11.1 the function of respiration sbi 3u1. what is the function of the respiratory system? to that...
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11.1 The Function of Respiration
SBI 3U1
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….
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
RECALL: GAS EXCHANGE
BREATHING: Inhalation & Exhalation
Inspiration (breathing in, inhaling)Expiration (breathing out, exhaling)
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)
INTERNAL RESPIRATION: Gas Exchange
Exchange of O2 and CO2 between blood and body’s tissue cells ( from blood-> somatic cells)
CELLULAR RESPIRATION–Occurs in the
mitochondria of cells
–Uses O2 and glucose to produce CO2 oxide and water
–Produces energy ( ATP)
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
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)
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
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
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
*Note: Inhalation- diaphragm contracts and moves down
Exhalation-Diaphragm relaxes and moves up
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.
Measuring Respiratory VolumeUNIT 4 Chapter 11: The Respiratory System Section 11.1
Spirographs represent the amount of air that moves into and out of the lungs with each breath as measured by a spirometer.
Spirographs
UNIT 4 Chapter 11: The Respiratory System Section 11.1
Homework:
Read and make notes 11.1 Complete pg. 444 #1-6 and pg. 447 #9-11