The Respiratory System

Functions of the Respiratory System

• This is the body system that allows oxygen from the air to enter the blood and carbon dioxide from the blood to exit into the air

• When you inhale (breathe in), oxygen enters the blood stream and

• When you exhale (breathe out)carbon dioxide is removed from the blood

• This body system works closely with the cardiovascular system to do its job

The Respiratory System

Terms to know• Pharynx Diaphragm• Larynx pneumonia• Alveoli bronchitis• Bronchi asthma• Bronchiole• Epiglottis• Trachea• Lungs• Cilia/mucus• Pulmonary• Emphysema

• Air enters the nose, travels down the nasal passageway, down the pharynx (throat), larynx (voice box), trachea, bronchi, bronchiole, alveoli

Pharynx

• A funnel shaped passageway that connects the nasal and oral cavities to the larynx

• This is also known as the throat• In the pharynx, both food passage and air

passage cross

Larynx A cartilaginous structure that serves as a

passageway for air between the pharynx and the trachea

Also known as the voice box, because it houses the vocal cords

When air is expelled past the vocal cords, sound is produced

The length of the cords affects whether you have high or low tones- short and contracted cords=high voice, long and relaxed= lower voice

At the time of puberty, the growth of the larynx is more rapid and more accentuated in males than in females, causing the male to have a deeper voice and a more prominent Adam’s apple.

Bronchi and Bronchiole The trachea divides into

right and left primary bronchi which lead to the right and left lungs

The bronchi branch into a great number of secondary bronchi that lead to smaller branches called bronchioles

Each bronchiole leads to a multitude of air pockets, or sacs, called alveoli

Trachea

• The trachea is also known as the windpipe and is a tube connects to the bronchi

• It lies just above the esophagus and is held open by C- shaped cartilaginous rings

• The C shape rings face the esophagus so that the esophagus can expand when swallowing

• The inside of the trachea is lined with mucus as well as microscopic hair like structures called cilia

Cilia and Mucus Protect the Lungs

When you cough, it is because foreign material has entered the respiratory tract

What is causing the cough is the sweeping motion of cilia in the trachea, microscopic hair-like structures, which sweep away this material upward so that it leaves the body through the mouth

Mucus is a sticky substance that helps trap in foreign material that has entered the tract, which the cilia then sweep out

Together, the cilia and the secreted mucus help keep harmful substances out of the lungs

CILIA MAGNIFIED-they sweep about ten times a second, 24 hours a day to

keep you healthy!!

AlveoliThe alveoli are tiny, microscopic, air sacs where gas exchange in the lungs takes place. You have about 300 million per lung!

They have the appearance of grape-like clusters

Oxygen enters the blood through the alveoli and carbon dioxide leaves the

blood through the alveoli

The Lungs

• The lungs are paired, cone-shaped organs that occupy the thoracic cavity, except for the central area that contains the trachea, heart, and esophagus

• The right lung has three lobes and the left lung has two lobes

• Each lung is enclosed by a double layer of serous membrane called pleura. The pleura produces a lubricating fluid that allows the two layers to slide past each other. Surface tension holds the two pleura together when the lungs recoil during expiration

The right lung has 3 lobes. The left lung has 2 lobes.

The epiglottis is a flap of tissue that closes over the trachea

when you swallow, so food does not enter your lungs.

DIAPHRAGMA strong muscle that makes breathing possible. When the diaphragm moves downward, the lungs fill with air and the chest expands, resulting in inhalation. When the diaphragm moves upward, the air is forced out of the lungs, resulting in exhalation.

Emphysema A chronic and incurable disease in which alveoli are distended and

their walls damaged so that the surface area available for gas exchange is reduced

The elastic recoil of the lungs is reduced, so not only are the airways narrowed, but the driving force behind expiration is also reduced

The victim becomes breathless and may have a cough Because gas exchange is reduced, less oxygen reaches the heart

and the brain, causing the heart to work much harder to force more blood to the lungs

Lack of oxygen to the brain can make a person feel depressed, sluggish, and irritable

There is no cure- treatment goal is to slow down the progress of the disease. Treatment= exercise, drug therapy, and supplemental oxygen

• The alveoli in someone with emphysema begin to lose their elasticity and form, and the capillaries around them begin to lose their shape

• This disease is caused almost entirely by smoking

Which lung do you want to be doing the breathing work in your body?

Emphysema Healthy lung

Pneumonia

• Lung disease caused by a bacteria or virus• Symptoms include fever, chest pain, breathing

difficulty• Treatment- bacterial pneumonia treated with

antibiotics viral pneumonia requires bed rest to

get better

Asthma

Disease in which the airways narrowSymptoms include wheezing, shortness of breath, cough, fatigue, can be fatalAsthmatics must avoid activities that trigger an asthma attack

Lung Cancer

• Uncontrolled growth of cells that reproduce abnormally in the lungs: often caused by smoking

• Treated by surgery, radiation, medicine- survival rates are very low

Pulmonary Edema

Shortness of breath during physical activity is a sign of heart failure. Heart failure can lead to fluid leaking into the lungs. The left ventricle is unable to pump blood efficiently in heart failure. So blood begins to pool in the pulmonary circulation. This back up is under increased pressure as the right side of the heart is still pumping blood into the lungs. As a result, fluid leaks into the lungs, this is called pulmonary edema. Also, fluid retention by the kidneys causes pulmonary edema.

Ways to Care for your Lungs

• Don’t smoke!• Avoid people or situations that would expose you to

tobacco smoke in the air• Wear appropriate masks when exposed to harmful

fumes• Take care of your body when you have a cold, flu, or

other respiratory illness• Engage in regular aerobic type of activities, such as

biking and joggingIf a cough persists for more than a week, see a doctor…

How Does Tobacco Affect the Lungs?• It paralyzes cilia, so they don’t work as well• It causes the lungs to produce more mucus (too much

can cause lung complications)• It causes red blood cells to carry less oxygen, so

breathing is more difficult (carbon monoxide attaches to red blood cells and robs them of some oxygen)

• It can lead to damaged alveoli (emphysema)• Tar, a carcinogen, coats the lungs

• There are more than 4,000 chemicals in tobacco, of that amount, 40-60 are known carcinogens (cancer causing agents)! Each year in the U.S., approximately 400,000 people die from smoking related illnesses.

Nicotine is a stimulant- it speeds up heart rate and constricts blood vessels

Hookah Pipes- common in Middle Eastern countries

But gaining in popularity here in the U.S., along with cigar bars.Hookah pipes are used with sheesha flavored tobacco, which like all tobacco products, does contain nicotine.Smoking one round of a hookah smoke is like smoking 20 cigarettes- loaded with harmful chemicals!

Tidal Volume and Vital Capacity

Ways to Care for your Respiratory System

• Avoid smoking any type of tobacco• Avoid breathing in second hand smoke

Lung Cancer

Cellular Respiration Review

• Cellular respiration, which produces ATP, uses the oxygen brought in the blood, and gives off carbon dioxide

• Question…What is the waste product given off during exhalation?

•

Alveoli• The alveoli are surrounded

by blood capillaries where diffusion takes place

• Gas exchange occurs between the air in the alveolus and the blood in the capillaries

• This is where oxygen enters the blood and carbon dioxide exits the blood