Do Now
 Matching Quiz!
 Peer Corrections
Homework Due Today
 Read 33.3 – The Respiratory System
 Define
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Larynx
Pharynx
Trachea
Diaphragm
Homework Review
 Larynx
 Contains 2 highly elastic folds of tissue known as the vocal cords
 Pharynx
 Cavity at the back of the mouth in which air passes
 Trachea
 Windpipe
 Diaphragm
 At the bottom of the chest cavity; large dome-shaped muscle
responsible for creating ‘negative pressure’ to allow for
respiration
Homework Due Friday
 Read 35.1
 Answer questions 1a, 1b, 2a on page 1013
Respiratory System
 What does it do?
 Picks up oxygen from air we inhale
 Release Carbon Dioxide (CO2) in the air we exhale
Respiratory System
Structures
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Nose
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Pharynx
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Larynx
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Trachea
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Lungs
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Bronchus
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Bronchioles
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Alveoli
Gas Exchange
 What gases need to be “exchanged”?
 Alveoli – End of air flow
 Oxygen dissolves into moisture, then diffuses across
capillary walls into blood
 Diffuses across because the oxygen concentration is less
inside the blood
 CO2 diffuses into alveoli from capillaries because the
concentration of CO2 is less in the alveoli
Gas Exchange
 Respiratory System & Gas Exchange
Flowchart Exercise!
 Using the given words, create a flowchart to show the
passage of oxygen into the blood stream
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Bronchioles
Larynx
Nose
Alveoli
Pharynx
Bronchus
Capillary
Trachea
Diffusion
 Moving from high concentration to low concentration
 100 people in Athletic Office
 “Passive Process”
 Diffusion of oxygen occurs until concentrations are the
same
 Hemoglobin binds to dissolved oxygen, removing it
from plasma, allowing for more diffusion
 60 times more!
Breathing
 Majority of breathing is voluntary
 However, whether conscious or unconscious, nervous
system has the ‘final say’
 Medulla oblongata
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Helps the body function when unconscious
Breathing
BP
Heart rate
Smoking & Respiratory
System
 3 most dangerous substances
 Nicotine
 Carbon Monoxide
 Tar
Smoking
 Nicotine
 Addictive stimulant
 Increases HR and BP
 Carbon Monoxide (CO)
 Poisonous gas
 Blocks hemoglobin from binding with oxygen
 Tar
 Contains at least 60 compounds known to cause cancer
Homework Due Friday
 Read 35.1
 Answer questions 1a, 1b, 2a on page 1013