Download M6 Lesson 7 Respiration - SBI3UAnimalUnit

The Respiratory System
 Basic function: to enable
body cells to be supplied
with oxygen and rid the
body of carbon dioxide.
 Between 17 000 and 29 000 breaths a
day
 Take a deep breath
 You
just captured 3-4L of air in your
lungs!
 Breathing is so important that it
cannot be left to conscious control
Nasal
Cavity
Throat
Nose
(pharynx)
Mouth
Windpipe
(Trachea)
Bronchus
Bronchiole
Alveolus
Diaphragm
Lungs
Ribs
The Passage of Air Through the
Upper Respiratory Tract:
Nostrils/mouth

Nasal passages

Pharynx
(Epiglottis = opening to
trachea)

Enters the trachea

Glottis

Larynx

Continue down the trachea…
Turbinate Bones
 Very thin
 Project into the nasal passages
 Increase the SA of these chambers
 Have a thin membrane that secretes mucus
 Moistens air
 Traps particles (dust, bacteria, foreign matter)
 Ciliated cells found in the membrane move particles into the
nose or throat to be expelled by sneezing of coughing
 Capillaries (in the lining of the turbinates) supply
warm blood to the nasal passages.

Heat air to body temperature to protect delicate structures
in lower respiratory tract from damage by cold air.
Pharynx
 Pharynx (throat) is a
passageway behind the
mouth that connects the
mouth and nasal cavity to
the larynx and esophagus
 Air is then passed down to
your trachea (windpipe)
Glottis
 Opening of the trachea through which air enters the
larynx
 Can be closed by the epiglottis
Larynx
 Made of cartilage (tough, firm connective tissue)
 Used for sound production in mammals - contains
vocal cords

Two folds of membrane stretched across the larynx
 During normal breathing muscular tissue holds vocal
cords apart and air passes freely through
 Sound: cords are moved closer together and pressure
from the air expelled causes them to vibrate



Pitch: varies with length of vocal cords.
Long cord (low sound), shorter cord (higher sound)
*Puberty: male vocal cords grow quickly, often causing a
breaking quality in the voice. This disappears once finished
growing
 Air continues down the trachea after the larynx
Trachea
 A flexible tube that carries air
from nasal passages/mouth 
bronchi and then to lungs
 Held open by semi-circular
rings of cartilage

~10-12 cm long from throat to
middle of chest where it splits
Bronchi  Bronchioles
 Trachea splits up into two bronchi
tubes. These two tubes keep splitting
up and form your bronchioles.
 They get smaller and smaller and end
with small air sacs called
alveoli…
Lungs and Pleura
 Left vs. right lung…?
 Pleural membrane: thin, flexible, double-layered sac
surrounds the lungs
 Outer layer attaches to the inside of the chest wall
 Inner layer covers the lungs
 Thin space between has
lubricating fluid that allows
the layers to slide easily
against each other during
breathing
Alveoli
 Alveoli: these tiny air sacs =
site of gas exchange
 Capillaries surround them
 Walls and capillaries are only
one-cell thick!
 O2 and CO2 diffuse through,
traveling into/out of blood
stream
 ~500 million in an average
adult human lung
Gas Exchange at the Alveoli
HOW TO WRITE A LAB REPORT
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Title Page (Title, name, date etc.)
Purpose and Introduction
Hypothesis
Materials
Procedure
Observations/Results (tables and graphs here)
Discussion
Conclusions
Answers to Textbook Questions (pg. 447 #1-4)
References
Measuring Respiratory Volume Lab
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Investigate your respiratory volume using a
spirometer provided
Follow procedure on pg. 447
Record your observations
Discuss why you observed what you did with your
partner
Upload your respiratory volumes to the class wiki
before the end of tomorrow’s class – we will
generate a class graph to include in your lab report
Write up your formal lab report due Friday March
9th (or Tuesday by email… [email protected])