Download B20 C7.1 Notes The Respiratory System

B20 C7 The Respiratory System p. 242
The respiratory system provides O2 from the air for delivery to the cells and removes waste
CO2 from our bodies.
 Check out this link https://www.youtubefilter.com/watch?v=hc1YtXc_84A
 Fill out BLM 7.1.2 The Human Respiratory System (p. 245 – 248)
 Draw and label the respiratory tract on your “Respiration Person”
Respiration has 4 stages
(7.1)
1) Inspiration (inhaling) and expiration (exhaling) exchanges air between the environment
and the lungs.
2) External respiration exchanges O2 and CO2 between the air in the lungs and our blood.
3) Internal respiration exchanges O2 and CO2 between the blood and the cells of our body’s
tissues.
4) Cellular respiration is the final step in the respiratory system – O2 is provided to the cells
to breakdown glucose for energy (ATP) for life, and CO2 is the waste product.
Air moves into the lungs through the upper and lower respiratory tract: air is
cleaned, moistened, and warmed, and the respiratory tract provides a huge
surface area for gas exchange.
Air is cleaned, moistened and warmed as it moves into the lungs through the upper and lower
respiratory tract. Respiration needs a moist environment. The O2 in the lungs and the waste CO2
must be dissolved in H2O for diffusion of these gases between the lungs and our blood to take
place.
• Cilia, small hairs lining the nasal passages and the
respiratory tract, clean the air by filtering out dust
and their particles and by beating (waving back and
forth) can move the dirty particles out..
• Mucus also cleans the air by trapping unwanted
particles in the air. These dirty particles are then
expelled by the cilia, or we cough or blow the mucus
out. Mucus also moistens the air.
• Blood vessels in the nasal passages and our
internal body temperature warms the air.
1) The upper respiratory tract:
Nostrils nasal passages  pharynx (throat) larynx (voicebox)  trachea (windpipe)
2) The lower respiratory tract: 2 bronchi bronchioles  alveoli
Continues to clean, moisten and warm air entering the lungs.
The alveoli (clusters of tiny sacs at the end of each bronchiole) are the site of O2 and CO2
exchange. Fresh O2 diffuses across the alveoli membranes into the capillaries of the
circulatory system, enters the heart and is pumped to the rest of the body. Waste CO2
diffuses from the capillaries into the alveoli for exhalation.
The highly branching bronchi/bronchiole system and clusters of alveoli provide greatly
increased surface area to exchange O2 and CO2 fast enough to meet the body’s needs.
The branching bronchi/bronchiole system
 Learning Checks!
1) What is the main function of the respiratory system?
2) How is external respiration different from internal respiration?
3) What is the job of cilia? Mucus? The cartilaginous rings in the trachea and
bronchi?
4) What is the upper repiratory tract? The lower respiratory tract?
5) Why is “bronchial tree” a good metaphor for the bronchi and bronchioles?
6) #12 and 13 pg. 248.
7) What are 2 characteristics of the alveoli that make them efficient for gas
exchange in terms of surface area?
 Draw and label the respiratory tract on your “Respiration Person”