Question

Procedure
1. Use the permanent marker to label the plastic bottles 1 and 2.
2. Use a nail to carefully puncture two holes in the side of each bottle (approximately 3.5 cm from the bottom
of the bottle) so that the holes are across from each other and at the same height from the bottom of the
bottle. It is best to puncture the bottle with the nail straight through both sides. This will help keep the
holes level.
3. You may need to maneuver the nail around the hole to make it large enough to fit the plastic tubing
(Figure 8). The goal is for the tubing to fit tightly in the hole.

4. Carefully cut the 60 cm tubing into four equal lengths of 15 cm.
5. Attach one end of one piece of 15 cm tubing to the OUT end of a
check valve.
6. Attach one end of a second piece of tubing to the IN end of the
check valve.
7. Repeat Steps 3 and 4 for the remaining check valve.
8. Construct a closed system by inserting the free ends of the tubes
into the holes you created in the plastic bottles to create a loop. The
tubes should be far enough into the bottle so that water can flow from tube to bottle to tube. The tubes in
each bottle should not touch (Figure 9).
Note: Properly assembled models should have the direction of the check valves facing in opposite di
rections.
9. Fill each bottle ¾ with water. The water level should be higher than the tubing.
10. Place the model on an underpad or paper towel to protect surfaces for the next step. This will also help
catch water that leaks from the model. There should be minimal leaking if tubes are tightly secured in the
bottles.
11. Place one drop of dye in each bottle and close the bottle by screwing on the caps.
12. Gently swirl the bottles to allow dye and water to mix. Be careful not to squeeze the bottles!
13. Note where the water is initially before squeezing the bottles and record your observations in Table 3.
14. Squeeze bottle 1 with both hands. Observe the direction of water flow and the water level in each bottle
while you are squeezing and right after you stop squeezing. Record your observations in Table 3.
15. Repeat Step 13 for the bottle 2 and record your observations.
16. Squeeze one bottle and then the other back and forth. Observe the direction of water flow and the water
level in each bottle. Record your observation in Table 3.

Question 1) Describe the water level and the direction of water flow in your heart model at each stage listed below.

Cardiovascular System Experiment

1. Squeezing bottle 1

2. Directly after squeezing bottle 1

3. Squeezing bottle 2

4. Directly after squeezing bottle 2

5. Squeezing bottle 1 and 2 back and forth

Question 2) What did each of the bottles represent? What does the water represent?

Answer 1

1) Squeezing no 1 bottle the level of water and flow is 4.5cm and flow is anticlock wise'.

2) After squeezing bottle 1 the level of water and flow of liquid is 4.8cm and their will be no flow.

3)Squeezing bottle number 2 the level of water and flow of liquid is 4cm anticlockwise,

4) While directly squeezing bottle no 2 the level of water and flow of liquid is 4.3 cm and no flow is observed,

5) while squeezing Bootle no 1 and 2 in back and forth direction it is 4 to 4.6 cm in circle and anticlockwise.

The bottle represents chambers of heart while the water represents blood flowing through it.