Transcript Function of Respiration

Function of Respiration
SBI3U
RESPIRATORY SYSTEM
• PRIMARY function: BREATHING (for gas
exchange):
1. uptake oxygen needed by the cells
2. release carbon dioxide produced by the cells
(remove waste, pH balance of blood)
• Also used to produce SOUND
Why do we need to breath oxygen? Think
of your previous digestive unit!
cellular respiration:
glucose + oxygen = carbon dioxide and water
HUMAN ADAPTATIONS
• For efficient gas exchange to occur:
1. Water must be present at the respiratory
surface.
Adaptation:
Human lung located within the body cavity
which contains a lot of water and air is
moistened when it enters lungs.
(Compare this to worm, fish, frog, insect…)
Types of respiration in animals
Types of respiration in animals
• Outer skin
– Earthworm
• Gills
– Fish
• Treacheal System
– Insects
• Lungs
– Land animals
http://www.youtube.com/watch?v=HV60yTvy3Mk
http://www.youtube.com/watch?v=XEIRlw5rCUk
Why is this scenario physiologically
impossible?
HUMAN ADAPTATIONS
2. The respiratory surface must be large
Adaptation:
Spread out on a flat surface the gasexchange surface is how big?
a) Half of a basketball court
b) Half of a tennis court
c) Ping pong table
The Human Respiratory System
Nasal cavity
Path taken by air
Path taken by food
The Human Respiratory System
Part
Function
Nasal
Point of entry
passages Filter, warm,
moisten air
Oral
Cavity
Special Features
Mucus, hairs,
many capillaries,
sinus cavities,
turbinates
Warm and moisten Alternate space
air
for gas exchange,
no filtration
The Human Respiratory System
Nasal Cavity
Path taken by air
Path taken by food
Pharynx
Epiglottis
Esophagus
The Human Respiratory System
Part
Pharynx
Function
connects nasal and oral
cavity to larynx
Epiglottis A flap that prevents food
from entering the lungs by
blocking the glottis (opening
of trachea)
Special Features
Cilia in top portion
move food
towards mouth to
be swallowed
Small, flexible
The Human Respiratory System
Larynx
Nasal Cavity
Path taken by air
Path taken by food
Pharynx
Epiglottis
Esophagus
Trachea
Upper
Respiratory
Tract
The Human Respiratory System
Part
Function
Special
Features
Larynx
Contains the vocal
cords – for sound,
“voice box”
“Adam’s Apple”
two flaps of
cartilage, vibrate
when air passes
through
Trachea Passage of air into 2
bronchi, “windpipe”
filter particles up to
mouth
~12cm long
-Semicircular
cartilage rings to
prevent collapse Cilia and mucus
The Human Respiratory System
Larynx
Nasal Cavity
Path taken by air
Path taken by food
Pharynx
Epiglottis
Esophagus
Trachea
Bronchi
Bronchioles
Upper
Respiratory
Tract
The Human Respiratory System
Part
Bronchus
Function
Each carries air into lungs
and splits into many
bronchioles
Bronchiole Many branches carry air to
alveoli
Able to change diameter
to regulate air flow
Special Features
Full cartilage rings
for support
Many branched
tubes, Smallest
passageways, to
increase surface
area
Smooth muscle
walls
NO cartilage rings
The Human Respiratory System
Larynx
Nasal Cavity
Path taken by air
Upper
Path taken by food Respiratory
Pharynx
Tract
Epiglottis
Esophagus
Trachea
Bronchi
Bronchioles
Lower
Respiratory
Alveoli
Tract
Diaphragm
The Human Respiratory System
Part
Function
Special
Features
Alveoli
(singular:
alveolus)
Site of external
respiration (gas exchange)
~150 million very thin tiny
sacs (large surface area)
Single cell layer
thick, surrounded
by capillaries
Coated with
“surfactant” (a
lipoprotein) to
prevent sticking
Diaphragm Increases and decreases
volume of chest cavity
Dome shaped,
thin, muscular
The Human Respiratory System
Part
Function
Pleural
Membrane
Surrounds
lungs and
lines chest
cavity,
reduces
friction
Special
Features
Filled with
fluid that
reduces
friction during
inhalation