BODY 41 9 Heartily Fit l a b o r at o r y So far in this unit, you have looked at many of your body’s systems and taken a closer look at the digestive and nervous systems. You have also begun to learn how scientists study people. In the upcoming activities, you will continue to study people by looking at some other body systems and how they function. 143144 One important body function is the ability to walk, run, and do other physical tasks. How does physical activity affect your body? Is everyone’s body affected in the same way? How do scientists measure these effects? In this activity, you will collect data on yourself. You will measure your pulse (the rate of your heartbeat) and your respiratory rate before and after you exercise. GUIDING QUESTION How do your body systems respond to exercise? MATERIALS For the class access to a wall clock or watch that displays seconds For each pair of students 1 calculator For each student 1 Student Sheet 9.1, “Heart and Respiratory Rate Data” 143 NGCCSM1 144 NGLS1A3
ACTIVITY 9 HEARTILY FIT 42 BODY SAFETY Do not participate in this activity if you have any condition that prevents you from exercising. If you begin to feel dizzy or short of breath during exercise, stop exercising immediately and tell your teacher. PROCEDURE Part A: Make Predictions 1. In your science notebook, respond to the following questions: a. When you are at rest, how many times do you think: • Your heart beats (as measured by your pulse) in 1 minute (min)? • You breathe (as measured by inhale/exhale cycles) in 1 min? b. After you have done some moderate exercise, how many times do you think: • Your heart beats (as measured by your pulse) in 1 min? • You breathe (as measured by inhale/exhale cycles) in 1 min? Part B: Collect Baseline Heart and Respiratory Rate Data145146147 2. Work with your partner. Decide which of you will go first to complete Steps 3–7. 3. Prepare to measure your heart rate by sitting comfortably. 4. Use the first two fingers of one hand to locate your pulse at the base of your wrist or on the side of your neck. 5. Measure your pulse for 30 seconds (s). Have your partner keep track of the time. 6. Record your data for Trial 1 in the Heart Rate section on Student Sheet 9.1, “Heart and Respiratory Rate Data.” 7. Repeat Step 4 two more times, and record your data for Trials 2 and 3. 145 SELTRS1 146 SELTLW1 147 ELRS683 The two easiest places to feel your pulse: • The artery at the base of your wrist (of either hand). • The artery at the side of your neck.
HEARTILY FIT ACTIVITY 9 BODY 43 8. Switch roles with your partner, and repeat Steps 3–7. 9. Calculate your pulse for 60 s by multiplying each 30-second pulse by 2. 10. Calculate your average resting pulse per minute. Do this by adding all the numbers in the column titled “60-Second Pulse.” Then divide your total by 3. Record your average resting pulse per minute on Student Sheet 9.1. 11. Measure your respiratory rate by breathing normally and counting inhales for 30 s. Have your partner keep track of the time. 12. Record your data for Trial 1 in the Respiratory Rate Section on Student Sheet 9.1. 13. Repeat Step 11 two more times, and record your data for Trials 2 and 3. 14. Switch roles with your partner, and repeat Steps 11–13. 15. Calculate your respiratory rate for 60 s by multiplying each 30-second rate by 2. 16. Your teacher will tell you how to share your responses with the class. Look at the range of the class data. The range is the difference between the lowest and highest data points. Use the range of the class data to answer the following questions in your science notebook: • What is the range of the class results? • Did your prediction fall within that range? • If so, where did it fall? 17. Use the class data to create two scatterplots, one for heart rate and one for respiratory rate.148 Part C: Effects of Exercise on Heart and Respiratory Rates 18. Your teacher will assign you to collect data on either your heart rate or your respiratory rate. Everyone will do Step 19. If you are collecting data on your heart rate, you will then do Step 20. If you are collecting data on your respiratory rate, you will skip to Step 21. 148 MASP6B4
ACTIVITY 9 HEARTILY FIT 44 BODY 19. As discussed in class, exercise for 5 min. After 5 min, stop exercising and sit down. Hint: If you can have a normal conversation while exercising, you are not exercising hard enough. If you cannot talk at all, you are exercising too hard. 20. To collect heart rate data: Immediately after sitting down, begin taking your pulse. a. Record your 30-second pulse every 60 s for the next 3 min on Student Sheet 9.1. b. Calculate your 60-second pulse for each time period by multiplying each 30-second pulse by 2. 21. To collect respiratory rate data: Immediately after sitting down, begin counting your breaths for 30 s. a. Record your 30-second respiratory rate every 60 s for the next 3 min on Student Sheet 9.1. b. Calculate your 60-second respiratory rate for each time period by multiplying each 30-second rate by 2. 22. Did you notice any other changes in your body systems since you began exercising? If yes, record your observations on Student Sheet 9.1. Did you know that you can have a career helping people recover from injuries or stay fit? This type of work is known as physical therapy and occupational therapy.
HEARTILY FIT ACTIVITY 9 BODY 45 ANALYSIS 1. Use the class data to answer these questions: 149150 a. What happened to students’ heart rate during exercise? b. What happened to students’ respiratory rate during exercise? 2. What do you think caused the effects you just described? Explain in terms of what you think happens inside the body and how things change during exercise. 3. What evidence do you have that your circulatory and respiratory systems work together? 151152153154 4. What other body systems are affected by exercise? Explain your thinking. 5. If you improved your level of physical fitness: a. Would your resting pulse increase or decrease? Explain. b. Would your respiratory rate increase or decrease? Explain. EXTENSION Brainstorm exercises that you can easily do and like to do. Develop a plan to exercise regularly for the next month. You should exercise at least three times a week for at least 20 min each time. Keep a record or log of the dates and times that you exercise. After exercising for a month, repeat Part B of the Procedure. What effect does regular exercise have on your resting pulse and respiratory rate? 149 NGSPUM1 150 NGSPAD3 151 SEASAD1 152 NGLS1A3 153 NGCCSM1 154 NGLS1A3
BODY 47 10 Gas Exchange l a b o r at o r y I n th e “He ar ti ly Fit” activity, you observed the effects of exercise on your circulatory and respiratory systems. With every breath you take, you inhale oxygen and exhale carbon dioxide. The cells in your body need oxygen so they can break down food and release energy. Without oxygen, your cells cannot get the energy they need to live. When your cells break down food, they produce wastes. One of these wastes is carbon dioxide. The function of the respiratory system is to exchange gases, removing carbon dioxide wastes and taking in oxygen.155156 Indicators are chemicals that change their appearance in different types of solutions. You will work with the indicator bromothymol blue, also known as BTB. BTB can be either blue or yellow. When added to a solution containing carbon dioxide, BTB is yellow. GUIDING QUESTION How much carbon dioxide is in your exhaled breath before and after you exercise? 155 NGLS1A3 156 NGPS3D2 Both solutions contain the indicator BTB. Which cup has a solution containing carbon dioxide?
ACTIVITY 10 GAS EXCHANGE 48 BODY MATERIALS For each group of four students 1 dropper bottle of bromothymol blue (BTB) indicator 5 plastic cups supply of water For each pair students 1 dropper bottle of 0.05 M sodium hydroxide 1 SEPUP tray 1 dropper 1 30-mL graduated cup For each student 2 1-gallon plastic bags 2 straws 1 stir stick 1 pair of chemical splash goggles access to a wall clock or watch that displays seconds 1 Student Sheet 10.1, “Anticipation Guide: Gas Exchange” SAFETY In this activity, you will blow through a straw into chemicals. Do not inhale through the straw! Breathe in through your nose and exhale through your mouth. If you accidentally swallow liquid, rinse your mouth thoroughly and drink plenty of water. Be sure to tell your teacher. Wear chemical splash goggles while working with chemicals. Do not touch chemicals or bring them into contact with your nose or mouth. Wash your hands thoroughly after completing the activity. PROCEDURE Complete the “Before” column on Student Sheet 10.1, “Anticipation Guide: Gas Exchange,” to prepare you for learning about the respiratory system. 157 Part A: Test for Carbon Dioxide 158 1. Work with your partner to add 5 mL of water to each of the five large cups (A–E) of your SEPUP tray. Use the 30-mL graduated cup to measure the water.159 2. Add 2 drops of BTB to each cup, and stir. 157 SELTAG1 158 NGSPP13 159 ELRS683
GAS EXCHANGE ACTIVITY 10 BODY 49 3. Create a data table to record the initial and final colors of the solutions in each cup. Record the initial colors now. Cup A will provide a control. 4. Use your dropper to bubble air into Cup B. Place the dropper into the solution, and press the air out of the bulb. Before releasing the bulb, remove the tip from the solution. This will prevent uptake of solution into the dropper. (If you accidentally get solution into the dropper, simply squirt it back into Cup B.) Repeat this for 15 s. 5. Record the final color of the solution in Cup B in your data table. 6. Add 3 drops of 0.05 M sodium hydroxide to Cup C. Record the final color in your data table. 7. Have one partner unwrap a straw and place one end in Cup D. That partner should take a deep breath and then gently blow through the straw for 15 s. (Do not inhale through the straw!) Record the final color of the solution in Cup D in your data table. 8. Have the other partner blow through a clean straw into Cup E for 15 s. (Do not inhale through the straw!) Record the final color in your data table. 9. Add 3 drops of sodium hydroxide to Cups D and E. In your science notebook, record any changes that you observe. 10. Work with your partner to complete Analysis items 1 and 2. Part B: Measure Carbon Dioxide in Exhaled Breath Before and After Exercise160161 11. Work with another pair of students to set up a control.162 a. Use the 30-mL graduated cup to measure 10 mL of water. b. Add 5 drops of BTB to the graduated cup, and stir. c. Pour the BTB solution into a large plastic cup. This solution will be the control for every member of your group. 160 NGSPPI2 161 NGSPPI3 162 ELRS683
ACTIVITY 10 GAS EXCHANGE 50 BODY 12. Have each person in your group set up their own bag of BTB solution. a. Use the 30-mL graduated cup to measure 10 mL of water. b. Add 5 drops of BTB to the graduated cup, and stir. c. Pour the BTB solution into your own plastic bag. 13. Remove the air from your plastic bag by slowly flattening it. Be careful not to spill any of the BTB solution out of the bag. While keeping the air out of the bag, place a straw in the mouth of the bag. Make an airtight seal by holding the mouth of the bag tightly around the straw. 14. Be sure that you are sitting down. Fill the bag with air from your lungs by blowing through the straw until the bag is fully inflated. When you finish blowing, pull out the straw while squeezing the bag tightly shut so that no air escapes. 15. Keep holding the bag closed, and shake it vigorously 25 times. 16. Pour the BTB solution from the bag into a clean, empty plastic cup. 17. How much carbon dioxide is in your exhaled breath? You can find out by counting how many drops of sodium hydroxide are needed to make your BTB solution the same color as the control. a. Add 1 drop of sodium hydroxide to your plastic cup. b. Gently stir the solution, and wait at least 10 s. c. Record in your science notebook that you added 1 drop. d. Compare the color of your solution to the control. Is it the same color as the control for at least 30 s? • If your answer is no, repeat Steps 17a–d. Be sure to keep track of the total number of drops! • If your answer is yes, go on to Step 18. 18. In your science notebook, record the total number of drops it took to change your solution back to the same color as the control. Then record your total on the class data table. 19. Repeat Steps 12 and 13 to prepare your bag of BTB for the remaining steps.
GAS EXCHANGE ACTIVITY 10 BODY 51 20. As discussed in class, exercise for 5 minutes. After 5 minutes, stop exercising and sit down. Hint: If you can have a normal conversation while exercising, you are not exercising hard enough. If you cannot talk at all, you are exercising too hard. 21. Repeat Steps 14–18. 22. Draw a bar graph with the class results before and after exercising. Remember to title your graph and label the axes. EXTENSION Asthma is a common medical condition that affects many people’s breathing. With your partner or group, discuss what questions you have about asthma and how it affects the respiratory system. To research the answers to your questions, visit the SEPUP Third Edition Body Systems page of the SEPUP website at www.sepuplhs. org/middle/third-edition, and go the resources on asthma. ANALYSIS 1. What was the purpose of the solution in Cup A? 2. Review your results.163164 a. Which of the solutions in Part A contained carbon dioxide? Support your answer with evidence from your experimental results. b. What does this tell you about the exhaled breath of human beings? c. Look at the table below. Compare the composition of air you breathe in to that of air you breathe out. Describe the differences. Composition of Breath COMPONENTS OF EARTH’S ATMOSPHERE COMPOSITION OF AIR BREATHED IN (%) COMPOSITION OF AIR BREATHED OUT (%) Nitrogen 78 75 Oxygen 21 16 Argon 0.93 0.93 Carbon dioxide 0.036 4.0 Water vapor 0.4 4.0 163 NGPS3D2 164 NGSPAD3
ACTIVITY 10 GAS EXCHANGE 52 BODY 3. Based on what you learned in this activity, describe the function of the respiratory system.165 4. Look at the diagram of the human respiratory system. Considering the function of the respiratory system that you described for Analysis item 3, why do you think the inside of the lung is structured the way it is?166 5. Complete Student Sheet 10.1. Be sure to explain how the activity provided evidence for your initial ideas or caused you to change your thinking. 6. Revisit the issue: Many respiratory diseases limit a person’s ability to exchange oxygen. One of these diseases is pneumonia, which causes the lungs to fill up with fluid. Another is pleurisy, which is an inflammation of the lining of the lung, making it painful to inhale and exhale. If you had one of these diseases, how do you think it would affect your body’s function? 165 NGCCSM1 166 NGLS1A3 lungs trachea (windpipe) air exhaled breath with carbon dioxide waste nose mouth blood leaving lungs (carries oxygen to body) alveoli (air sacs) a thin layer of tissue forms the walls of the air sacs blood coming to lungs from body (carries carbon dioxide waste) Seventeenth Street Studios Science and Life Issues Fig. SE1-17-01 6892-01 C M Y K Human Respiratory System
BODY 53 11 Interacting Systems r e a d i n g So far in this unit, you have investigated the functions of three body systems that work together to provide the cells of your body with nutrients and oxygen. Without a steady supply of nutrients and oxygen, cells would not be able to get energy, causing them to rapidly die. These functions depend on your digestive system, respiratory system, and circulatory system. Your nervous system also plays a role in coordinating the activities of these systems. In this Reading, you will learn more about how the organs, tissues, and cells of these systems work together to keep you alive. GUIDING QUESTION How do systems in your body work together to keep you healthy? MATERIALS For each student 1 Student Sheet 11.1, “Heart Diagram” 1 red/blue combo colored pencil Digestive System stomach tissues of stomach lining stomach cells System Organ Tissue Cell lungs lung tissue lung cell System Organ System TissueOrgan CellTissue Cell heart heart tissue heart muscle cells Digestive System Respiratory System Circulatory System
ACTIVITY 11 INTERACTING SYSTEMS 54 BODY PROCEDURE 1. Read the text below. 2. Follow your teacher’s instructions for how to use the Stop to Think questions.167 168 READING Circulatory System Structure and Function Your circulatory system, also called your cardiovascular system, includes your heart, blood vessels, and blood. The diagram below shows the structures of this system. To understand the circulatory system, it is important to think about the structures and functions of the whole system, as well as the organs and cells in that system. Your blood is a tissue that includes both cells and liquid material. Oxygen and most carbon dioxide wastes are transported by red blood cells. Nutrients are dissolved in the liquid part of the blood. Your heart is made up of four chambers that work as two pumps. The right side of your heart acts as a pump that pumps oxygen-poor blood to your lungs. The left side of your heart acts as another pump that pumps oxygen-rich blood to all parts of your body. The walls of your heart are made of thick layers of muscle tissue that contracts and relaxes continually throughout your life. Your nervous system sends signals that control how fast your heart contracts. 167 SELTST1 168 ELRS682 System Organ Tissue Cell heart heart tissue heart muscle cells Levels of Organization in the Circulatory System Note that these drawings are not to scale.
INTERACTING SYSTEMS ACTIVITY 11 BODY 55 Look at the heart diagram above. It shows the heart of a person facing toward you. That is why the right side of the diagram is labeled “left” and the left side is labeled “right.” Blood always enters your heart through the two chambers known as atria—the plural for atrium. Blood is pumped out of your heart through two other chambers, the ventricles. Valves in your heart help keep blood moving in one direction. 169 STOP TO THINK 1 On Student Sheet 11.1, “Heart Diagram,” label the left and right sides of the heart. Use your finger to trace the flow of blood through the right side of the heart. Notice where the blood is coming from and where it is going. Repeat this process for the left side of the heart. The walls of your heart are mostly muscle tissue, composed of muscle cells. These cells are specialized to contract and relax over and over, without ever resting, for your entire life. The heart muscle cells need a steady supply of oxygen to provide energy for the cells to contract. When the heart muscle doesn’t get enough oxygen, a heart attack can result. 169 SELTST1 Seventeenth Street Studios Science and Life Issues Fig. SE1-23-02 6892-01 C M Y K pulmonary artery pulmonary artery pulmonary veins vein from body vein from head arteries to head and arms aorta right ventricle left ventricle right atrium left atrium Heart Diagram
ACTIVITY 11 INTERACTING SYSTEMS 56 BODY Blood travels through your body in a network of tubes of various sizes. These tubes are known as blood vessels. At various points in the network, blood vessels are called arteries, veins, or capillaries. Remember finding your pulse in the “Heartily Fit” activity? You can feel your pulse as your heart pumps blood through your arteries. Arteries carry blood away from your heart. Most arteries carry oxygen-rich blood to the organs. Veins carry blood back to your heart. Most veins carry blood with lower levels of oxygen and higher levels of carbon dioxide (picked up from the organs).170 Blood leaving the left side of your heart flows into arteries that carry oxygen to all parts of your body. Arteries become smaller and smaller until they become capillaries, which are found throughout all tissues and organs of the body. Capillaries are blood vessels with walls so thin that oxygen, nutrients, and wastes can pass back and forth from the blood to the surrounding tissues, such as muscle. Each capillary is very small, and there are many of them. They provide lots of surface area for oxygen to move to the tissues and carbon dioxide wastes to move out of the tissues. STOP TO THINK 2 a. Which blood vessels carry blood away from the heart to the organs? b. Which blood vessels carry blood back to the heart from the organs? c. Which small blood vessels connect the vessels that carry blood away from the heart to the vessels that return blood to the heart? Respiratory System Structure and Function Many organisms, including all animals and plants, require oxygen to break down sugars and release carbon dioxide and energy. In humans and other mammals, the respiratory system is responsible for the intake of oxygen and release of carbon dioxide. This system includes the lungs and a series of passages that lead from the nose and mouth to the lungs. As an organism inhales, muscles cause the lungs to expand, and air moves into the expanded lung space. As the organism exhales, muscles in the lungs relax, and air is forced out. An organism changes its rate and depth of breath in response to carbon dioxide levels in the blood. If carbon dioxide levels in the blood 170 SELTST1
INTERACTING SYSTEMS ACTIVITY 11 BODY 57 are high, the organism will breathe faster or deeper. If carbon dioxide levels are low, the organism will breathe slower. In the “Gas Exchange” activity, you explored the release of carbon dioxide wastes by humans through their respiratory systems. The lungs are large sacs composed of many smaller sacs called alveoli, similar to a sponge filled with small spaces. The figure on the right shows the air spaces of the lungs and how they branch to the many tiny alveoli. The walls of the alveoli are a single layer of tissue. This tissue is composed of very thin pancake-shaped cells. The exchange of gases in the lungs takes place across these thin cells. lungs trachea (windpipe) air exhaled breath with carbon dioxide waste nose mouth blood leaving lungs (carries oxygen to body) alveoli (air sacs) a thin layer of tissue forms the walls of the air sacs blood coming to lungs from body (carries carbon dioxide waste) Seventeenth Street Studios Science and Life Issues Fig. SE1-17-01 6892-01 C M Y K Human Respiratory System This plastic mold shows the airways and air sacs in the lungs. Compare it with the diagram of the lungs above.
ACTIVITY 11 INTERACTING SYSTEMS 58 BODY The diagram above shows the respiratory system, the lungs, the tissue in the alveoli, and one of the flat cells from the alveoli. STOP TO THINK 3 How does oxygen get from the environment into the lungs and then to cells throughout the body? Systems Working Together The capillaries play a central role in the exchange of material between the blood cells and the cells in all other tissues of the body. Branching capillary networks come in close contact with other tissues. The capillaries have very thin walls made of just one layer of flattened cells. These thin walls allow substances, like oxygen and sugars, to move from the blood in the capillaries into the cells of the surrounding tissues and, like carbon dioxide and other wastes, to move from the tissues into the blood stream. In “Digestion: An Absorbing Tale,” you learned that nutrient exchange between the digestive system and the blood takes place in a network of capillaries that lies just below the lining of the small intestine. The diagram on the next page shows the capillaries in the small intestine. Gas exchange between the blood and the air in the lungs occurs in capillaries that surround the alveoli of the lungs. This is shown in the lungs lung tissue lung cell System Organ Tissue Cell Levels of Organization in the Respiratory System Note that these drawings are not to scale.
INTERACTING SYSTEMS ACTIVITY 11 BODY 59 diagram above. While the blood in arteries and capillaries that goes to most organs is rich in oxygen, the blood that goes to the lungs from the organs is low in oxygen and high in carbon dioxide. In the alveoli, these capillaries come into close contact with the lining of the lungs, allowing carbon dioxide to move across from the blood to the space in air of the alveoli and oxygen to move from the air in the alveoli into the capillaries.171 STOP TO THINK 4 How does the structure of the capillaries allow them to perform the function of gas, nutrient, and waste exchange? ANALYSIS 1. Gather Student Sheet 11.1, “Heart Diagram,” and your red/blue colored pencil. a. Use the red pencil to shade areas that contain blood carrying higher levels of oxygen (and lower levels of carbon dioxide). Use the blue pencil to shade areas that contain blood carrying higher levels of carbon dioxide (and lower levels of oxygen). b. Recall that arteries carry blood away from your heart and that most arteries carry blood with higher levels of oxygen. Look carefully at the pulmonary arteries on Student Sheet 11.1. Explain how these arteries are different from most arteries in your body. Hint: Think about the blood they are transporting. 171 SELTST1 Seventeenth Street Studios Science and Life Issues Fig. SE1-17-01 6892-01 C M Y K Capillaries, such as the ones shown in the villi of the small intestine (left) and alveoli of the lungs (right), carry nutrients, oxygen, waste, and other materials throughout your body.
ACTIVITY 11 INTERACTING SYSTEMS 60 BODY c. Recall that veins carry blood to your heart and that most carry blood with lower levels of oxygen. Look carefully at the pulmonary veins on Student Sheet 11.1. Explain how these veins are different from most veins in your body. Hint: Think about the blood they are transporting. 2. Look carefully at the diagrams of the human respiratory system. 172 a. What are some of the important structures in the respiratory system? b. Where are gases exchanged in the respiratory system? c. Describe the structures that make gas exchange between the lungs and blood possible. 3. Explain how structures in the circulatory system, including organs, tissues, and cells, each contribute to the circulatory system’s function.173174 4. How and where do the digestive and circulatory systems interact? 175 5. Revisit the issue: Many medicines are in the form of pills taken orally. What do you think has to happen to a medicine, such as a headache medicine, in order for it to relieve headache pain? 176 EXTENSION To view an animation of the heart, visit the SEPUP Third Edition Body Systems page of the SEPUP website at www.sepuplhs.org/middle/ third-edition, and see the “Heart Contraction and Blood Flow” animation. 172 NGCCSF1, NGCCSM1 173 SEASEX1 174 NGLS1A3, NGSPCE6 175 NGCCSM1 176 NGSPNS1
BODY 61 12 The Circulation Game m o d e l i n g You have been learning about the structures and functions of several systems and subsystems in your body. In this activity, you will summarize some of what you have learned by developing a model of the path that your blood takes as it moves through your body. This model will help you better understand how the circulatory system and other body systems interact. GUIDING QUESTION How do oxygen, nutrients, and wastes move into, within, and out of your body? MATERIALS For each student 1 Role Card 1 elastic string with metal tabs at each end for the Role Card PROCEDURE Part A: Blood Flow177 1. Look at the diagram on the next page of blood flow. This is a simplified map of how blood travels around your body. Use your finger to trace one of the possible paths of blood flow. Begin on the left side of the heart (on your right), and stop once you reach the left side of the heart again. Be sure to go in the direction of the arrows. 2. In your science notebook, record which organs and structures you passed through in your path. 3. Repeat Steps 1 and 2 by tracing a different path of blood through the human body. 177 NGCCSF1 LabAids SEPUP IAPS Body Systems 3e Figure: BodySys3e SB 12_trailing MyriadPro Reg 9.5/11 Human Circulatory System
ACTIVITY 12 THE CIRCULATION GAME 62 BODY 4. Discuss the following questions with your group members, and be prepared to share your ideas with the class: • Did everyone trace the same paths? If not, compare the organs (and structures) along the different paths. • Which organs does the blood have to pass through each time it goes around the human body? • Why do you think blood always has to pass through these organs? 5. Use the class discussion and your knowledge of the human body to complete the table below. Functions of Certain Organs/Structures Function Organ or Structure System Pumps blood Brings oxygen into the body Releases carbon dioxide from the body Absorbs nutrients Signals the heart to contract faster or slower Carries gases and nutrients around the body brain stomach and intestines liver kidneys leg muscles lungs heart Diagram of Blood Flow
THE CIRCULATION GAME ACTIVITY 12 BODY 63 Part B: Modeling Circulation178 6. Your teacher will give you a Role Card. Read it carefully to see what your job will be. Be sure to note how many oxygen, nutrient, carbon dioxide, and waste cards you need to collect before beginning the game. 7. Collect all the Substance Cards that you need from your teacher. Keep the oxygen, nutrient, carbon dioxide, and waste cards in separate stacks so that exchanges can take place quickly. Attach your Role Card to your clothing. 8. Your teacher will assign one student playing the role of blood to walk through one path of the blood flow diagram. Watch where the blood cell goes and what happens at each organ. 9. Take your place on the diagram, and begin playing the Circulation Game. If you’re playing the role of blood, start walking along a circulation path. You may start anywhere on the blood flow diagram, but you must follow the direction of the arrows. 10. As a class, decide how you will incorporate the heart rate into your model and keep the model running smoothly. 11. As the blood flows through the body, carbon dioxide and waste products build up in the organs. The stomach and lungs start running out of food and oxygen. As a class, figure out how to adjust the model to take care of these problems.179 178 NGCCSM1 179 NGSPDM2 The Model You will model the way that your blood transports oxygen, nutrients, and carbon dioxide and other wastes. You will receive a Role Card that describes which part of the human body you will play: blood, brain, heart, lungs, stomach and intestines, liver, kidneys, or leg muscles. In this model, as blood flows through the human body, it will absorb oxygen and nutrients and carry them to other parts of the body. “Organs” will use the nutrients and oxygen and get rid of carbon dioxide and other wastes by giving them to the blood. Colored Substance Cards represent the four substances (oxygen, nutrients, carbon dioxide, and waste) that are being transported.
ACTIVITY 12 THE CIRCULATION GAME 64 BODY 12. If you have time, switch Role Cards and play the Circulation Game again. EXTENSION Discuss with your group or as a whole class how you would add the nervous system to your model. Conduct the model again, if you have time. ANALYSIS 1. Compare this circulation model to the actual human body. How well did the Circulation Game represent what really happens inside your body? 2. Do all parts of the human body use oxygen and nutrients? Explain your answer. 180181182 3. Look at the following diagram. a. Use your finger to trace the path between Point A and Point B, making sure to follow the direction of the arrows. List the organs in the order in which you passed through them. b. Imagine blood carrying only carbon dioxide and nutrients at Point A. Describe what happens to the blood as it flows from Point A to Point B. 180 NGSPCE6 181 NGSPCE6 182 ELWH682 stomach and intestines liver lungs heart A B
THE CIRCULATION GAME ACTIVITY 12 BODY 65 4. Revisit the issue: Your friend says, “Your muscles wouldn’t be able to do their job without your other body systems and the organs, tissues, and cells in those systems.” Do you agree or disagree with your friend’s claim? Develop an argument to support your position. Be sure that your argument includes convincing examples to support your claim.183184185186187 183 SEASAR1, SELTWF2, SEASAM1 184 NGPEL13 185 NGLS1A3 186 NGSPEA2 187 ELWH681
BODY 67 i n v e s t i g at i o n I magine that you suffer from severe headaches several times a month. These headaches are so painful that you can’t read, listen to music, or watch television. Regular headache medicines don’t work very well for you. One day, you complain to your doctor about your headaches. She tells you that the local medical school is conducting clinical trials of a new headache medicine. She asks you and your parent if you would like to volunteer to be a part of this trial. You and your parent talk about it and decide that you would like to try being part of the trial. Since medicine cannot be tested in the classroom, you will participate in a model of a clinical trial. In this model, differences in taste will equal differences in response to the medicine. Clinical trials usually involve several phases, and new medicines are tested on hundreds to thousands of people before they are approved for public use. In this model, you are using only the students in your class as participants, similar to how many people a new medicine might be tested on in the first phase of a clinical trial. The illustration on the next page, “Clinical Trial of a Headache Medicine,” explains the model. 188 GUIDING QUESTION How are medicines tested during a clinical trial? MATERIALS For each group of four students 1 sample cup of yellow lemon drink 1 sample cup of pink lemon drink For each student 1 small tasting cup 1 Student Sheet 13.1, “Analysis of Clinical Trial” 188 NGCCNS1 13 Testing Medicines: A Clinical Trial
ACTIVITY 13 TESTING MEDICINES: A CLINICAL TRIAL 68 BODY The taste of the pink lemon drink represents the medicine taken to treat your headache. The taste of the yellow lemon drink represents a headache. If the pink lemon drink tastes the same to you as the yellow drink, there is no change in your headache. If the pink lemon drink tastes better to you than the yellow drink, your headache is gone! If the pink lemon drink tastes worse to you than the yellow drink, your headache is gone, but you are experiencing side effects. Clinical Trial of a Headache Medicine
TESTING MEDICINES: A CLINICAL TRIAL ACTIVITY 13 BODY 69 SAFETY Never taste materials or eat or drink in science class unless specifically told to do so by your teacher. Be sure that your work area is clean and free of any materials not needed for this activity. If you are allergic to lemons or other citrus fruits, juice drinks, or sugar, or if you have any other health issue that limits what you can eat or drink, such as diabetes, tell your teacher and do not taste the drink samples in this activity. PROCEDURE189 1. Record your group number (found on the sample cups) in your science notebook; this represents the batch of medicine you received. 2. Fill your tasting cup halfway full of yellow lemon drink by carefully pouring from the sample cup into your tasting cup. 3. Taste the yellow lemon drink. Empty the cup. 4. Fill your tasting cup halfway full of pink lemon drink. 5. Taste the pink lemon drink. 6. Did the pink lemon drink taste the same, better, or worse than the yellow lemon drink? Record your response in a table like the one below. Results of Treatment Same as yellow lemon drink Better than yellow lemon drink Worse than yellow lemon drink My response (show with an X) My group’s response (show number of each) 7. Share your results with your group. Summarize your group’s results in the “My group’s response” row of your data table. 8. Have one person from your group report your group’s results to your teacher. 9. After a class discussion of the results, record the class’s results and create a bar graph of the class’s data on Student Sheet 13.1, “Analysis of Clinical Trial.” 189 ELRS683
ACTIVITY 13 TESTING MEDICINES: A CLINICAL TRIAL 70 BODY 10. Discuss the following with your group: Assume that the side effects of a headache medicine are mild, such as a slight stomachache. Do you think this medicine should or should not be sold to people suffering from a headache? Are there any trade-offs involved in your decision? If so, why did you make the decision you did?190 ANALYSIS 1. What body systems are a headache medicine likely to affect? Explain. 2. In this activity, what evidence do you have that the medicine does or does not have the desired effect of improving headaches?191 192 193 3. Who was the control group in this model of a clinical trial? Why is a control group included in clinical trials? 4. In this activity, if a person finds that the sweetened pink lemon drink (the medicine) tastes worse than the yellow lemon drink, their headache is gone, but there are side effects. If the side effects were serious, such as a risk of serious heart problems, would you recommend selling the medicine to people suffering from headaches? Explain your decision. What are the trade-offs involved in your decision? 194 195 5. In this activity, if a person finds that the medicine tastes better or worse than the yellow lemon drink, their headache is gone. Review the results of this model. Think about whether the medicine works and how often side effects occur. What would you conclude about the safety and effectiveness of this medicine for treating headaches? Support your conclusion with evidence.196 6. Revisit the issue: How do the effects of the medicines described in this activity demonstrate interactions between body systems? 197198199 7. If you were considering participating in a clinical trial for a new medication, what questions would you ask? What information would you want to know? EXTENSION Ask your teacher to post your class data on the SEPUP Third Edition Body Systems page of the SEPUP website at www.sepuplhs.org/ middle/third-edition. Your teacher will show you the data posted by other students. How do your results compare? 190 NGCCCE1 191 NGSPEA2 192 NGSPAD1 193 SEASAD1 194 SEASET1 195 NGPEL13 196 ELWH681 197 SELTWD1 198 NGLS1A3 199 NGCCSM1
BODY 71 14 Evaluating Clinical Trials ta l k i n g i t o v e r I magine that you work for a large medicine manufacturer who wants to develop a new headache medicine. Your research teams have been developing and testing three promising medicines, but you only have enough money in your budget to keep developing one of them. Based on the data the researchers have gathered thus far, you must determine which medicine to keep developing. Conducting research and studies on new medicines is time-consuming and expensive. Medicine manufacturers will often develop and test several new possible medicines at the same time. However, it is too expensive to continue this process over the many years necessary to determine if a medicine is safe and effective. As the companies test the new medicines, they use the test results to decide which new medicines to move forward with and which medicines to stop developing. 200 For a headache medicine to work, it must be absorbed from your digestive system into your circulatory system, circulate to the part of your brain that is affected, and then block the changes that cause the pain. As these systems interact, it is possible for the medicine to cause side effects related to these systems or to other parts of your body. In this activity, you will analyze the side effects and other information about three possible new medicines to decide which medicine a company should continue developing. 200 NGCCNS1
ACTIVITY 14 EVALUATING CLINICAL TRIALS 72 BODY GUIDING QUESTION How can data be used to determine the best medicine to research and test? MATERIALS For each student 1 Student Sheet 14.1, “Reviewer Comments” PROCEDURE 1. With your group, brainstorm all the factors that are important in designing a safe and effective medicine. Work together to agree on a complete list. • Listen to and consider the explanations and ideas of other members of your group. • If you disagree about a factor with others in your group, explain to the rest of the group why you disagree. 2. Review the data in the first table on the next page, “Clinical Trial Results: Medicine A.” 3. Use your list of experimental design factors from Step 1 and Student Sheet 14.1, “Reviewer Comments,” to evaluate the results for Medicine A. Record the name of the medicine, positive results, negative results, and any other comments you have.201 4. Repeat Steps 2 and 3 for Medicines B and C. 5. With your group, choose one of the three medicines. Based on the clinical trial results for that medicine and what you’ve learned about how body systems interact, answer the following: a. Which body systems seem to be affected by the medicine? b. Which other body systems might be affected, based on how human body systems interact?202 6. Follow your teacher’s instructions to have a Walking Debate about which medicine should be funded for further research. 203 201 ELWH689 202 NGSPAD1 203 SELTWD1
EVALUATING CLINICAL TRIALS ACTIVITY 14 BODY 73 Clinical Trial Results: Medicine A Effectiveness of Medicine A: 52% of patients report that headache pain significantly diminished or disappeared after taking Medicine A. SIDE EFFECTS % OF PATIENTS REPORTING SIDE EFFECTS RESTRICTIONS ON PATIENTS USING MEDICINE (DUE TO SIDE EFFECTS) Severe nausea and vomiting 3% Cannot work or go to school Drowsiness 7% Cannot drive or operate heavy machinery Dizziness 5% Cannot drive or operate heavy machinery; 2% are unable to go to work or perform routine tasks at home Clinical Trial Results: Medicine B Effectiveness of Medicine B: 63% of patients report that headache pain significantly diminished or disappeared after taking Medicine B. SIDE EFFECTS % OF PATIENTS REPORTING SIDE EFFECTS RESTRICTIONS ON PATIENTS USING MEDICINE (DUE TO SIDE EFFECTS) Chest pain 10% Patients with heart conditions or risk of heart disease must discontinue use of Medicine B Pain in joints and/or bones 9% Cannot drive or operate heavy machinery; cannot do strenuous physical tasks Nausea 15% Must eat only mild or bland foods Clinical Trial Results: Medicine C Effectiveness of Medicine C: 35% of patients report that headache pain significantly diminished or disappeared after taking Medicine C. SIDE EFFECTS % OF PATIENTS REPORTING SIDE EFFECTS RESTRICTIONS ON PATIENTS USING MEDICINE (DUE TO SIDE EFFECTS) Dry mouth 5% None; recommend increasing water consumption Slight nausea 4% Must avoid spicy foods
ACTIVITY 14 EVALUATING CLINICAL TRIALS 74 BODY ANALYSIS 1. Choose the medicine that you think should be recommended for continued development. Answer the following questions for that medicine: 204 a. Why are you recommending that medicine over the other two? Explain your reasoning. b. What are the trade-offs associated with the medicine you are recommending?205206207 2. Revisit the issue: Which systems are likely to have side effects from taking the three medicines in this activity? Explain.208209210 3. Imagine that you are someone who suffers from severe headaches. You are considering participating in the clinical trials this company is doing with the medicines listed above. What questions would you have? What other information would you want to know about the medicine before you agree to participate in the clinical trial? 204 SEASAR1 205 NGPEL13 206 NGSPEA2 207 ELWH681 208 NGLS1A3 209 NGCCCE1 210 NGCCSM1
BODY 75 Body Systems u n i t s u m m a r y The human body has many organs—structures composed of one or more tissues that have a specific function, or functions. Several organs working together form a system. Human bodies contain many systems, including the following: SYSTEM FUNCTION Muscular Supports the body and helps it move Skeletal Supports the body, helps it move, and protects vital organs from injury Nervous Sends and receives messages from the body Digestive Breaks down food and absorbs nutrients and energy Excretory Gets rid of wastes Respiratory Takes in oxygen and gets rid of carbon dioxide Circulatory Uses blood to move nutrients, wastes, oxygen, and carbon dioxide around the body Body System Functions Your digestive system’s main function is to break down food and absorb the nutrients and energy from the food. It does this using both chemical and mechanical digestion. Chewing mechanically breaks the food into smaller pieces and adds saliva to start chemical digestion. The food travels through your esophagus to your stomach, where muscle contractions and acid in the stomach continue to break down the food. When food reaches your small intestine, more chemicals from your liver and pancreas are added. Nutrients are absorbed from your digestive system into your circulatory system to move to where they are needed in your body. Finally, your large intestine absorbs water and some vitamins from the food, and then rids your body of the waste through the rectum and anus. Foods contain a mixture of carbohydrates, fats, and proteins. These substances break down into smaller subunits—sugars, fatty acids, and amino acids—that can be used by the body. Your body gets energy and matter—the physical substances—from these subunits. Your nervous system responds to stimuli from your environment. For example, it responds when you step on a sharp rock. The nerves in
UNIT SUMMARY 76 BODY your body take in information from your sensory neurons and send that information through interneurons in your spinal cord. If the information travels to your brain, the brain processes the information and sends messages through motor neurons out to systems in your body, such as your muscular and skeletal systems, to respond to the information. Your brain can also store the information as memories. Sometimes messages go straight from your spinal cord to your motor neurons so that you respond very quickly, such as when you touch a hot stove. Body System Interactions Human body systems work together in many ways. Your circulatory system and respiratory system work together to bring oxygen into your body and move it to every cell in your body. Similarly, these systems work together to take carbon dioxide from the cells in your body and return it to your lungs to be exhaled. When you exercise, your heart rate increases and moves the blood around your body faster to deliver more oxygen to your cells and remove the increased amount of carbon dioxide. Every single cell in your body experiences this exchange of gases; gases move to and from cells via the smallest blood vessels in your body—capillaries. Capillaries connect to the veins and arteries in your circulatory system, which bring the blood to and from the lungs. Medicines and Body Systems Sometimes human body systems do not work properly. When this happens, it can affect many body systems at once. The disease pellagra is caused by poor diet, but it does not affect just the digestive system. It also affects the nervous system and other parts of the body. Scientists study diseases like pellagra to understand more about how body systems work together. Scientists study diseases and medicines used to treat diseases by doing clinical trials. In these clinical trials, they gather data about how the disease or the medicine affects different body systems. Scientists examine the data to help understand more about what they are studying. For example, scientists look at side effects in patients taking a new medicine. They study how serious the side effects are and what percentage of the patients experience them. They also look at how effective the new medicine is at treating the patient.
UNIT SUMMARY BODY 77 Key Vocabulary carbohydrate circulatory system clinical trial digestion digestive system evidence function nervous system neuron organ protein respiratory system stimuli structure
BODY 79 THE NATURE OF SCIENCE AND ENGINEERING I f someone asked you the question, “What is science?” how would you answer? You might reply that it is knowledge of such subjects as Biology, Chemistry, Earth Science, and Physics. That would be only partly correct. Although science is certainly related to the accumulation and advancement of knowledge, it is much more than that. Science is a way of exploring and understanding the natural world. According to the American Association for the Advancement of Science (AAAS), two of the most fundamental aspects of science are that the world is understandable and that scientific ideas are subject to change. Scientists believe that the world is understandable because things happen in consistent patterns that we can eventually understand through careful study. Observations must be made and data collected for us to discover the patterns that exist in the universe. At times scientists have to invent the instruments that allow them to collect this data. Eventually, they develop theories to explain the observations and patterns. The principles on which a theory is based apply throughout the universe. When new knowledge becomes available, it is sometimes necessary to change theories. This most often means making small adjustments, but on rare occasions it means completely revising a theory. Although scientists can never be 100% certain about a theory, as knowledge about the universe becomes more sophisticated most theories become more refined and more widely accepted. You will see examples of this process as you study the history of scientists’ understanding of such topics as elements and the periodic table, the cellular basis of life, genetics, plate tectonics, the solar system, and the universe in this middle school science program. A Science and Engineering a p p e n d i x
APPENDIX A 80 BODY While the main goal of science is to understand phenomena, the main goal of engineering is to solve problems. Like science, engineering involves both knowledge and a set of practices common across a range of engineering problems. Just as scientists start by asking questions, engineers start by defining problems. Just as scientists search for explanations for phenomena, engineers search for solutions to problems. Science and engineering often build on each other. For example, scientists use instruments developed by engineers to study the natural world. And engineers use scientific principles when designing solutions to problems. Scientific Inquiry Inquiry is at the heart of science, and an important component of inquiry is scientific investigation, including experimentation. Although scientists do not necessarily follow a series of fixed steps when conducting investigations, they share common understandings about the characteristics of a scientifically valid investigation. For example, scientists obtain evidence from observations and measurements. They repeat and confirm observations and ask other scientists to review their results. It is important for scientists to avoid bias in designing, conducting, and reporting their investigations and to have other unbiased scientists duplicate their results. Some types of investigations allow scientists to set up controls and vary just one condition at a time. They formulate and test hypotheses, sometimes collecting data that lead them to develop theories. When scientists develop theories they are constructing models and explanations of the patterns and relationships they observe in natural phenomena. These explanations must be logically consistent with the evidence they have gathered and with evidence other scientists have gathered. Hypotheses and theories allow scientists to make predictions. If testing turns out to not support a prediction, scientists may have to look at revising the hypothesis or theory on which the prediction was based. Engineering Design An engineer uses science and technology to build a product or design a process that solves a problem or makes the world better. Engineering design refers to the process engineers use to design, test, and improve solutions to problems. Like scientists, engineers design investigations to test their ideas, use mathematics, analyze their data, and develop models.
APPENDIX A BODY 81 Since most solutions in the real world are not perfect, engineers work to develop the best solutions they can, while balancing such factors as the function, cost, safety, and usability of their solutions. The factors engineers identify as important for solutions to a problem are called criteria and constraints. Most engineering solutions have one or more trade-offs—desired features that must be given up in order to gain other more desirable features. Science as a Human Endeavor Science and engineering are human activities. People from all over the world engage in science and engineering and use scientific information and technological solutions. The types of questions a scientist asks and the types of problems an engineer tries to solve are influenced by what they think is important. And what they think is important to investigate often depends on their background, experiences, and perspective. This is why it is essential for all types of people to become scientists and engineers—to be sure science and engineering respond to their interests and needs and to be sure that there are diverse ideas to enrich explanations and arguments. Participation by a wide variety of people in science and engineering will lead to greater and swifter progress toward understanding how the natural world works and solving problems facing individuals, communities, and the environment. Visit the SEPUP Third Edition page for each unit of the SEPUP website at www.sepuplhs.org/middle/third-edition to learn more about the interests and accomplishments of diverse scientists and engineers. Each unit highlights examples of people from varied backgrounds in careers that contribute to and depend on the advancement of science and technology. References American Association for the Advancement of Science (AAAS). (1990). Project 2061: Science for all Americans. Oxford University Press. National Research Council. (2012). A Framework for K–12 Science Education: Practices, Crosscutting Concepts, and Core Ideas. Committee on a Conceptual Framework for New K–12 Science Education Standards. Board on Science Education, Division of Behavioral and Social Sciences and Education. The National Academies Press.
APPENDIX A 82 BODY B Science Safety SCIENCE SAFETY GUIDELINES You are responsible for your own safety and for the safety of others. Be sure you understand the following guidelines and follow your teacher’s instructions for all laboratory and field activities. Before the Investigation • Listen carefully to your teacher’s instructions, and follow any steps recommended when preparing for the activity. • Know the location and proper use of emergency safety equipment, such as the safety eye-and-face wash, fire blanket, and fire extinguisher. • Know the location of exits and the procedures for an emergency. • Dress appropriately for lab work. Tie back long hair and avoid wearing dangling or bulky jewelry or clothing. Do not wear opentoed shoes. Avoid wearing synthetic fingernails—they are a fire hazard and can tear protective gloves. • Tell your teacher if you wear contact lenses, have allergies to latex, food, or other items, or have any medical condition that may affect your ability to perform the lab safely. • Make sure the worksurface and floor in your work area are clear of books, backpacks, purses, or other unnecessary materials. • Ask questions if you do not understand the procedure or safety recommendations for an activity. • Review, understand, and sign the Safety Agreement, and obtain the signature of a parent or guardian. a p p e n d i x
APPENDIX B BODY 83 During the Investigation • Carefully read and follow the activity procedure and safety recommendations. • Follow any additional written and spoken instructions provided by your teacher. • Use only those activities and materials approved by your teacher and needed for the investigation. • Don’t eat, drink, chew gum, or apply cosmetics in the lab area. • Wear personal protective equipment (chemical splash goggles, lab aprons, and protective gloves) appropriate for the activity. • Do not wear contact lenses when using chemicals. If your doctor says you must wear them, notify your teacher before conducting any activity that uses chemicals. • Read all labels on chemicals, and be sure you are using the correct chemical. • Keep chemical containers closed when not in use. • Do not touch, taste, or smell any chemical unless you are instructed to do so by your teacher. • Mix chemicals only as directed. • Use caution when working with hot plates, hot liquids, electrical equipment, and glassware. • Follow all directions when working with live organisms or microbial cultures. • Be mature and cautious, and don’t engage in horseplay. • Report any unsafe situations, accidents, or chemical spills to your teacher immediately. • If you spill chemicals on your skin, wash it for 15 minutes with large amounts of water. Remove any contaminated clothing and continue to rinse. Ask your teacher if you should take other steps, including seeking medical attention. • Respect and take care of all equipment.
APPENDIX B 84 BODY After the Investigation • Dispose of all chemical and biological materials as instructed by your teacher. • Clean up your work area, replace bottle caps securely, and follow any special instructions. • Return equipment to its proper location. • Wash your hands with soap and warm water for at least 20 seconds after any laboratory activity, even if you wore protective gloves. Your teacher will give you an agreement similar to the one below to sign. Science Safety Agreement STUDENT I, _________________________, have read the attached Science Safety Guidelines for students and have discussed them in my classroom. I understand my responsibilities for maintaining safety in the science classroom. I agree to follow these guidelines and any additional rules provided by the school district or my teacher. Student Signature________________________________________________________________________ Date_____________________ PARENT OR GUARDIAN Please review with your student the attached Science Safety Guidelines, which include the safety responsibilities and expectations for all students. It is important that all students follow these guidelines in order to protect themselves, their classmates, and their teachers from accidents. Please contact the school if you have any questions about these guidelines. I, _________________________, have read the attached guidelines and discussed them with my child. I understand that my student is responsible for following these guidelines and any additional instructions at all times. Parent or Guardian Signature_____________________________________________________________ Date_____________________
APPENDIX A BODY 85 Th e fo llow i n g pag e s include instructional sheets that you can use to review important science skills: • Reading a Graduated Cylinder • Using a Dropper Bottle • Bar Graphing Checklist • Scatterplot and Line Graphing Checklist • Interpreting Graphs • Elements of Good Experimental Design • Using Microscopes C Science Skills a p p e n d i x
APPENDIX C 86 BODY READING A GRADUATED CYLINDER A graduated cylinder measures the volume of a liquid, usually in milliliters (mL). To measure correctly with a graduated cylinder: 1. Determine what measurement each unmarked line on the graduated cylinder represents. 2. Set the graduated cylinder on a flat surface and pour in the liquid to be measured. 3. Bring your eyes to the level of the fluid’s surface. (You will need to bend down!) 4. Read the graduated cylinder at the lowest point of the liquid’s curve (called the meniscus). 5. If the curve falls between marks, estimate the volume to the closest milliliter. The example below shows a plastic graduated cylinder that contains 42 mL of liquid. 50 40
APPENDIX C BODY 87 USING A DROPPER BOTTLE Incorrect Holding the dropper bottle at an angle creates drops that vary in size. Correct Holding the dropper bottle vertically creates drops that are more consistent in size.
APPENDIX C 88 BODY BAR GRAPHING CHECKLIST Sample Graph Follow the instructions below to make a sample bar graph. Start with a table of data. This table represents the amount of Chemical A that the Acme Company used each year from 2011 to 2015. Determine whether a bar graph is the best way to represent the data. Draw the x- and y-axes for the graph. Label them with the names and units of the data. Decide on a scale for each axis. Be sure there is enough space for all the data and that it’s not too crowded. Mark intervals on the graph, and label them clearly. Year Chemical A used (kg) 2011 2013 2014 2012 2015 100 110 80 90 105 Year Chemical A (kg) Year axis: 1 block = 1 year Chemical A axis: 1 block = 20 kilograms Year Chemical A (kg) 120 0 40 20 60 80 100 2011 2012 2013 2014 2015
APPENDIX C BODY 89 BAR GRAPHING CHECKLIST (continued) Plot your data on the graph. Fill in the bars. Title your graph. The title should describe what the graph shows. Year Chemical A (kg) 120 0 40 20 60 80 100 2011 2012 2013 2014 2015 Year Chemical A (kg) 120 0 40 20 60 80 100 2011 2012 2013 2014 2015 Year Chemical A (kg) 120 0 40 20 60 80 100 2011 2012 2013 2014 2015 Amount of Chemical A used 2011–2015
APPENDIX C 90 BODY Sample Graph Follow the instructions below to make a sample graph. Start with a table of data. Determine whether a line graph or a scatterplot is the best way to represent the data. Draw the x- and y-axes for the graph. Label them with the names and units of the data. Decide on a scale for each axis. Be sure there is enough space for all the data and that it’s not too crowded. Draw intervals on the graph, and label them clearly. SCATTERPLOT AND LINE GRAPHING CHECKLIST Time (minutes) Distance (meters) 0 2 3 1 4 0 9 5 16 20 5 27 MOTION OF A BALL LINE GRAPH Time (minutes) Distance (meters) Time axis: 1 block = 1 minute Distance axis: 1 block = 5 meters Time (minutes) Distance (meters) 30 0 10 5 15 20 25 0 1 2 3 4 5