Lesson SixteenThe Heart Meets Resistance

• Use a model to explore how the diameter of a tube affect circulation• Examine affects of narrow or hardened arteries

What is blood pressure? What are some things that could increase or decrease blood pressure?(go over bellwork and relate BP to a water hose w/ and w/o a thumb over the end) Read Introduction p 138 (Class discussion of pictures. Students will almost certainly have some “war” stories to share about family experiences.)

How does the diameter of a tube affect how hard a pump must work to circulate water?

If the diameter of a tube ____, then a pump would have to work ______ to circulate water because ___________

Siphon-pumps, cups, rubber stopper with a small hole and one with a large hole, stopwatch

Inquiry 16.1 p. 139

1. Place both ends of a siphon pump in a cup of water

2. Count the number of times you can squeeze in 15 sec

3. Switch with your partner, repeat and average the number

4. Insert the large hole stopper and repeat the test with both partners and average.

5. Insert the small hold stopper and repeat the test with both partners and average.

(pay attention to step 3 C – make sure fingers and thumb meet through the bulb each time you squeeze. Stress consistency)

Design your data table for this lab (must be approved)

Answer the question using data and restate your hypothesis

Answer questions A-F under step 7

ReflectionsQuestions refer back to introduction and bellwork

(factors affecting BP in TM on pg 186-187)

blood pressure atherosclerosis

Sphygmomanometer stroke

hypertension aneurysm

Read “Blood Pressure: What Goes Up Should Come Down” p 142 in SG

Summarize circulation in the heart and blood vesselsExtensions 1 and 3 (TM pg 188)

(Student study guide 16.1)