1. 37-3 The Respiratory System
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2. The Human Respiratory System
The respiratory system consists of the:
Epiglottis
Trachea
Nose
Pharynx
Larynx
Lungs
Bronchus
Mouth
Diaphragm
Bronchioles
The respiratory system is responsible for the exchange of oxygen and carbon dioxide. Air moves through the nose, pharynx, larynx, trachea, and lungs. After reaching the lungs, the trachea branches into smaller and smaller tubes called bronchioles, which end in alveoli, or air sacs.
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What Is Respiration?
What Is Respiration?
In biology, respiration means different things.
Cellular respiration is the release of energy from the breakdown of food in the presence of oxygen (occurs in which organelle?)
At the organism level, respiration is the process of gas exchange—the release of carbon dioxide and the uptake of oxygen that occurs between RBCs and alveoli
Breathing is the actual mechanical intake of air
MITOCHONDRIA
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Breathing
BREATHING
Lungs are sealed in pleural membranes inside the chest cavity.
At the bottom of the cavity is a large, flat muscle known as the diaphragm.
Pleural cavities are like big plastic bag around the lungs.
During inhalation the rib cage rises and the diaphragm contracts, increasing the size of the chest cavity.
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Breathing
During inhalation, the diaphragm contracts and the rib cage rises up.
This expands the volume of the chest cavity.
The chest cavity is sealed, so this creates a partial vacuum inside the cavity.
Atmospheric pressure fills the lungs as air rushes into the breathing passages.
During inhalation the rib cage rises and the diaphragm contracts, increasing the size of the chest cavity.
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Everyone take a deep breath and hold it. That is INHALATION Your rib cage and diaphragm expand.
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Breathing
Often exhaling is a passive event.
When the rib cage lowers and the diaphragm relaxes, pressure in the chest cavity is greater than atmospheric pressure.
Air is pushed out of the lungs.
Air Exhaled
Rib cage lowers
During inhalation the rib cage rises and the diaphragm contracts, increasing the size of the chest cavity.
Exhalation
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9. How Breathing Is Controlled
Breathing is controlled by the medulla oblongata.
The medulla oblongata monitors carbon dioxide in the blood.
As carbon dioxide increases, nerve impulses make the diaphragm contract, bringing air into the lungs.
The higher the carbon dioxide level, the stronger the impulses.
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So what’s a hiccup?
A hiccup is a muscle spasm of the diaphragm.
Guinness medical record breakers. Longest attack ofhiccups. Charles Osborne ( ) of Anthon, Iowa, the US, started hiccupping in 1922 while attempting to weigh a hog before slaughtering it. He was unable to find a cure, and continued hiccupping until February 1990, a total of 68 years.
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11. The Human Respiratory System
RESPIRATION
Alveoli are clusters of tiny sacs at the ends of air passages.
A network of capillaries surrounds each alveolus.
Pulmonary artery
Pulmonary vein
The respiratory system is responsible for the exchange of oxygen and carbon dioxide.
Capillaries
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Gas Exchange
RESPIRATION
Gas exchange takes place in the alveoli.
Oxygen diffuses into the blood.
Carbon dioxide in the blood diffuses out of the blood to the alveolus.
Let’s examine this up close O2
CO2
Gas exchange occurs by diffusion across the membrane of an alveolus and a capillary.
Capillary
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