I. Curricular Framework

Concept:

Systems

Essential Question:

How can understanding how the Circulatory System operates relate to other human systems?

Bridge:

Flow

Content:

Blood Circulation

Outcomes:

II. Standards Aligned

III. Instruction and Assessment

1. Connect: Connecting to the Concept Experientially

Objective: To allow the students to experience a simulation of how the blood circulates through the heart, lungs, and the body.

Activity: Draw a heart with the major vessels on a large piece of butcher paper. It must be large enough to accommodate at least two students standing in each chamber of the heart. Tape it to the floor. Construct six cardboard circles, blue one side, and red on the other, with a string attached to each, to allow the students to wear it around their necks. Also tape a square of butcher paper near the heart, and label it "lungs," as well as another square below the heart labeled "body." The teacher then walks through the circuit, wearing the red/blue sign, in order to demonstrate where blood changes from red to blue, and the direction of blood flow. Choose six students at a time, to represent six red blood cells, and place one student in the lungs, one in the body, and one in each of the four chambers of the heart. Tell them this is DIASTOLE, when the heart is completely relaxed. The teacher should then call out ATRIAL SYSTOLE (when both atria of the heart contract). The students in the atria should move into the ventricles. No other students should move. Now there will be no students in the atria, two students in each of the ventricles, one student in the lungs, and one in the body. Next call out VENTRICULAR SYSTOLE (when both ventricles of the heart contract). The students in the ventricles should move into the lungs and the body (RV ñ> lungs and LV ñ> body). They should change their colors when they get there (blue ñ> red in the lungs, red ñ> blue in the body). Since the atria are now relaxed, the students who were originally in the lungs and the body move into the empty atria. Now there should be one student in each of the atria, no students in the ventricles, two students in the lungs and two students in the body. Then call out DIASTOLE. The students in the atria should move into the ventricles since the AV valves are both open when the heart is at rest. ONE of the students in the lungs can now move into the LV, and ONE of the students in the body can now move into the RV. Both students do not move since there is no forced movement caused by contraction, but only diffusion present during DIASTOLE. Notice that only during VENTRICULAR SYSTOLE do the students undergo any color changes. You might want to point out that the noise of the heart is caused by the slamming shut of the valves: the loudest noise coming during ventricular systole when the AV valves close, and the softer sound occurring during diastole, when the semilunar valves close. During this exercise, the teacher is the pacemaker and should call out ATRIAL SYSTOLE, VENTRICULAR SYSTOLE, and DIASTOLE, giving the students enough time to move to their positions. Make sure in each case, the students know what color they should be. Have each set of six students go through the complete cycle twice, and have every student in the class participate in turn.

Assessment: Quality of class interest and participation, as well as the beginning of understanding the concept.

2. Attend: Attending to the Connection

Objective: To have the students analyze what they have just done, in order to reinforce their understanding of the pattern of circulation.

Activity: Give each student an unlabeled picture of the heart. Have them label the parts of the heart and the major vessels. Have them indicate the flow of blood using arrows. Using red and blue pencils, have them indicate where the blood is oxygenated, and where it is deoxygenated. Tell them to use their textbooks as a reference.

Assessment: The accuracy of their labels.

Assessment, Phase One, Level of Engagement, Fascination:

3. Image: Creating a Mental Picture

Objective: To use guided fantasy to help students internalize the movement of the circulatory system.

Activity: The teacher will draw the shape of the bicuspid and the tricuspid valves on the board, seen in cross section. Then have the students close their eyes, breathe deeply several times and relax. Tell them they are going to experience a guided fantasy in which they will be blood cells, moving through a human body. The teacher then reads the following guided fantasy: "You are in a magic place. A friendly wizard is standing in front of you. She smiles and lifts her golden wand and suddenly you begin to shrink. You are not afraid. You know the wizard is going to allow you to have a great adventure. You are getting smaller and smaller. Suddenly you are the size of a single blood cell. You feel fine. You are lighter than air. You are buoyant and floating free. "You find yourself in a soft, blue tunnel. As you look in front of you, you notice that this tunnel is growing larger. You begin to hear a soft noise in the distance toward which you are traveling. You are moving along at a steady pace. "Lub dub, lub dub, lub dub." As you move further down the tunnel, it continues to grow larger, and the noise gets louder. "Lub dub, lub dub, lub dub." Suddenly you see a closed door in front of you. It is a double swinging door and it is opening away from you. You are carried through the door along with millions of others like you. The door closes softly behind you. You now notice that for every great sweep of motion forward, you slide back a little. The door prevents you from going backwards. There is only one way you can go, and that is forward. The door behind you is one of the valves in a vein, and you now become aware that you are inside a human body. "The noise is getting louder. "Lub dub, lub dub, lub dub." You are moving towards the noise. There is a large opening in front of you. You slide through the opening and you find yourself in a large chamber. Everything is still a soft blue around you. You notice how much bigger this space is. The walls are much thicker. They look stronger. They are slender strips intertwined. You notice there is another tunnel similar to the one you were in also leading into this chamber, but it is beneath you. You notice millions of others like you are also entering this chamber. "You suddenly become aware that you have traveled through the superior vena cava, and you are now in the right atrium of the heart. You now know that you have traveled from the head of the person whose body you are floating in. So now you know that the others like you arriving beneath where you are, are traveling through the inferior vena cava and were in the lower part of the body. "The noise is resonating through you. It is unbelievable loud. The "lub dub" is booming through your being. But it is not uncomfortable, it is exciting. You feel you are in the center of the universe. "Suddenly you feel the walls of the chamber contracting, you are being squeezed toward the only door leading out of the chamber. This door is different; you have never seen a door like this before. It has three leaves, and they all are opening away from you. When you get closer, you see three triangular parts...you smile as you think of how much it looks like the emblem on a Mercedes Benz! But you do not have time to dwell on that. Another companion floats nearby and shouts in passing, 'it's the tricuspid valve,' and adds with great excitement, 'there's not another one like it!' You are squeezed through this door and you find yourself in another chamber, even larger than the one you just left. It looks the same, but the walls appear to be stronger and thicker. It is still a wonderful blue all around you. The walls are blue, the atmosphere is blue, and you notice for the first time that your fellow travelers are also blue. You look at yourself, and discover that you are round, soft, and blue, too. This new chamber is the right ventricle of the heart of the person in whose body you are having this wonderful ride. "Before you have a chance to look around, you feel another squeeze coming. This one is much stronger and pushes you racing and rushing toward another double swinging door, which also swings outward away from you. This is the semilunar valve. As you rush toward this door, carried along, you hear a very loud noise behind you. "DUB!!!" It is the sound of the slamming tricuspid valve behind you. You are swept through this valve, and your companions are now all crowded together with you. No one is uncomfortable. It reminds you of those wonderful roller coaster rides when you were a child, the wind whipping your hair, and the great excitement. "You are now in a new tunnel, it is still light blue and it is beginning to narrow, to get smaller and smaller. You feel pressure and you have to move fast. Behind you, you hear the softer sound of the closing semilunar valve, "LUB!!!" As you are rushed along, you find yourself in the narrowest part of this new tunnel. You can hardly fit in by yourself, and you notice you and your companions are now in single file. You have moved from the pulmonary into a capillary. The walls are very thin (almost transparent) and the space is so narrow. As you continue on in single file, the tunnel curves and you are moving around a balloon-like chamber. You can see the walls of the chamber through the transparency of the tunnel. You see the balloon expanding and contracting, and if you listen carefully, you hear the sound of air moving in and out of the balloon, "Shush shush, shush shush." "The balloon chamber around which you are moving is one of the air sacs of the lung. You hear one of your companions whisper, "It's an alveolus." You see your companions in front of you are changing. You look again. They are slowly turning red. You are now moving right next to the transparent wall of the balloon-like chamber. You cannot be through it and you begin to see a substance separating from you. You realize you are changing color. The substance that made you blue moves through the wall into the air sacs. You are losing carbon dioxide. "You feel something strange is happening to you. You are gaining another substance and this substance is turning you red. You start to feel peppier, better somehow, more alive in a way you cannot describe. The new color suits you; you like it. You are becoming one with oxygen. "You do not have time to think; there is no stopping. You are still moving single file when you notice the tunnel is now getting larger. You do not feel so crowded. You start to hear the familiar "lub dub, lub dub" again. You see another opening, and you are carried into another chamber. It is very much like the first one you were in, but there is one wonderful difference. It is a beautiful deep red, like burgundy wine, like a wonderful deep red sun you saw reflecting in an ocean once. The noise is very loud. "Lub dub, lub dub, lub dub . . . " you feel fascinated and excited. You know you are safe here in the left atrium of the heart. You just moved into it from the pulmonary vein. You are right next to the chamber you were in first. You feel the walls squeezing you again. Squeezing you toward the only exit from this beautiful red chamber. "You continue on through this valve and find yourself in another chamber, the walls look very strong and thick and everything is tinted red, bright red. Before you know it, you feel the greatest squeeze yet . . . this is a BIG squeeze. You rush out through another swinging double door. You realize it is the semilunar valve, moving you from the left ventricle into the aorta, the largest tunnel so far. It is huge with branches leading out from it. And the noise, oh the noise! The loudest "DUB!" sound. It is the slamming of the bicuspid valve. "Some of your companions are separating from you, and behind you, you hear a softer "lub" sound which comes from the closing semilunar valve. You are taken into one of the branches going down, while others go through different branches. You smile at each other and say "See you around . . ." Somehow you know you will see each other again. You are being pushed towards something in a great rush. One of your companions shouts as you move downwards, "This guy must be jogging." The tunnel you are in is getting smaller and smaller and suddenly you find yourself in single file again. The tunnel is still red. As you move through this tiny tunnel with transparent walls, you see long slender columns lying next to each other on either side of this tunnel. These are the cells of the muscles. You now become aware that you have reached your destination. You feel the part of your substance, the beautiful red part, the oxygen is moving away from you through the transparent walls and into the muscle cells. And another substance is moving towards you, through the transparent wall, and when it joins you, you feel a familiar presence. You have given something away, and gotten something in return. As you look around, you notice your companions are changing in color again. They are turning blue. You look down at yourself and see that you are also blue again. "Suddenly you are pushed upwards, but you feel you are beginning to fade. The wizard's face grows more and more clear and you bid a fond "goodbye" to your companions as they return back upwards towards the heart to continue their journey forever." After the fantasy and a brief discussion, show a film on blood circulation. (There are many excellent films available.) Have the students write a short essay on the guided fantasy and the film. Encourage them to use metaphors to describe how the circulation of the blood works.

Assessment: Quality of the essays in terms of understanding the concept.

Assessment, Phase Two, Seeing the Big Picture:

4. Inform: Receiving Facts & Knowledge

Objective: To teach the concepts related to blood circulation. To give the students the opportunity to practice their note taking skills.

Activity: Teacher lectures on the following topics: circulation, the anatomy of the heart, pulmonary circulation, body circulation, coronary circulation, blood pressure, arteries, veins, heart attacks, and how materials are exchanged in the capillaries. Readings are assigned from the text.

Assessment: Objective quiz.

Assessment, Phase Three, Success with Acquiring Knowledge:

5. Practice: Developing Skills

Objective: To provide an opportunity for students to reinforce what they have learned through additional materials.

Activity: Workbook pages, questions at the end of text chapters.

Assessment: Quality of their work and depth of understanding.

Assessment, Phase Four, Success with Acquiring Skills:

6. Extend: Extending Learning to the Outside World

Objective: To give the students the opportunity to experience blood circulation in their own bodies and in other living things.

Activity: Have the students observe the blood circulation in the tail fin of a goldfish. This activity includes: wrapping a goldfish in wet tissue to keep it alive, placing the fish in a petri dish, spreading the tail fin on a glass slide and placing a coverslip over it, focusing a microscope (high power) on the tail fin, and observing the single-file movement of blood cells through the capillaries in the tail fin. Next, have the students measure their own blood pressures and pulses at rest and after a vigorous activity. Have them also measure the same in members of their immediate families. Tell them to log the results, making comparisons and contrasts.

Assessment: Quality of students' work.

7. Refine: Refining the Extension

Objective: To give the students the opportunity to organize a learning project which will further enrich their knowledge of blood circulation, and related concepts.

Activity: Students choose a project from a list prepared by the teacher. They will be required to do research on the chosen topic. Topics: artificial hearts; an essay with drawings, including the story of Barney Clark; the effects of nutrition and exercise on the health of the heart; a written report with appropriate charts; heart diseases and their causes, a written report; dangers to the heart and circulation in some teenage lifestyles, a newspaper article to be published in the school paper; the ten commandments for preventing heart attacks, to be published in the school paper; attending a CPR class and showing their classmates what they have learned; a written report on how to prevent high blood pressure; setting up a free blood pressure-taking booth after they have been instructed by a representative of the American Heart Association, in order to draw attention to this disease. Arrangements for this would have to be coordinated by the teacher.

Assessment: Quality of their work.

8. Perform: Creative Manifestation of Material Learned

Objective: To share what they have learned and experienced with their classmates.

Activity: Students present and explain their projects.

Assessment: Quality of presentation and depth of project.

Assessment, Phase Five,Performance, Creative Use of Material Learned: