Activity 1 - EKG p.9
Activity 2 - Heart Rate p.13
Activity 3 - Blood Pressure p.15
Activity 4 - Breathing Rate p.16

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I. TEACHER NOTES & GUIDELINES

TITLE OF LAB: Measuring Your Cardiovascular Function

DEVELOPERS OF LAB: Carrie Arnold JD555, Jim Clinton JD865, Madeleine Ferren JD882, Elisa Jury JD897, Barbara Lalli JD804, Karen Mayer JD564, Frank White JD809, Glenn Meyer JD569, Mary-Jo Albano JD552, Darlene Brown JD810, Elizabeth Cuesta JD712, Barbara Nicolato JD732.

OVERVIEW OF LAB:

DESCRIPTION
This major lab consists of 4 separate activities on cardiovascular function that can be used alone or in any combination. Activity 1 deals with measuring EKG, Activity 2 deals with measuring Heart Rate, Activity 3 deals with measuring Blood Pressure, and Activity 4 deals with measuring Breathing Rate. All 4 activities provide an introduction on how to perform these simple procedures to obtain data, provide a basis for learning how to use the scientific equipment involved, and learn what the "numbers" or "graphs" mean. This can lead students into an inquiry based lab approach as to what factors may change an EKG, Blood Pressure, Heart Rate, or Breathing Rate. (Such factors may include a persons gender, age, athlete vs. non-athlete, drugs - such as caffeine or exercise.) It may also lead students into inquiry based labs as to the relations between two or more of the variables looked at in these labs. For example, if exercise is done prior to doing these 4 activities, what affect will this exercise have on EKG, Heart Rate, Breathing Rate, and EKG.
Each lab may require up to a five (5) period block of time as follows:
1/2 period - Elicit prior knowledge and misconceptions
2 periods - Work with computer and other instruments; record data
1/2 period - Students will design their own experiments
2 periods - Run student generated labs, discussion of results, application, and assessment

CURRICULUM CONSIDERATIONS
This lab will ideally fit into any General or New York State Regents Biology curriculum. This lab can also be used in AP or College Biology Programs.

These activities are designed for use with the Human Physiology topic in the NYS Biology Syllabus - specifically, Transport mechanisms, structure and function (heart). In the new Living Environment Core Curriculum-Draft, these labs align themselves with Performance Indicator 1.2. They also address standard numbers 1, 2, and 5 of the Learning Standards for Mathematics, Science and Technology.

REAL WORLD APPLICATIONS
All activities are directly related to real world applications. A student's blood pressure, heart rate, breathing rate and/or EKG may be taken at sometime in the near future (if not already done). Students will now be able to understand for themselves what the terms and "numbers" mean. They may also gain some understanding of the inter-relatedness of these cardiovascular functions.

SAFETY CONSIDERATIONS
For safety of students and equipment, all directions must be followed exactly as given. Special attention should be paid to the following:

· Follow the general safety guidelines for your particular school.
· For safety of students and equipment, all directions must be followed exactly as given.
· Treat all equipment with care. They are finely tuned instruments and should be handled as such.
· For all of the activities described, make sure the student removes the sensors before moving from their seats.
· Some activities may require a person whose cardiovascular functioning will be monitored to perform some exercise (e.g., jogging in place) for several minutes. Do not perform this activity if vigorous activity will cause discomfort or be hazardous to the health of the person.

OBJECTIVES:

1. Utilize computer based technology to investigate a living system.
2. Collect and graph data on Heart Rate.
3. Design an experiment to measure the effect of various stimuli on Heart Rate.
4. Compare the results obtained and suggest why various factors effect Heart Rate.
5. Collect, graph and interpret data from an EKG recording.
6. Describe a typical EKG and relate what all the "bumps" mean.
7. Design an experiment to measure the effect of various stimuli on an EKG.
8. Collect and interpret Blood Pressure.
9. Design an experiment to measure the effect of various stimuli on Blood Pressure.
10. Collect and interpret Breathing Rate data.
11. Design an experiment to measure the effect of various stimuli on Breathing Rate.
12. Design experiments to see how one variable (such as heart rate) may affect another variable (such as breathing rate or blood pressure).
13. Defend or refute prior ideas concerning cardiovascular function.

BACKGROUND INFORMATION

A. SCIENTIFIC VIEWPOINT
In the first activity, the EKG sensor will measure the electrical current associated with the polarization and depolarization of heart muscle tissue during heart contractions. The Science Workshop program records and displays the EKG (heart voltage signal) produced by the heart as the chambers contract. One part of a typical EKG is a "flat line" or trace indicating no detectable electrical activity. This line is called the isoelectric line. Deviation from this line indicates electrical activity of the cardiac muscle. The first deviation from the isoelectric line in a typical EKG is an upward peak followed by a return to the isoelectric line. This wave is called the P wave. The P wave is caused by the depolarization of the atria and is associated with the contraction of the atria. This will be measured by the P-R interval in the lab. Following atrial contraction, there is a downward trough called the Q wave. Shortly after the Q wave, there is a rapid upswing of the line called the R wave followed by a strong downswing of the line called the S wave and then a return to the isoelectric line. These three waves together are called the QRS complex. This complex is associated with the contraction of the ventricles which occurs immediately after the curve is recorded. This will be measured by the QRS interval in the lab. After a short period of time the ions that have been involved in the contraction migrate back to their original locations. The movement of these ions generates an upward wave that then returns to the isoelectric line. This upward peak is called the T wave and represents ventricular recovery. The complete electrical activity on the ventricals (which includes the QRS complex and the T wave) will be measured by the Q-T interval in the lab.

In the second activity, the Heart Rate Sensor will measure heart rate. Every beat of your heart sends blood flowing through arteries, capillaries and veins. All day and night the heart's rhythmic contractions pump blood to all parts of the body. The heart keeps the blood circulating to deliver oxygen and food to the cells and to remove wastes. If circulation stops, even for a short time, the cells deteriorate to the point that they will not survive. Heart rate is one of several measurable statistics that can be used to determine an individual's cardiovascular health. The average heart rate for a teenager is 70 beats per minute. It is important to remember that individual heart rates will vary greatly from person to person and factors affecting heart rate include gender, weight, genetics, emotional state, physical fitness and medication.

In the third activity, Blood Pressure will be taken with a sphygmomanometer. Blood pressure is a measurement of the force of blood against the walls of the arteries. There are two measurements to a blood pressure reading (e.g., 120/80). The first number is called the systolic pressure and the second number is diastolic pressure. The systolic pressure represents the pressure in the arteries when the ventricles contract and pumps blood from the heart to the lungs and to the rest of the body. The normal range of the systolic pressure is from 90-130. The diastolic pressure is the pressure in the arteries between ventricular contractions. The normal range of the diastolic pressure is from 60-89.

In the fourth activity, respiration rate will be taken with a Breathing Rate Sensor. Breathing rate is defined as the number of breaths taken per minute. Respiration rate depends on several factors: altitude, lung capacity, health, and level of activity. Higher altitudes and levels of activity would tend to increase respiration rates. Larger lung capacity and generally good health would tend to decrease respiration rate.

EQUIPMENT/MATERIALS PROVIDED BY SOTM ALL LABS: laptop computers PASCO interfaces w/ cables ACTIVITY 1 EKG sensors electrode patches (3 per student) ACTIVITY2 Heart Rate sensors ACTIVITY 3 Blood Pressure Digital Monitor ACTIVITY 4 Breathing Rate sensors

PROVIDED LOCALLY (These depend on student design but suggested materials for some design options are given.) coffee (caffeinated) milk sugar caffeinated soda (i.e. Pepsi, Coke) caffeine free soda chocolate bars area to exercise

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