Download Student Background Information 1C

Slicin’ and Dicin’
Activity Introduction:
Student Activity Page 1C
Did you know that every time you breathe, cough, sneeze, or hiccup, you
are using your lungs? The lungs are one of the body’s major organs and are the
main part of the respiratory system. This system allows breathing to happen
about twelve times a minute. We breathe in order to take oxygen into our bodies and get rid
of carbon dioxide. Slicin’ and Dicin’ will allow you to see the inside of the lungs and discover the parts that cause this gas exchange to happen. Instead of a scalpel, dissecting tray, and
pins; get out your colored pencils, scissors, and scientific thinking skills because this dissection is one done on paper and requires your ingenuity in making it layer up!!!
Activity Background:
For this activity, the thoracic cavity has been separated into ten layers: vertebra and ribs,
mediastinum and diaphragm, back (posterior ) lungs, bronchi, alveoli, pulmonary arteries,
pulmonary veins, heart, front (anterior) lungs and ribs and sternum. Each layer
has many unique structures and functions for students to explore. One the
most important ways to expose students to organ structure is through
dissection. In an actual tissue dissection of the lungs, attempts would be
made to see the following parts: pleura, lung lobes, bronchi and respiratory
tree, pulmonary arteries, pulmonary veins, and alveoli. It should be noted,
however, that these details are often difficult for beginners because of the
detail that is lost when preserving lung tissue. Diagrams are included in this activity
so that a paper dissection, with no loss of detail, can be undertaken. The
rationale for using a paper dissection is threefold. One, preserved lungs
are very costly. Two, much of the detail of the dissection is lost in preserved lungs. Three, dissecting fresh lungs can be harmful because of
cross-over pathogens.
Positively Aging®/M. O. R. E.
2007©The University of Texas Health Science Center at San Antonio
Pulmo-Park
The lungs, located in the thoracic cavity, are the primary organs of the
respiratory system. They allow air to move into the body during inspiration and then out
during exhalation. Lungs are made up of millions of tiny alveoli that expand as they fill with
air and become smaller as air leaves. Capillary nets surrounding the alveoli allow oxygen
and carbon dioxide exchange in the red blood cells. During this gas exchange, oxygen-poor
blood loses carbon dioxide into the alveoli and picks up oxygen to carry to cells in the body.
The oxygen-rich blood then provides oxygen to body cells and picks up carbon dioxide to
take back to the lungs. See Figure 1.
LESSON 1
ACTIVITY 1C
26
Alveolar duct opens to
bronchioles.
INHALATION
Oxygen carried to all
parts of the body
by blood.
.ASAL#AVITY
/ /XYGEN
"RONCHIOLE
)NHALED
4O(EART
4RACHEA
"RONCHI
/
)NHALED
2ED
"LOOD
#ELLS
/
/
/
)NHALED
#APILLARY
!LVEOLAR$UCT
#HEST#AVITY
&ROM
(EART
!LVEOLI
2IB#AGE
#/
%XHALED
#APILLARY
"RONCHIOLES
$IAPHRAGM
CO2 from all parts of
body carried to the alveoli
by the blood so it can be
eliminated upon exhaling.
#/
%XHALED
#APILLARY
#/ 2ED"LOOD#ELLS
EXHALATION
Figure 1 Gas Exchange
Figure 2 Anatomy of Respiratory System
Positively Aging®/M. O. R. E.
2007©The University of Texas Health Science Center at San Antonio
Pulmo-Park
Air comes into the body through the nose and mouth and travels down the respiratory tree
into both lungs as shown in Figure 2.
LESSON 1
ACTIVITY 1C
27
The circulatory system works very closely with the respiratory system to provide
body cells with needed oxygen and to remove carbon dioxide waste. The heart
pumps oxygen-poor blood from the body to the lungs through the pulmonary
arteries. Gas exchange occurs in the capillary net surrounding the alveoli.
The newly oxygenated blood then enters the heart through the pulmonary
veins. (Note: The pulmonary arteries carry deoxygenated blood while other
arteries in the body carry oxygen-rich blood. The pulmonary veins carry oxygen
rich blood while other veins in the body carry oxygen poor blood).
A strong muscle, called the diaphragm, contracts and relaxes, helping cause inhalation and
exhalation. This muscle is located beneath the lungs, forming a “floor” for the thoracic cavity.
When the diaphragm contracts, the rib cage expands outward, and air is pulled into the
lungs. Air moves into the lungs, in part, because the extra space created in the chest cavity
creates a lower pressure around the lungs. See Figure3.
Figure 3 Inhalation and Exhalation
Positively
O. R. E.
2007©The University of Texas Health Science Center at San Antonio
Aging®/M.
Pulmo-Park
When the diaphragm relaxes and the ribs are pulled in, greater pressure is created around
the lungs and air moves out. The lungs are incased in a sac known as the pleura sac that
helps maintain the pressure in the lungs. See the Layers of the Lungs Appendix for more
information. The small, balloon-like alveoli are elastic in nature. Because of this elasticity, it
takes effort to inflate the alveoli during inspiration (as in blowing up a balloon), but the
elastic recoil of the alveoli actually helps during exhalation. The first breath taken by
a newborn baby is very difficult because all of the alveoli must be inflated at once
from a completely collapsed state.
LESSON 1
ACTIVITY 1C
28
Activity Materials:
•
•
•
•
•
•
1 Copy of Student Data Page (per student)
1 Copy of Student Activity Page (per group)
1 Copy of “Layers of the Lungs” (per group)
Colored Pencils
Scissors
Extension: 1 copy of Group Assignment Sheet This Layer is Yours! and
It’s All Inside.
Computers, slideshow or moviemaker software, or poster board for creating
showcase; items for creating models (Styrofoam, paints, paintbrushes, chenille sticks,
modeling clay, etc.)
Activity Procedure: Read each step below and check of after it is completed.
p 1.
p 2.
p 3.
p 4.
p 5.
p 6.
p 7.
Secure your group copy of the “Layers of the Lungs”. Assign equal parts of the
activity to each group member.
Color and then cut out each lung layer.
Align at the colored squares, triangles, circles, stars and diamonds as the model
is assembled.
Observing carefully, attempt to arrange the lung layers in the correct order. Each part
of the respiratory system is designed for the specific job it does and you can often
guess what the job is by observing – you will be surprised at what you can do when
you take time to observe and think about what you see!
When you think you have the correct arrangement, raise your hand and ask
your teacher to check your work.
Once your arrangement is checked and approved, make your predictions about
how the layers work together and about the job of each part. Use the graphic
organizer on the Student Data Page and be sure to include information about:
a. What happens to each layer as we breathe?
b. Why is the layer made this way?
c. How does this layer affect other layers?
d. What things can interfere with the process occurring in this layer?
e. What other observations can be made?
When you have completed your information, you will work together as a class with
your teacher to complete the Word Experience Chart included with your Student Data
Page and to “Process Out” the activity.
Extend the activity:
p 8.
p 9.
Divide into groups and draw a topic for further research.
2007©The University of Texas Health Science Center at San Antonio
Pulmo-Park
Use the graphic organizer “It’s All Inside”, found behind the Student Data Page,
to guide your research.
p 10. Make a poster, slideshow, or movie to showcase your findings.
p 11. Create a 3-D craft foam model of your assigned layer. Be creative but remember
that your creativity should be functionally accurate. For instance, the 3-D craft
foam model should have distinguishing details; the alveoli could be represented with seed pearls or cotton balls; pulmonary veins and arteries could
be better represented with red and blue tubing; etc).
LESSON 1
ACTIVITY 1C
Positively Aging®/M. O. R. E.
29