2. When you breathe in or inhale , the
diaphragm muscle contracts. Inhaling
moves the diaphragm down and
expands the chest cavity.
Simultaneously, the ribs move up and
increase the size of the chest cavity.
There is now more space and less air
pressure inside the lungs. Air pushes in
from the outside where there is a higher
air pressure.
3. It pushes into the lungs where there is a
lower air pressure. When you breathe
out, or exhale, the diaphragm muscle
relaxes. The diaphragm and ribs return
to their original place. The chest cavity
returns to its original size. There is now
less space and greater air pressure
inside the lungs. It pushes the air
outside where there is lower air
pressure.
4.
5. Why do we believe that life is
possible only on planets where
oxygen is present?
Oxygen is necessary for life to exist.
Without it, the cells in the body would
not be able to release the energy in
food for power, and they would die
within minutes. When you inhale air,
your respiratory system gets oxygen.
When you exhale, carbon dioxide is
released.
7. Objectives:
- Describe blood flow and gas
exchange within the heart,
circulatory system, and lungs
- Explain the mechanism of how the
respiratory and circulatory systems
work together
9. Procedure:
1. Perform the activity with your group
mates (5 persons).
2. Assign and label different areas in
the outdoor setting as:
lungs, left atrium, left ventricle,
arteries, capillary, veins, right ventricle,
and right atrium.
10. 3. Using the marking pen, write down
the word oxygen (Red) on as many
paper strips as you can and place them
in the lung area. The capillary area
should have papers with carbon
dioxide (Blue) written on them.
4. Use the chalk to mark and define the
different areas such as what is given in
the diagram below. Assign some
members of your group to stand still on
the different marked areas.
11.
12. 5. Choose two members from the group to
take the trip around the different posts. Let
the partners start the tour in the lung area
and together pick up a paper labeled as
oxygen from another member standing at
his post. They should carry the strip of
paper to the heart, passing through the left
atrium, and then to the left ventricle. As the
partners go to every station, they must leave
a trail of rope or ribbon held by another
member in a designated area, until the path
of the journey is completely traced.
13. 6. Partners must run along the
chalk marks representing the
arteries into the capillary area.
7. Tell the partners to exchange
the strip of paper representing
oxygen for a piece of paper
representing carbon dioxide with a
member in his designated area.
14. 8. Make the partners run along the chalk
marks representing the veins into the
heart area, first to the right ventricle,
then to the right atrium.
9. The partners must then run back into
the lung area where the process begins
again. When there are no more strips of
paper, the activity is over. The leader
may want to keep placing new papers
into designated areas to keep the game
going on longer.
15. Guide Questions:
Q1. How do the heart and the lungs work
together?
Q2. What takes place when you inhale and
exhale?
Q3. What does blood deliver to every part
of the body?
Q4. Why is oxygen important to your
body?
Q5. How will you describe the sequence of
oxygen, carbon dioxide, and blood flow in
your own words?
16.
17. The human respiratory system
functions for the exchange of oxygen
and carbon dioxide. Every breath you
take allows air to enter your body
through the nose down to the lungs,
where gas exchange takes place. The
human respiratory system comprises
the nose, pharynx, larynx, trachea,
bronchi and both lungs.
18.
19. Note that in the figure bronchi branches
into smaller tubes called bronchioles,
ending up in air sacs called alveoli.
20. When you inhale, the air you breathe
moves through your nose and nostrils
to a tube at the back of your mouth. This
tube is called pharynx or layman’s term,
the throat. The pharynx serves as the
passageway for air and food. Air travels
from the pharynx to the trachea, also
known as windpipe.
21. The epiglottis is a cartilage that covers
the entrance to the trachea when you
swallow. This part prevents food from
going into your lungs. The respiratory tract
allows air to pass straight into your body
tissues through the lungs .
22. Above the trachea is the larynx, which
has two elastic tissue folds called vocal
chords. When muscles pull the vocal
chords together, the air that moves
between them creates vibration and
sound. So every time you speak, sing
whisper, or shout you know where your
voice comes from.
23. Air continues its journey from the larynx
to the trachea and then to the two
bronchi in the thoracic or chest cavity.
The left and right bronchi both lead to the
lungs. In the lungs, the bronchi
subdivides into bronchioles. The
bronchioles finally end in small, moist
sacs called alveoli. The alveoli. The
alveoli resemble bunches or clusters of
grapes. This is where gas exchange
takes place.
24. A healthy lungs contains more than three
million alveoli, which account for the large
surface area available for gas exchange.
Inhaled oxygen dissolves on the surface of
the alveoli and diffuses across the capillary
network where it enters the blood. On the
other hand, carbon dioxide (CO2) is a
waste product in the bloodstream. CO2
diffuses in the opposite direction. It travels
across an alveolar membrane and into the
air to be exhaled.
