1. 11.1 The Function of Respiration
SBI 3U1

2. What is the function of the Respiratory System?
To that ensure that oxygen is brought in and carbon dioxide is removed from each cell in the body….

3. The 4 stages of Respiration:
1) Breathing- inspiration/inhalation and expiration/exhalation
2) External Respiration- exchange of gases between lungs and blood
3) Internal Respiration- exchange of gases between blood and cells
4) Cellular Respiration- energy-releasing reactions inside the cells

4. RECALL: GAS EXCHANGE

5. BREATHING: Inhalation & Exhalation
Inspiration (breathing in, inhaling)
Expiration (breathing out, exhaling)

6. EXTERNAL RESPIRATION: Gas Exchange
Exchange of O2 and CO2 between the inspired air in the lungs and the blood (from the alveoli to the capillaries)

7. INTERNAL RESPIRATION: Gas Exchange
Exchange of O2 and CO2 between blood and body’s tissue cells ( from blood-> somatic cells)

8. CELLULAR RESPIRATION Occurs in the mitochondria of cells
Uses O2 and glucose to produce CO2 oxide and water
Produces energy
( ATP)

9. Respiratory Surfaces
There are 2 requirements for respiratory surfaces:
1) They must be large enough for gas exchange to occur quickly enough to meet the body’s needs.
2) They must be moist so gases can dissolve

10. Types of Respiratory Surfaces in Animals
1)Outer Skin
entire outer skin is used
diffusion transports O2 and CO2 in and out of cells from blood
organism must live in moist environments (ie. Worms)
2)Gills
extensions of folds in the body surface that increase surface area
diffusion transports gases to blood and cells
organisms live in aquatic environments (ie. Fish)

11. Types of Respiratory Surfaces in Animals cont’d…
3)Tracheal System
Ie. insects
internal system of branching respiratory tracheae (tubes)
tracheae connect cells directly to environment for gas exchange (blood not required)
4)Lungs
Ie. large animals/ humans
lungs contain sacs lined with a moist surface (epithelium); these sacs increase surface area
blood transports gases to cells by diffusion

12. The Mechanisms of Breathing
Brain
co-ordinates breathing movements
Monitors volume of air in the lungs/gas in the blood
Diaphragm and Rib Muscles
Control air pressure in lungs

14. Air Pressure in the Lungs
Inspiration (inhalation)
intercostal muscles and the diaphragm contract
the rib cage moves up and out
the volume increases, the pressure inside the lungs decreases.
Expiration (exhalation)
The diaphragm and intercostal muscles relax
The rib cage moves down and inward
volume decreases, pressure inside the lungs increases

15. *Note:
Inhalation- diaphragm contracts and moves down
Exhalation-
Diaphragm relaxes and moves up

16. Measuring Respiratory Volume
UNIT 4
Chapter 11: The Respiratory System
Section 11.1
Measuring Respiratory Volume
Tidal volume-the volume of air that is inhaled and exhaled in a normal breathing movement (taken when body is at rest).
Inspiratory reserve volume -the additional volume of air that can be taken into the lungs beyond a regular (tidal) inhalation.
Expiratory reserve volume- the additional volume of air that can be forced out of the lungs beyond a regular (tidal) exhalation.
Vital capacity (total lung volume) -the total volume of gas that can be moved into or out of the lungs.
tidal volume + inspiratory reserve volume + expiratory reserve volume = vital capacity
Residual volume -the amount of air that remains in the lungs and passageways even after a full exhalation.

17. UNIT 4
Chapter 11: The Respiratory System
Section 11.1
Spirographs
Spirographs represent the amount of air that moves into and out of the lungs with each breath as measured by a spirometer.

18. Homework:
Read and make notes 11.1 Complete pg. 444 #1-6 and pg. 447 #9-11