Download Check your Wellness The respiratory system carries oxygen into the

Chapter 16
Respiratory Health
Pages 363 – 369
Introduction: Check your Wellness
The respiratory system carries oxygen into the bloodstream and removes carbon dioxide from it.
The circulatory system brings oxygen, nutrients, and other materials to body cells and carries
waste from them. The two systems work together to deliver oxygen to cells and remove cellular
waste from the body.
Oxygen Delivery System
The primary function of the respiratory system is to supply the blood with oxygen in order for the blood to deliver
oxygen to all parts of the body. The respiratory system does this through breathing. When we breathe, we inhale
oxygen and exhale carbon dioxide. This exchange of gases is the respiratory system's means of getting oxygen to the
blood.
Respiration is achieved through the mouth, nose, trachea, lungs, and diaphragm. Oxygen enters the respiratory
system through the mouth and the nose. The oxygen then passes through the larynx (where speech sounds are
produced) and the trachea, which is a tube that enters the chest cavity. In the chest cavity, the trachea splits into two
smaller tubes called the bronchi. Each bronchus then divides again forming the bronchial tubes. The bronchial tubes
lead directly into the lungs where they divide into many smaller tubes, which connect to tiny sacs called alveoli. The
average adult's lungs contain about 600 million of these spongy, air-filled sacs that are surrounded by capillaries. The
inhaled oxygen passes into the alveoli and then diffuses through the capillaries into the arterial blood. Meanwhile, the
waste-rich blood from the veins releases its carbon dioxide into the alveoli. The carbon dioxide follows the same path
out of the lungs when you exhale.
The diaphragm's job is to help pump the carbon dioxide out of the lungs and pull the oxygen into the lungs. The
diaphragm is a sheet of muscles that lies across the bottom of the chest cavity. As the diaphragm contracts and relaxes,
breathing takes place. When the diaphragm contracts, oxygen is pulled into the lungs. When the diaphragm relaxes,
carbon dioxide is pumped out of the lungs.
The pathway of air: Nose, mouth, and throat
How does the air get into your lungs?
Air passes through your nose or mouth and down the throat into the bronchi tubes
so the air can enter the lungs
In the Nose:
•
Air is warmed and cleaned
•
The nose is lined with mucous membranes
- Produces mucous
- Moistens air
- Traps bacteria and dust particles
•
The nose is lined with cilia
- Tiny hair-like structures that are in constant motion
- Traps dust particles and bacteria
- Removes mucous
•
Located above the nasal cavity are the sinuses
- Hollow spaces
- Lined with mucous membranes
- When you have a cold in your sinuses they become clogged with mucous
•
In the back of the nasal cavity is the pharynx (throat)
•
The trachea (windpipe) is the pathway in which air moves from the pharynx to the
lungs.
- Rings of cartilage support the trachea to keep it from collapsing as you inhale
•
Larynx (voice box)
- Top of the trachea
- Made of cartilage
- Vocal cords create vibrations that produces sound
The Lungs:
•
Lung – elastic, spongy organs through which the body absorbs oxygen
•
Inside the lungs the trachea divides to from bronchi
- Bronchi are the tubes that go to each lung
•
Inside the lungs the bronchi divide into smaller tubes called the bronchioles
•
Located on each end of the bronchioles are tiny sacs called the alveoli
- The alveoli are surrounded by capillaries, where oxygen (O2) and carbon
dioxide (CO2) pass through the tiny walls in and out of the bloodstream.
What happens when you breathe?
•
Lungs have no muscles
•
Breathing is done from the diaphragm
- a muscle located in your chest and abdomen that lies just below your lungs
•
Inhalation – the diaphragm flattens downward, which pulls the rib
muscles up and out
- Chest cavity gets larger
- Air goes into the lungs
- Alveoli expand and fill with air
•
Exhalation – the diaphragm moves upward and the rib muscles drop
- Chest cavity drops
- Alveoli contract and the air is squeezed from the lungs
Disorders of the Respiratory System:
Respiratory Infections:
Influenza
- Commonly include fever, headache, muscle aches. Sore throat and a cough
- Treatment: Stay at home, resting, and drink plenty of water, sometimes
antibiotic if symptoms last more then a few days.
Pneumonia
- Is an infection in which fluids accumulate in the alveoli, decreasing the lungs’
ability to take in oxygen and eliminate carbon dioxide
- Treatment seek medical attention for an antibiotic
Tuberculosis or TB
- Is a chronic, or long-term, bacterial disease that affects the lungs and other parts
of the body.
- Symptoms of TB is fever, tiredness, weight loss, and an ongoing cough
Asthma:
- Is a disorder in which the air passages become narrower than normal
- The narrowing causes wheezing, coughing, and difficulty in breathing
- Can be caused by an allergy
Allergy – is a reaction of the body to an irritating substance
- Chronic problem
- No cure for asthma but some children with asthma will out grow the condition
- Asthma attacks can be controlled by allergy testing, medication, and inhalers.
Bronchitis:
- Is an inflammation and swelling of the membranes inside the bronchi tubes
- Symptoms are hoarseness and coughing (your body is trying to clear the
mucous)
- Treatment: rest, fluids and cough medicine
Emphysema:
- Is a respiratory disorder in which the alveoli lose their ability to expand and
contract
- Can not be cured
Effects of Air Pollution and Smoking:
• When you breathe everything in the air enters your respiratory system
Air pollution and smoking can severely damage the cilia inside your nose and lungs causing
mucous to build up, which then develops into a cough.