Download 15-3 Aim: Respiratory System (A) RESPIRATORY SYSTEM

15-3
Aim: Respiratory System
(A) RESPIRATORY SYSTEM
 The respiratory system involves both external and internal respiration
 External respiration: ___________________________________________
______________________________________________________________
 Internal respiration: ___________________________________________
______________________________________________________________
 _________________________________________: involves the use of
oxygen to break down glucose in the cell
 **The main job of the respiratory system is to _____________________
______________________________________________________________
______________________________________________________________
 The respiratory system is responsible for transporting gases to and from
the circulatory system.
 Respiration is a vital function for all living things. Organisms cannot
live more than a few minutes without oxygen.
 The respiratory system is a _______________________________________

_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
(B) THE PATH OF AIR
 The human respiratory system consists of:
o The nose
o Pharynx
o Larynx
o Trachea
o Smaller passageways
o Lungs
o Alveoli
 The path of air is as follows:
1) Nose: the air enters through the nose—hairs in the nose
____________________________________________________
____________________________________________________
2) From the nose, air passes through the pharynx:
____________________________________________________
______________________________________________________
______________________________________________________
—when food is swallowed, a flap of cartilage called the
___________________________, presses down and covers the
opening to the air passage
3) From the pharynx, the air moves through the larynx:
______________________________________________________
______________________________________________________
______________________________________________________
4) From the larynx, the air passes into the trachea:
______________________________________________________
______________________________________________________
______________________________________________________
5) The trachea, divides into two smaller tubes,
_______________________________: which lead to the lungs
6) Within the lung, the bronchi divide into smaller tubes called
______________________________: continue to subdivide
until they finally end in clusters of tiny hollow air sacs called
alveoli
7) Alveoli:
______________________________________________________
______________________________________________________
______________________________________________________
 The lungs are amongst the largest organs of the body
 Below the lungs is the diaphragm—
______________________________________________________________
______________________________________________________________
______________________________________________________________
(C) BREATHING
 Breathing:
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
 Ventilation:
_______________________________________________________________
_______________________________________________________________
 Every time you take a breath, or move air in and out of your lungs,
TWO major actions take place:
i. ________________________________: aka INSPIRATION—
occurs when air is pulled into the lungs
ii. ________________________________: aka expiration—occurs
when air is pulled out of the lungs
 These two actions deliver oxygen to the alveoli and remove carbon
dioxide
 The continuous cycles of inhalation as exhalation are known as
________________________________________
 These two actions are produced by movements of the diaphragm
 During INHALATION—the diaphragm is curved upward—
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
 During EXHALATION—the diaphragm relaxes and returns to its curved
position—
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
(D) GAS EXCHANGE
 Three important things happen to the air we inhale:
1) ___________________________________________________
2) ___________________________________________________
3) ___________________________________________________
This occurs in the _______________________________ in the lungs
Our lungs consist of nearly 300 million alveoli!!!
Each alveolus is covered with capillaries for gas exchange
The blood entering the alveoli contains a large amount of
__________________________________________________________
 The blood leaving the alveoli has nearly tripled the total amount of
____________________________________________ it originally carried




(E) REGULATION OF BREATHING
 Breathing is such an important function that your nervous system will
not let you have complete control of it.
 TEST IT!! Try holding your breath!!
 Breathing is an involuntary action. This means
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
 You can hold your breath until you lose consciousness, but then the
brain takes control and normal breathing resumes