ppt on the respiratory system mechanishm in humans and the parts of the human respiratory system

1. The Respiratory
System
Made by-
Vaishnav Sethumadhavan
10-A

2. Respiration Includes
• Pulmonary ventilation
– Air moves in and out of lungs
– Continuous replacement of gases in alveoli (air sacs)
• External respiration
– Gas exchange between blood and air at alveoli
– O2 (oxygen) in air diffuses into blood
– CO2 (carbon dioxide) in blood diffuses into air
• Transport of respiratory gases
– Between the lungs and the cells of the body
– Performed by the cardiovascular system
– Blood is the transporting fluid
• Internal respiration
– Gas exchange in capillaries between blood and tissue cells
– O2 in blood diffuses into tissues
– CO2 waste in tissues diffuses into blood
– The respiratory system is made of 7 parts, the larynx, trachea, alveolus,
bronchus, bronchioles, lungs and the diaphragm
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3. Nose
• Provides airway
• Moistens and warms
air
• Filters air
• Resonating chamber
for speech
• Olfactory receptors
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External nose

4. The Pharynx (throat)
• 3 parts: naso-, oro- and laryngopharynx
• Houses tonsils (they respond to inhaled antigens)
• Uvula closes off nasopharynx during swallowing so food
doesn’t go into nose
• Epiglottis posterior to the tongue: keeps food out of airway
• Oropharynx and laryngopharynx serve as common
passageway for food and air
It is lined with stratified squamous epithelium for protection
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5. The Larynx (voice box)
– It Produces vocalizations (speech)
– It Provides an open airway (breathing)
– Switching mechanism to route air and food into proper
channels
• Closed during swallowing
• Open during breathing
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6. Trachea (the windpipe)
• Divides in thorax into two
main (primary) bronchi
• 16-20 C-shaped rings
of hyaline cartilage
joined by fibro elastic
connective tissue
• Flexible for bending
but stays open despite
pressure changes
during breathing
• Connects mouth and
nose to lungs 6

7. Respiratory Zone
• End-point of respiratory tree
• Structures that contain air-exchange chambers are called alveoli
• Respiratory bronchioles lead into alveolar ducts: walls consist of alveoli
• Ducts lead into terminal clusters called alveolar sacs – are microscopic chambers
• There are 3 million alveoli!
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8. Gas Exchange
• Air filled alveoli account for most of the lung volume
• Very great area for gas exchange (1500 sq ft)
• Alveolar wall
• Single layer of squamous epithelial cells.
• External wall covered by cobweb of capillaries
• It has air on one side and blood on the other. This “air-blood barrier” is
where gas exchange occurs
– Oxygen diffuses from air in alveolus (singular of alveoli) to blood in capillary
• Carbon dioxide diffuses from the blood in the capillary into the air in the
alveolus
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9. Lungs
• Each is cone-shaped with anterior, lateral and
posterior surfaces contacting ribs
• Superior tip is apex, just deep to clavicle
• Concave inferior surface resting on diaphragm is
the base
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apex apex
base base

10. INSPIRATION AND EXPIRATION
INSPIRATION
During inspiration, the dome
shaped diaphragm
flattens as it contracts
and the external
intercostal muscles
contract to raise the ribs
EXPIRATION
During expiration Inspiratory
muscles relax so the rib
cage drops under force of
gravity and the relaxing
diaphragm moves up. Due
to this the air is forced out.

11. Respiratory system in fishes
Oxygen and carbon dioxide dissolve in water, and most fishes
exchange dissolved oxygen and carbon dioxide in water by means
of the gills. The gills lie behind and to the side of the mouth cavity
and consist of fleshy filaments supported by the gill arches and filled
with blood vessels, which give gills a bright red colour. Water taken
in continuously through the mouth passes backward between the gill
bars and over the gill filaments, where the exchange of gases takes
place. The gills are protected by a gill cover in teleosts and many
other fishes but by flaps of skin in sharks, rays, and some of the
older fossil fish groups. The blood capillaries in the gill filaments are
close to the gill surface to take up oxygen from the water and to give
up excess carbon dioxide to the water.
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12. How to keep your respiratory
system healthy
• Avoid:
-Smoking
-Being around a smoker(SecondHand)
-Inhaling other chemicals and drugs.
-Being around dusty or thick polluted air.
• What to do:
- Exercise
- Eat healthy
- Go to annual doctor checkups

13. Interesting Facts About the
Respiratory System!!
• About half a liter of water per day is lost through
breathing.
• Yawning brings more oxygen to the lungs.
• Your right lung is larger than your left.
• We breathe 13 pints of air every minute.
• People under 30 take in double the amount f
oxygen in comparison to someone who's 80
years old.

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