs in place.

Each group should be assigned a different “bite of food.” Use foods that are representative of different macromolecules. Possible items include bread, butter, steak or other protein, candy, or celery (to discuss hard to digest foods high in cellulose). As students give their presentations and trace the path of their bite of food, the class should see the fate of all types of macromolecules and begin to appreciate the specificity of enzymes in the digestive tract. Students may use toothpick flags to label the location and function of key digestive enzymes. These flags can be removed at the end of the activity or left in for further study.

As a possible extension, each team could also be given a specific disease or disorder and asked to alter their model to show how this state occurs and can be remedied (if possible). Examples illnesses include ulcers, gallstones, heartburn, dehydration, anorexia, or various types of cancer.

The Human X-ray Print Set includes great shots of food moving in the digestive system. X-ray 9 clearly shows the shape of the stomach. X-rays 10 and 11 show movement of a meal through the intestines over a four hour period. The teacher may want to show the class these X-rays as a wrap-up or as a conclusion to the activity. The teacher can either show these X-rays on an overhead or make copies of the documents and give them to student groups. Students should observe the anatomy and discuss what they see over time and/or should write about what they see in their lab journals. The discussion or the writing sample could serve as an informal assessment for the project. More information about what is visible in the X-rays is provided in the booklet that comes with the X-ray set.

Project 3.2.3 (Optional Alternative to Project 3.2.2)

This optional alternative to Project 3.2.1 covers the same concepts, but asks the students to working digestive system model that is not assembled on the maniken. The focus on the lesson is material science engineering and the students are asked to choose materials for the model that mimic the properties of actual digestive organs and structures. This project may take longer to complete and does not involve the manikens.

In this project, students can use the Twelve Step Design Process to focus their overall design. They do not have to take detailed notes on each step in their lab journal, but they should follow the steps as a guide. Remind students of the steps that go into designing any sort of model or unique new product. Have the class brainstorm other potential uses for a working material science model of the human digestive system. Alternatively, instruct the students to follow through each step of the design process and take formal notes at each step. Focus should be placed on evaluating the materials that are picked for each area of the model.

The teacher should have modeling materials available in the classroom, but the students will most likely be bringing in specific items from home. Some suggested materials to have in the classroom are modeling clay, foam, various types of hoses, tubing of different diameters, straws, scraps of material, plastic wrap, pillow stuffing, thread and needles, balloons of all sizes, bubble wrap, carpet scraps, tin foil, paint, markers, glue, string, pipe cleaners and wire. Dishwashing detergent would be a good way for the student to represent bile and its role as an emulsifier. Balloons or stretchy fabric would be a good material to demonstrate the elastic properties of the stomach. Additional possibilities are listed below, but allow students to really think outside of the box and come up with their own creative materials.

Oral cavity / Styrofoam ball, balloon
Pharynx / Styrofoam ball
Salivary gland / Tiny latex balloons
Uvula / Modeling clay
Tongue / Sponge, red clay with grape nuts
Teeth / White Chicklets, small gravel
Esophagus / “animal making” balloons, tubing
Stomach / Hot water bottle, whoopee cushion, balloon
Small intestine / Slinky (with tissue paper wrap), Twizzlers, white nebulizer hose
Large intestine / Soaker hose, vacuum hose, irrigation pipe, nerd rope, dialysis tubing, sausage casing, slinky in panty hose
Pancreas / Sponges, tubing, utility glove (finger portion), feather, Floam
Liver / Pancake, open-cell foam
gallbladder / Green balloon
ducts / 2-hole rubber stopper, aquarium tubing and Y-junctions, old electric cords/ mouse cords

Each group should be assigned a different “bite of food.” Use foods that are representative of different macromolecules. Possible items include bread, butter, steak or other protein, candy, or celery (to discuss hard to digest foods high in cellulose). As students give their presentations and trace the path of their bite of food, the class should see the fate of all types of macromolecules and begin to appreciate the specificity of enzymes in the digestive tract.