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Teaching Guide
guide title
Exploring Vessel Physics
Mirrored Movements
A Healthy Diet
Quiz
image of apple
Started over a half century ago, the Framingham Heart Study has provided much of what science knows today about the risks associated with heart disease. Today, the survey also uses high-tech imaging procedures such as MRI to obtain a non-invasive look at the heart and blood vessels. In the segment "How's Your Heart?", you saw how this technique can uncover the buildup of deadly plaque within the aorta. One of the primary causes of heart disease is a high-fat diet. How well do you eat? Do your meals follow the guidelines for healthy diets suggested by the American Heart Association? There's one way to find out.

note to educators
 


OBJECTIVE
This activity page will offer:

  • A a real world connection to diet and health
  • An opportunity to develop proactive behavior that will maintain good health
  • An experience in collecting and analyzing data, and drawing conclusions

Part 1- Constructing The Challenge

MATERIALS

  • Gum drops
  • Toothpicks

PROCEDURE

  1. Work with a partner.
  2. Assign one color of gumdrop to a specific type of atom.
  3. Use the illustrations below as a guide to construct models of the molecular backbone of saturated and unsaturated fats. One student constructs the saturated backbone, while the other constructs the unsaturated version

QUESTIONS

Section of a Saturated Fat Molecule
saturated fat molecule

Section of an Unsaturated Fat Molecule

unsaturated fat molecule

  1. How many bonds does each carbon atom form?
  2. How many bonds does each hydrogen atom form?
  3. How does the structure of saturated fat differ from the unsaturated fat?
  4. Why do you think that the terms saturated and unsaturated are applied to these molecular backbones?

Saturated fats (due to their molecular shape) tend to be solid at room temperature, whereas unsaturated fats tend to stay in liquid form. Remember the image of the blocked aorta you saw in the program? The plaque that accumulates within blood vessels appears to be related to the properties of solid saturated fats. Liquid fats seem to flow through the vessels without reacting to form the wall deposits.

MATERIALS

  • Recording Sheet
  • Pen

recording sheet

PART 2 - Recording Your Diet


  1. In order to obtain a valid representation of your eating habits, you should perform this survey over three days. So get ready and keep a pen and recording sheet nearby.
  2. Prior to each meal, examine the labels of the food you are about to eat. Then, record the following information on your diet sheet. Remember to calculate the total quantities based upon serving size. If you having a difficult time in determining the nutritional composition of foods, check out this incredible online database offered by the US Department of Agriculture (NOTE: Be sure to click "Report" for a complete list of nutrients for each item you enter.)
  3. Make sure to record the information about all of the food you consume including between-meal snacks. At the end of the day, add up each of the columns and record your daily totals.
  4. At the end of the third day, calculate the average for each of these four values.

PART 3- How Healthy Is Your Diet?

  1. Calculate 10 percent of your total calories. Record that number. The value you recorded for your saturated fat intake should be less than this number. If it's not, your intake of saturated fat is too high.
  2. Calculate 30 percent of your total calories. The value you record for your total fat should be less than this number. If it's not, your intake of total fat is too high.
  3. What was your average daily intake of dietary cholesterol? If it was greater than 200 milligrams per day, then your intake of dietary cholesterol is too high.

QUESTIONS

  1. How did your nutrient intake compare with the guidelines set by the American Heart Association?
  2. Suppose you have an unhealthy intake of these nutrients. Is knowing that you have a poor diet sufficient enough to change your eating habits? Why or why not? What type of information or what event might change the way you eat?

A Worrisome Analysis

Now that you've calculated your dietary intake for several nutrients, how do you feel about your current diet? Is it within healthful bounds? Is it worrisome? If you are concerned about your diet (or the diet of someone you know), check with your teacher or school health professional. They will be able to direct you to the best path of dietary counsel.

Web Connection

National Heart, Lung, and Blood Institute
extensive coverage of the Framingham Study.

The Heart Information Network offers a wealth of the latest heart news and information.

MRI atlas of the heart and aorta, showing healthy and diseased specimens.

American Heart Association
coverage of risk factors associated with heart disease.

answers

The activities in this guide were contributed by Michael DiSpezio, a Massachusetts-based science writer and author of "Critical Thinking Puzzles" and "Awesome Experiments in Light & Sound" (Sterling Publishing Co., NY).

Academic Advisors for this guide
Corrine Lowen, Science Department, Wayland Public Schools, Wayland, MA
Suzanne Panico, Science Department, Fenway High School, Boston, MA

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