Activity Overview. P.L.E.P: Parts of Blood. Cast Your Net: Adventures With Blood. Activity 1A. Activity Objectives: Activity Description:

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1 P.L.E.P: Parts of Blood Activity 1A Activity Objectives: Students will be able to: Work in a collaborative group to complete a given task Examine the different parts of blood Identify the parts of blood and construct a model of human blood Present their models to the class Activity Description: By performing this activity, students will determine the various components of blood and their functions. Students will construct simulated blood and examine its physical characteristics including density. Activity Background: Blood has been called our most precious commodity. Without this life sustaining substance, oxygen would not be circulated throughout the body, waste products could not be removed, and our infection fighting abilities would be lost. While the importance of blood has been known for centuries, it was not until 1658, when Jan Swammerdam first discovered red blood cells, that its composition was finally revealed. Blood is comprised of four main parts which include Plasma, Leukocytes (white blood cells), Erythrocytes (red blood cells), and Platelets (thrombocytes). Plasma is a pale yellowish colored liquid that carries blood cells, glucose, hormones, nutrients, enzymes, and waste products. Plasma is comprised of approximately 90% water. It accounts for a total of 55% of blood s total composition. Leukocytes are also known as white blood cells, and they make up 1% of blood s composition. These cells are responsible for fighting infection in the body. There are three types of leukocytes and each have a distinct function. These types are lymphocytes, granulocytes, and monocytes. Lymphocytes primarily aid the immune system. There are two different kinds of lymphocytes which are T cells and B lymphocytes. T cells direct the immune system to fend off infection. B lymphocytes produce antibodies. Activity Overview 1

2 Granulocytes carry digestive enzymes. The three types are neutrophils, eosinophils, and basophils. Neutrophils are responsible for killing bacteria. Eosinophils destroy various parasites and are involved in allergic responses. Basophils are capable of digesting micro-organisms. These cells are responsible for allergy symptoms. Monocytes are the largest of the various white blood cells. These cells can transform into macrophages, which kill bacteria and are capable of digesting damaged cells. Erythrocytes are also known as red blood cells; they are flat, disc-shaped cells that comprise 45% of blood s composition. These cells derive their red color from hemoglobin, an iron-containing protein that allows the cells to transport oxygen from the lungs to all parts of the body. The proportion of blood consisting of packed red blood cells is called hematocrit, which is written as a percentage by volume. For example, a hematocrit of 50 % means that there are 50 ml of red blood cells in 100 ml of blood. Platelets (thrombocytes), play a significant role in blood clotting. These cell fragments have a sticky surface which allows them to bind together with fibrin molecules to form a clot. Activity Materials: (per group) Simulated Blood Samples made as directed below from: 1% milk Vegetable oil Red food coloring Blue Food Coloring 20 ml Sample A Simulated Blood 20 ml Sample B Simulated Blood 20 ml Sample C Simulated Blood 3 Test tubes 3 Test tube stoppers 1 Test tube rack 1 Plastic soda bottle 2 m Strong String 1 Pair Scissors Safety Goggles for each student 1 Copy Student Information Page 1 Copy Student Data Page (per student) Activity Overview Continued 2

3 Teachers will need to make the following blood samples: For a class of 24 students (6 groups of 4), you will need 150mL of each blood sample. Each group will need 20 ml of each sample. Sample A (Normal Blood): Mix 67.5 ml of 1% milk with 82.5 ml of oil. Add several drops of red food coloring and one drop of blue food coloring to simulate blood. Sample B (Low Hematocrit Blood [anemia]): Mix 45 ml of 1% milk with 105 ml of oil. Add red and blue food coloring. Sample C (Elevated Hematocrit Blood [polycythemia vera]): Mix 105 ml of 1% milk with 45 ml of oil. Add red and blue food coloring. Normal Hematocrit (%) Male Female ** Be sure to shake or stir the simulated blood well before allowing the students to remove their samples. As shown in Figure 1, teachers will also need to make one student centrifuge per group. These can be reused for all classes. Hole Hematocrit Values Low Hematocrit (%) Male Figure 1 Making A Centrifuge Take one plastic soda bottle (16 ounces) and make a hole on each side of the bottom of the bottle. Thread a 2 meter length of strong string through the holes and tie a knot in the string. Students will put the stoppered test tube containing their blood sample into the bottle by removing the cap. Students will replace the cap and use the string to swing the bottle over their heads for one minute. They will then carefully remove the test tube from the centrifuge and place in a test tube holder and allow it to settle overnight. The centrifugal force of the centrifuge will start the process of settling the blood into layers. Students should be able to see a thin layer of plasma in their test tubes after using the centrifuge. Female <42 <35 String High Hematocrit (%) Male Female >54 >46 String-2 meter length Activity Overview Continued 3

4 Activity Management Suggestions: Modifications: For students needing more assistance: Group these students with peers who can assist them during the activity. Check often for understanding. For highly able students: Allow these students to do research on the parts of blood and their functions. Students may also be grouped with other students to provide peer assistance. Extensions: Students can research disorders involving the blood cells and platelets. Activity References Used: Anemia Website Medline Plus website: National Heart Lung and Blood Institute Website Sklar, A.H. (1998). Effects of normal as compared with low hematocrit values in patients with cardiac disease undergoing hemodialysis and receiving epoetin. The New England Journal of Medicine, 339, Activity Overview Continued 4

5 Activity Administrivia : Intended Grade Level: 6 10 Key Concepts: Blood, components of blood, red blood cells, erythrocytes, white blood cells, leukocytes, platelets, thrombocytes, granulocytes, lymphocytes, T cells, B lymphocytes, monocytes, macrophages, neutrophils, eosinophils, basophils, hemoglobin Process Skills Utilized in Lesson: Constructing, analyzing, simulate, differentiating, describe Previous Learning Assumed: Reading and following directions, circulatory system Relevant TEKS Science Grade 6: (3) Scientific processes. The student uses critical thinking and scientific problem solving to make informed decisions. The student is expected to: (C) represent the natural world using models and identify their limitations; (10) (B) determine that all organisms are composed of cells that carry on functions to sustain life; and(c) identify how structure complements function at different levels of organization including organs, organ systems, organisms, and populations. Grade 7: (3) Scientific processes. The student uses critical thinking and scientific problem solving to make informed decisions. The student is expected to: (C) represent the natural world using models and identify their limitations; (9) Science concepts. The student knows the relationship between structure and function in living systems. The student is expected to: (A) identify the systems of the human organism and describe their functions; Grade 8: 3) Scientific processes. The student uses critical thinking and scientific problem solving to make informed decisions. The student is expected to: (C) represent the natural world using models and identify their limitations; (4) Science concepts. The student knows that cells are the basic structures of all living things and have specialized parts that perform specific functions, and that viruses are different from cells and have different properties and functions. The student is expected to: (B) investigate and identify cellular processes including homeostasis, permeability, energy production, transportation of molecules, disposal of wastes, function of cellular parts, and synthesis of new molecules (5) Science concepts. The student knows how an organism grows and how specialized cells, tissues, and organs develop. The student is expected to: (A) compare cells from different parts of plants and animals including roots, stems, leaves, epithelia, muscles, and bones to show specialization of structure and function; Math Grade 6 (6.3) Patterns, relationships, and algebraic thinking. The student solves problems involving direct proportional relationships. The student is expected to: (A) use ratios to describe proportional situations; (B) represent ratios and percents with concrete models, fractions, and decimals Grade7 (7.3) Patterns, relationships, and algebraic thinking. The student solves problems involving direct proportional relationships. The student is expected to: (A) estimate and find solutions to application problems involving percent; Grade 8 (8.3) Patterns, relationships, and algebraic thinking. The student identifies proportional or nonproportional linear relationships in problem situations and solves problems. The student is expected to: (B) estimate and find solutions to application problems involving percents and other proportional relationships such as similarity and rates. Administrivia 5

6 P.L.E.P.: Parts of Blood Student Information Page 1A Activity Introduction: We ve all seen blood when we get a cut or scrape; did you ever wonder what it s made of? What does P.L.E.P. have to do with blood? In this activity, you ll find out! Activity Background: Blood has been called our most precious commodity. Without this life sustaining substance, oxygen would not be circulated throughout the body, waste products could not be removed, and our infection fighting abilities would be lost. While the importance of blood has been known for centuries, it was not until 1658, when Jan Swammerdam first discovered red blood cells, that its composition was finally revealed. Blood is comprised of four main parts which include Plasma, Leukocytes (white blood cells), Erythrocytes (red blood cells), and Platelets (thrombocytes). Plasma is a pale yellowish colored liquid that carries blood cells, glucose, hormones, nutrients, enzymes, and waste products. Plasma is comprised of approximately 90% water. It accounts for a total of 55% of blood s total composition. Leukocytes are also known as white blood cells, and they make up 1% of blood s composition. These cells are responsible for fighting infection in the body. There are three types of leukocytes and each have a distinct function. These types are lymphocytes, granulocytes, and monocytes. Lymphocytes primarily aid the immune system. There are two different kinds of lymphocytes which are T cells and B lymphocytes. T cells direct the immune system to fend off infection. B lymphocytes produce antibodies. Granulocytes carry digestive enzymes. The three types are neutrophils, eosinophils, and basophils. Neutrophils are responsible for killing bacteria. Eosinophils destroy various parasites and are involved in allergic responses. Basophils are capable of digesting micro organisms. These cells are responsible for allergy symptoms. 6

7 Monocytes are the largest of the various white blood cells. These cells can transform into macrophages, which kill bacteria and are capable of digesting damaged cells. Erythrocytes are also known as red blood cells; they are flat, discshaped cells that comprise 45% of blood s composition. These cells derive their red color from hemoglobin, an iron-containing protein that allows the cells to transport oxygen from the lungs to all parts of the body. The proportion of blood consisting of packed red blood cells is called hematocrit, which is written as a percentage by volume. For example, a hematocrit of 50 % means that there are 50 ml of red blood cells in 100 ml of blood. Platelets (thrombocytes), play a significant role in blood clotting. These cell fragments have a sticky surface which allows them to bind together with fibrin molecules to form a clot. Activity Materials: (per group) 20 ml of simulated blood from sample A, B, and C 3 test tubes with stoppers 1 student centrifuge 1 Test tube rack 1 Copy Student Information Page 1 Copy Student Data Page (per student). Activity Instructions: Day 1 1. Gather your materials. Label the 3 test tubes Patient A, Patient B, and Patient C. 2. Put 20 ml of simulated blood from the Patient A container into the test tube labeled Patient A and place a stopper in the test tube. 3. Record your observations for Day 1 on your Student Data Page in Table 1. Use a ruler to measure the height of the blood in the test tube 9n millimeters. Record your data in Table Place the test tube in the centrifuge so that the stopper goes in first and close the lid. 5. Take the centrifuge outside and swing it around your head for 1 minute. This action is similar to what happens in a laboratory centrifuge. This action causes the blood to separate into layers. The heaviest layer containing erythrocytes will be at the bottom of the test tube. The middle layer will be made up of leucocytes and platelets and the top layer will contain the plasma. 7

8 6. Bring the centrifuge back inside and remove the test tube being careful not to disturb the blood. 7. Place the test tube into the test tube rack and let sit overnight. This will allow the blood to finish settling into layers. 8. Repeat steps 2-7 for the blood from Patients B and C. Day 2 1. Record your observations for Day 2 for each test tube in Table 1 on your Student Data Page. 2. Use a ruler to measure (in millimeters) the layers in each tube. Record these measurements in Table 1 on your Student Data Page. 3. Calculate the percentage of Red Blood Cells (erythrocytes) in each test tube; divide the measurement for the bottom layer of blood by the total height of the blood in the tube and multiply by 100. Record your answer. 4. Calculate the percentage of plasma in each test tube by dividing the measurement for the top layer of blood by the total height of the blood in the tube and multiply by Determine the blood health of the patients using the Hematocrit Values table below.. HEMATOCRIT VALUES Normal Hematocrit (%) Low Hematocrit (%) High Hematocrit (%) Male Female Male <42 Female <35 Male >54 6. Research the types of conditions associated with high and low percentages of erythrocytes. Female >46 8

9 P.L.E.P.: Parts of Blood Student Data Page 1A 1. Record your data. Table 1 Observations on Parts of Blood Day Test tube Height of blood in tube (mm) Height of bottom layer (mm) Height of top layer (mm) % Red Blood Cells % Plasma Observations 1 A B C 2 A B C Calculating Box 9

10 2. Make a graph of your results be sure to include a title, axes labels and a legend on your graph. Student Name (Axis label) (Axis label) 10

11 Processing Out: 1. List the parts of human blood. 2. What does the title P.L.E.P. stand for? 3. What is the function of plasma? 4. What is the function of white blood cells? 5. What is the function of red blood cells? Blood Cell Blood Cell 11

12 6. What is the function of the platelets? 7. If you have a lower number of red blood cells, what might that do to your body? 8. If you have low numbers of white blood cells, what symptoms might you expect? 9. How might you know if you do not have enough platelets? 10. How does the blood help other parts of the body? 12