What’s up with our Lungs What’s up with our Lungs and Respiratory System?and Respiratory System?

Why do we breathe?Why do we breathe?

Why we breatheWhy we breathe Our bodies need oxygen, one of Our bodies need oxygen, one of

several gasses in our air, to stay several gasses in our air, to stay alivealive

When we breathe air into our lungs, When we breathe air into our lungs, oxygen passes through the thin walls oxygen passes through the thin walls of the air sacs and into our bloodof the air sacs and into our blood

Our heart pumps the blood and Our heart pumps the blood and oxygen around our bodyoxygen around our body

Breathing cont’dBreathing cont’d The oxygen we breathe in mixes The oxygen we breathe in mixes

with a sugar called glucose, which with a sugar called glucose, which we get from our foodwe get from our food

Oxygen and Glucose combined Oxygen and Glucose combined give us energygive us energy

Energy produces water and the Energy produces water and the gas Carbon Dioxidegas Carbon Dioxide

Breathing cont’dBreathing cont’d Our body does not need these two Our body does not need these two

things together and carries them things together and carries them back to our lungs so we may back to our lungs so we may breathe them outbreathe them out

Our LungsOur Lungs Our lungs are one of the largest organs Our lungs are one of the largest organs

in our bodyin our body They work with our Respiratory system They work with our Respiratory system

to take in fresh air, expel stale air and to to take in fresh air, expel stale air and to help us talk help us talk

Our lungs take up most of the space in Our lungs take up most of the space in our chestsour chests

But they aren’t the same size (Left is a But they aren’t the same size (Left is a bit smaller, leaves room for our heart)bit smaller, leaves room for our heart)

Our LungsOur Lungs The right lung has 3 sections or lobesThe right lung has 3 sections or lobes The left has 2 lobesThe left has 2 lobes They are protected by our rib cageThey are protected by our rib cage Beneath our lungs is the diaphragm, Beneath our lungs is the diaphragm,

dome shaped muscle that works with dome shaped muscle that works with lungs to inhale and exhale airlungs to inhale and exhale air

From the outside healthy lungs are From the outside healthy lungs are pink and squishypink and squishy

LungsLungs The RIGHT LUNG is divided into

three LOBES, or sections. The left lung is divided into two

LOBES. The PLEURA are the two

membranes, that surround each lobe of the lungs and separate the lungs from the chest wall.

LungsLungs The DIAPHRAGM is the strong wall of

muscle that separates the chest cavity from the abdominal cavity. By moving downward, it creates suction to draw in air and expand the lungs.

The smallest subdivisions of the bronchi are called BRONCHIOLES, at the end of which are the alveoli (plural of alveolus).

LungsLungs The ALVEOLI are the very small air sacs

that are the destination of air breathed in. The CAPILLARIES are blood vessels that are imbedded in the walls of the alveoli. Blood passes through the capillaries, brought to them by the PULMONARY ARTERY and taken away by the PULMONARY VEIN. While in the capillaries the blood discharges carbon dioxide into the alveoli and takes up oxygen from the air in the alveoli.

Ribs and LungsRibs and Lungs The RIBS are bones supporting and

protecting the chest cavity. They move to a limited degree, helping the lungs to expand and contract.

The trachea divides into the two main BRONCHI (tubes), one for each lung. These, in turn, subdivide further into bronchioles.

Pharynx and EpiglottisPharynx and Epiglottis The PHARYNX (throat) collects

incoming air from the nose and passes it downward to the trachea (windpipe).

The EPIGLOTTIS is a flap of tissue that guards the entrance to the trachea, closing when anything is swallowed that should go into the esophagus and stomach.

Larynx,Esophagus and Larynx,Esophagus and TracheaTrachea The LARYNX (voice box) contains the

vocal cords. It is the place where moving air being breathed in and out creates voice sounds.

The ESOPHAGUS is the passage leading from the mouth and throat to the stomach.

The TRACHEA (windpipe) is the passage leading from the pharynx to the lungs.

Bronchial TubesBronchial Tubes The bronchial tubes are lined with CILIA

(like very small hairs) that have a wave-like motion. This motion carries MUCUS (sticky phlegm or liquid) upward and out into the throat, where it is either coughed up or swallowed. The mucus catches and holds much of the dust, germs, and other unwanted matter that has invaded the lungs and thus gets rid of it.

Bronchial TubesBronchial Tubes At the bottom of our trachea (windpipe) At the bottom of our trachea (windpipe)

there are 2 large tubes, Main stem there are 2 large tubes, Main stem bronchibronchi

One main stem bronchus (sing.) goes to One main stem bronchus (sing.) goes to the left, the other to the rightthe left, the other to the right

The main stem bronchus branches off The main stem bronchus branches off into bronchi (other tubes that get into bronchi (other tubes that get smaller and smaller, like tree branches)smaller and smaller, like tree branches)

The tiniest tubes are called bronchiolesThe tiniest tubes are called bronchioles

Bronchial Tubes and Bronchial Tubes and AveoliAveoli About 30,000 bronchioles in each lungAbout 30,000 bronchioles in each lung Each bronchiole is about the thickness Each bronchiole is about the thickness

of a hairof a hair At the end of each bronchiole are At the end of each bronchiole are

teeny tiny air sacs called aveoliteeny tiny air sacs called aveoli About 600 million aveoli in the lungs, About 600 million aveoli in the lungs,

stretched out they’d cover a tennis stretched out they’d cover a tennis courtcourt

AlveoliAlveoli Each alveolus (sing.) has mesh Each alveolus (sing.) has mesh

covering of small blood vessels covering of small blood vessels (capillaries- so small cells in blood (capillaries- so small cells in blood need to line up single file to pass need to line up single file to pass through)through)

When we InhaleWhen we Inhale Diaphragm contracts and flattens Diaphragm contracts and flattens

out, moves down so lungs have out, moves down so lungs have more room to get larger as they fill more room to get larger as they fill with waterwith water

Rib muscles also lift ribs up and Rib muscles also lift ribs up and outward to give lungs more spaceoutward to give lungs more space

On the way down the windpipe, the On the way down the windpipe, the tiny hairs (cilia) move to keep mucus tiny hairs (cilia) move to keep mucus and dirt out of lungsand dirt out of lungs

InhalingInhaling Air then goes through bronchi and Air then goes through bronchi and

bronchioles (series of branches)bronchioles (series of branches) Air finally reaches 600 million alveoliAir finally reaches 600 million alveoli As the millions of alveoli fill up with As the millions of alveoli fill up with

air, the lungs get biggerair, the lungs get bigger The alveoli allow oxygen from the air The alveoli allow oxygen from the air

to pass into the bloodto pass into the blood

Inhaling cont’dInhaling cont’d All cells in the body need oxygen All cells in the body need oxygen

every minuteevery minute Oxygen enters blood in the Oxygen enters blood in the

capillaries and hitches a ride on red capillaries and hitches a ride on red blood cells traveling through layers blood cells traveling through layers of blood vessels to the heartof blood vessels to the heart

The heart then sends all oxygenated The heart then sends all oxygenated blood out to cells in the bodyblood out to cells in the body

ExhalingExhaling The reverse, diaphragm moves up, The reverse, diaphragm moves up,

pushing air out, rib muscles relax, ribs pushing air out, rib muscles relax, ribs move in move in

Cells have used oxygen, blood carries Cells have used oxygen, blood carries out CO2 – Carbon dioxide and other out CO2 – Carbon dioxide and other wastes that must leave the bodywastes that must leave the body

Lungs covered by pleural membranes Lungs covered by pleural membranes that keep junk from getting in that keep junk from getting in

Other Parts of the Other Parts of the Respiratory SystemRespiratory System

The SINUSES are hollow spaces in the bones of the head. Small openings connect them to the nasal cavity. The functions they serve are not clearly understood, but include helping to regulate the temperature and humidity of air breathed in, as well as to lighten the bone structure of the head and to give resonance to the voice.

Oral CavityOral Cavity Air also enters through the ORAL

CAVITY (mouth), especially in people who have a mouth-breathing habit or whose nasal passages may be temporarily obstructed, as by a cold.

Nasal CavityNasal Cavity The NASAL CAVITY (nose) is the

preferred entrance for outside air into the Respiratory System. The hairs that line the inside wall are part of the air-cleansing system.

AdenoidsAdenoids The ADENOIDS are overgrown lymph

tissue at the top of the throat. When they interfere with breathing, they are generally removed. The lymph system, consisting of nodes (knots of cells) and connecting vessels, carries fluid throughout the body. This system helps resist body infection by filtering out foreign matter, including germs, and producing cells (lymphocytes) to fight them.

TonsilsTonsils The TONSILS are lymph nodes in

the wall of the pharynx that often become infected. They are an unimportant part of the germ-fighting system of the body. When infected, they are generally removed.

SourcesSources www.kidshealth.orgwww.kidshealth.org, Looking at , Looking at

Your LungsYour Lungs Kittredge, Mary. Kittredge, Mary. The Respiratory The Respiratory

SystemSystem. Philadelphia: Chelsea . Philadelphia: Chelsea House Publishers, 2000.House Publishers, 2000.

Other ResourcesOther Resources Parker, Steve. Parker, Steve. LungsLungs. Brookfield, . Brookfield,

Connecticut: Copper Beech Books, 1996.Connecticut: Copper Beech Books, 1996. Parker, Steve. Parker, Steve. The Lungs and Respiratory The Lungs and Respiratory

SystemSystem. Austin, Texas: Raintree Steck-. Austin, Texas: Raintree Steck-Vaugn Publishers.Vaugn Publishers.

Stille, Darlene. Stille, Darlene. The Respiratory SystemThe Respiratory System. . New York, NY: Children’s Press, 1997.New York, NY: Children’s Press, 1997.

Ylvisaker, Anne. Ylvisaker, Anne. Your LungsYour Lungs. Mankato, . Mankato, Minnesota: Capstone Press, 2002. Minnesota: Capstone Press, 2002.