Download Heart muscle tissue contracts and relaxes to pump blood throughout

Name __________________________
Date _______
Period _______
Lab # _________ - Human Heart Lab
Heart muscle tissue contracts and relaxes to pump blood throughout your body. The blood, carrying oxygen
and other materials, moves through the circulatory system which is composed of arteries, capillaries and
veins.
In this investigation, you will:
 Follow the pathway of blood through the heart.
 Determine the amount of oxygen or carbon dioxide contained in blood in each side of the heart.
 Follow the sequence of events occurring as a heart beats.
 Measure blood pressure differences in arteries and veins using a heart-blood vessel model.
Materials:
 Plastic bottle
 2-hole stopper to fit bottle
 Metric ruler
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Glass tube, 3 cm long
Glass tube, 18 cm long
Glass tube, 16 cm long
Procedure:
Part A. Heart Anatomy and Blood Flow
Study Figure 1 to determine the names and
locations of all major blood vessels and heart
structures. This diagram is a front view of the
heart, which makes the labels indicating left and
right sides appear to be reversed. All shaded areas
are muscle. Unshaded areas are filled with blood.
Complete Table 1 indicating the direction of blood
flow.
Part B. Condition of Blood as it Flows Through the
Heart
All vessels bringing blood to the heart’s right side and
leaving from the right ventricle contain blood that is
deoxygenated. Deoxygenated blood is low in oxygen
and high in carbon dioxide.
All vessels bringing blood to the heart’s left side and
leaving from the left ventricle contain oxygenated
blood. Oxygenated blood is high in oxygen and low in
carbon dioxide.
1. Blood moves to two organs from the right side of
the heart. What are these organs?
Complete Table 2 indicating the oxygen content of
blood. Use the terms “deoxygenated” and
“oxygenated.” Refer to Figure 1 for help.
2. Blood is received from two organs on the left
side of the heart. What are these organs?
3a. Describe the condition of blood in all parts of the
right side of the heart.
3b. Describe the condition of blood in all parts of the
left side of the heart.
Aorta – Blood to Body
Pulmonary Artery – Blood to Left Lung
Superior Vena Cava – Blood from upper body
Pulmonary Artery – Blood to Right Lung
Pulmonary Vein – Blood from Right Lung
Pulmonary Vein – Blood from Left Lung
Left Atrium
Right Atrium
Bicuspid Valve
Tricuspid Valve
Semilunar Valves
Right Ventricle
Left Ventricle
Inferior Vena Cava – Blood from lower body
RIGHT
Table 1 – Blood Flow
Receives Blood From
Left
Side
1.
2.
FIGURE 1
LEFT
Table 2 – Oxygen Content of Blood
Chamber or Vessel
Oxygenated or
Deoxygenated
Left Ventricle
Right Ventricle
Left Atrium
Right
Side
Left
Side
Right
Side
1.
2.
Right Atrium
Pulmonary Artery
Pulmonary Vein
Pumps Blood To
Superior Vena
1.
Cava
2.
1.
2.
Inferior Vena Cava
Aorta
Part C. Heart Pumping Action
In order to move blood through the heart, a
pumping action must occur. It is the ventricles
that aid in the pumping action of the heart. Heart
valves keep the blood flowing in one direction as
the ventricles squeeze or pump blood through
the heart.
Examine Figure 2 showing the ventricles relaxed
and not pumping blood. This relaxed condition is
called diastole.
Complete the left column of Table 3 while looking
at Figure 2.
Examine Figure 3 showing the ventricle sides
pushing in and squeezing and pumping blood out
of the heart. This pumping action is called
systole.
Complete the right column of Table 3 by looking
at Figure 3.
4. (a) During diastole, are the ventricles filling or
being emptied of blood?
Table 3
Ventricles In
Diastole
Systole
Relaxed or pumping
Bi- and tricuspid valves
open or closed? *
Blood flowing past bi- and
tricuspid valves?
Blood flowing into
ventricles from atria?
Semilunar valves open or
closed?*
Blood flowing past
semilunar valves?
Blood flowing out of
ventricles into aorta or
pulmonary artery?
*Valves are open if their tips are not touching.
A continuous pattern of diastole and systole allows
the heart to pump blood to all parts of the body. The
heart relaxes a little and fills with blood, then pumps.
It relaxes again while it refills, and then pumps again.
You detect this pattern of relaxing and pumping
when you feel your pulse.
(b) During systole, are the ventricles filling or
being emptied of blood?
FIGURE 2 (DIASTOLE)
FIGURE 3 (SYSTOLE)
Part D. Blood Pressure Model
Blood is under pressure as the heart pumps it
through your body. The amount of pressure,
however, varies throughout your body. Blood vessels
called arteries have thicker walls and are less flexible.
Arteries have blood under high pressure. Other blood
vessels, veins, have blood under low pressure
because of their thinner, more flexible walls and
because of the loss of pressure that occurs as blood
passes through the capillaries.
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
Secure a plastic bottle from your teacher.
Fill it with water and seal it with the provided
rubber stopper and tube assembly. The finished
apparatus should look like Figure 4. Note that
one of the tubes leading from the stopper is glass
while the other is plastic.
5. (a) Which tube represents the flexible blood
vessel?
(b) Which tube represents the inflexible blood
vessel?
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Position the plastic bottle assembly on a counter.
Place a metric ruler next to the bottle.
Give the plastic bottle one firm squeeze. Measure
the distance (in mm) that the water streams shoot
out the ends of the tubes.
Record the distances in Table 4 using the Trial 1
row.
Repeat the squeezing and measuring four more
times. Calculate an average distance for each
tube.
Table 4 – Experimental Results
Glass Tube
Plastic Tube
Trial 1
Trial 2
Trial 3
Trial 4
Trial 5
Average
Distance
A tube having more flexible sides will have a lower
pressure. A tube having less flexible sides will have a
greater pressure. The higher the pressure, the farther
a stream of water will shoot from a tube. The lower
the pressure, the shorter a stream of water will shoot
from a tube.
6. (a) Which tube has the longer average stream of
water?
(b) Which tube has the shorter average stream of
water?
7. (a) Which tube has the higher pressure within it?
(b) Which tube has the lower pressure within it?
8. (a) Which tube represents an artery?
(b) Which tube represents a vein?
Analysis (use complete sentences to answer the questions below)
1. Define the following terms:
Oxygenated blood _________________________________________________________
Deoxygenated blood _______________________________________________________
Systole _________________________________________________________________
Diastole ________________________________________________________________
2. Blood is changed from an oxygenated to a deoxygenated condition or vice versa in the circulatory
system. Which change occurs in lung capillaries? __________________________
_______________________________________________________________________
Which change occurs in body capillaries? _________________________________________
_______________________________________________________________________
3. Using Figure 1 as a guide, tell where blood goes when it leaves the:
Aorta __________________________________________________________________
Pulmonary artery __________________________________________________________
Right and left atria ________________________________________________________
4. Using Figure 1 as a guide, tell where blood comes from in each of the following structures:
Superior vena cava _________________________________________________________
Inferior vena cava _________________________________________________________
5. Describe the direction of blood flow through the right side of the heart. Include the names of all blood
vessels leading into and out of the right side as well as valves involved in blood flow. Indicate which
chambers are in systole and diastole.
6. Describe the direction of blood flow through the left side of the heart in the same way as above.
7. Your heart ejects or pumps about 70 ml of blood into the aorta each time it undergoes systole.
(a) How many times in one minute does your heart pump (beat)? ________________________
(b) Calculate the amount of blood pumped by your heart in one minute (show work).
8. (a) Assume that the bi- and tricuspid valves were closed during diastole. What would happen to blood
movement? ________________________________________________________
_______________________________________________________________________
(b) Assume that the semilunar valves were closed during systole. What would happen to blood
movement? _______________________________________________________________
_______________________________________________________________________
9. In Part D, what body part was represented by the:
(a) Plastic bottle? __________________________________________________________
(b) Water in the bottle? _____________________________________________________
(c) Plastic tube? ___________________________________________________________
(d) Glass tube? ____________________________________________________________
10. A student observes the following cross section slices of blood vessels under a microscope:
A
(a) Which vessel is probably an artery? Why?
(b) Which vessel is probably a vein? Why?