Biology grade 11_respiratory system
Lesson 5: The Function of Respiration
Human Respiratory System
Larynx
Voice box
Contains 2 thin elastic ligaments
Vibrate to produce sound
As air is forced up from lungs through larynx
Muscular tension & position of vocal cords
Produce different sounds
Alveoli
Network of capillary surround each alveoli
Allow for exchange of O2 and CO2
Trachea, Bronchi & Bronchioles
Trachea & Bronchi
Supported by rings of cartilage
Cilia & Mucus (producing goblet cell)
Line inside of trachea, bronchi and bronchioles trap particles such as bacteria, dust and pollen
Human Respiratory System
Air enters nostrils
Tiny hairs & mucus filter dust/foreign particles
Air warmed and moistened in nostrils before moving towards pharynx
(Where nasal & oral cavity join)
Air moves down trachea
Branches into 2 bronchi which divide into network of bronchioles
Bronchioles end w/ small air sacs called alveoli
Gas exchange occurs at alveoli
Respiratory System
Function: gas exchange
Supply O2 and remove CO2 from body
Respiration (entire process)
1) Breathing
2) External Respiration
3) Internal Respiration
4) Cellular Respiration
Stage 1: Breathing
Stage 2: External Respiration
Stage 3: Internal Respiration
Stage 4: Cellular Respiration
Inspiration: Breathing in –air from outside lungs
(diaphragm moves down)
Expiration: Breathing out –air from lungs outside
Gas exchange occurs
O2 & CO2 exchanged b/w air in lungs and blood
Exchange O2 & CO2 b/w blood and cells of body tissues
Series of energy-releasing chemical reactions take place in mitochondria
(ATP = energy molecules)
(Organic molecules = glucose)
2 Main Requirements for Respiration
Respiratory Surface
Must be large enough for gas exchange at rate that meets body’s need
Moist Environment
For dissolving O2 & CO2 in water
Respiratory Surface
area where gas exchange occurs
ALL organisms have ventilation
Human Respiratory System
Larynx
Voice box
Contains 2 thin elastic ligaments
Vibrate to produce sound
As air is forced up from lungs through larynx
Muscular tension & position of vocal cords
Produce different sounds
Alveoli
Network of capillary surround each alveoli
Allow for exchange of O2 and CO2
Trachea, Bronchi & Bronchioles
Trachea & Bronchi
Supported by rings of cartilage
Cilia & Mucus (producing goblet cell)
Line inside of trachea, bronchi and bronchioles trap particles such as bacteria, dust and pollen
Human Respiratory System
Air enters nostrils
Tiny hairs & mucus filter dust/foreign particles
Air warmed and moistened in nostrils before moving towards pharynx
(Where nasal & oral cavity join)
Air moves down trachea
Branches into 2 bronchi which divide into network of bronchioles
Bronchioles end w/ small air sacs called alveoli
Gas exchange occurs at alveoli
Respiratory System
Function: gas exchange
Supply O2 and remove CO2 from body
Respiration (entire process)
1) Breathing
2) External Respiration
3) Internal Respiration
4) Cellular Respiration
Stage 1: Breathing
Stage 2: External Respiration
Stage 3: Internal Respiration
Stage 4: Cellular Respiration
Inspiration: Breathing in –air from outside lungs
(diaphragm moves down)
Expiration: Breathing out –air from lungs outside
Gas exchange occurs
O2 & CO2 exchanged b/w air in lungs and blood
Exchange O2 & CO2 b/w blood and cells of body tissues
Series of energy-releasing chemical reactions take place in mitochondria
(ATP = energy molecules)
(Organic molecules = glucose)
2 Main Requirements for Respiration
Respiratory Surface
Must be large enough for gas exchange at rate that meets body’s need
Moist Environment
For dissolving O2 & CO2 in water
Respiratory Surface
area where gas exchange occurs
ALL organisms have ventilation