Respiratory System

BIG IDEA

Circulatory system supplies entire body with oxygenated blood

Respiratory system supplies blood with oxygen• Respiratory Tract• Gas exchange• Breathing

Respiratory Tract

• Nasal (or oral) cavity

• Pharynx• Larynx• Trachea• Bronchi• Bronchiole• Alveoli

Nasal Cavity3 main functions:• Cleans the air • Warms the air• Moistens the air

Pharynx (throat)• The place where the

nasal cavity, esophagus (digestive tract) and trachea (respiratory tract) meet

• Epiglottis is the door that allows food to go down the esophagus (digestive tract) and air down the trachea (respiratory tract)

https://www.cdli.ca/courses/biol2201/unit03_org03_ilo02/8_12_cap.jpg

Larynx (voice box)• Houses the vocal

cords• Vibrations of the

cords produces sound

• Prevent food to go down the trachea

Larynx Cartilages• Soft bone that provide structural support to

Larynx

Trachea (windpipe)• Composed of

cartilage (soft bone)

• Helps maintains rigidity to prevent the respiratory passage from collapsing

Bronchi

Why does Trachea branches into 2 bronchi?

• Bronchi branch into smaller bronchiole eventually ending at the alveoli

Left and Right lung

Bronchi

Alveoli

• Spherical hollow cavities increase surface area

• Walls are only 1 cell thick making it easy for rapid diffusion

Why high surface area is needed?

Alveoli

• Why capillaries are two colored?

• What material is exchanged?

Capillaries line the alveoli for gas exchange

Gas Exchange

Which direction does blood flow?

Alveoli: Gas ExchangeOxygen goes into the blood vessel.

Carbon dioxide (a waste product) leaves the blood vessel into the alveolus.

Respiration Summary

http://www.youtube.com/watch?v=HiT621PrrO0&feature=fvwrel

BreathingProcess• Inhalation: taking air into the lungs• Exhalation: breathing out air

Muscles• Diaphragm (between lung and

stomach)• Ribcage muscles

Ribs & Diaphragm

Ribs

Diaphragm

Ribcage Muscles

Model

Model of Respiration

http://www.breathing.com/images/176/ani-final/intro/lungs-jugs/breathing=sm.gif

Breathing

Breathing

ProcessRibcag

eMuscles

RibCage

Diaphragm Volume

Internal Pressur

eAir

Inhalation

Contract

Expand

(up and out)

Contract(moves down)

FlattensIncrease Decreas

eMoves

in

Exhalation Relax

Reduce

(down and in)

Relax(moves

up)Dome-shaped

Decrease Increase Moves

out

Breathing• Involuntary• Can override system temporarily (e.g.

hold our breath)• Breathing rate determined by amount

of carbon dioxide detected in blood• When carbon dioxide increases,

breathing rate increases, heart beats faster to let in more oxygen