Keeping Your Body Healthy
- Immune System –
- Respiratory System Lesson 19
Quick Quiz Complete each of these statements with always, sometimes, or
never.
I ____ wash my hands before meals.
When preparing fruits and vegetables, I ____ wash them thoroughly.
I am ____ careful to use only my own eating utensils, drinking cups,
towels and grooming items.
I ____ cover my mouth when I cough or sneeze.
If I spend time in wooded areas, I ____ wear
insect repellent.
For each of your responses, explain how your behavior could affect
your chances of getting or spreading an
infectious disease.
Health Stats What does the graph suggest about asthma rates?
Describe some factors that could contribute to the rise and fall of
asthma rates.
Goals/Objectives
• Identify the parts and functions of the
immune and respiratory systems.
• Identify behaviors to keep your immune and
respiratory systems healthy.
• Describe how air travels through your
respiratory system, and how you breathe.
Key Terms
• Immune system
• Respiratory system
• Asthma
The Immune System
• The body system that removes harmful
organisms from the blood and combats
pathogens is the immune system.
• Protects your body from pathogens
– Pathogen – a disease causing germ
The Immune Response
•When a pathogen enters your body for the first time, it
often causes disease.
•White blood cells called lymphocytes carry out most of
the immune system’s functions.
•If a pathogen that has previously attacked your body
enters your body again your immune system will quickly
recognize the pathogen and launch an immediate attack.
•Immunity is your body’s ability to destroy pathogens that it
has previously encountered before the pathogens are able to
cause disease.
T Cells
T cells perform several functions.
•Killer T cells destroy any body cell that has
been infected by a pathogen.
•Helper T cells produce chemicals that
stimulate other T cells and B cells to fight off
infection.
•Suppressor T cells produce chemicals that
“turn off” other immune system cells when
an infection has been brought under control.
B Cells
•The B lymphocytes, or B cells, produce antibodies.
•Antibodies are proteins that attach to the surface of
pathogens or to the toxins produced by pathogens.
•This binding action keeps the pathogen or toxin from
harming the body.
•The memory capacity of B cells explains why you develop
immunity to some diseases you’ve already had.
The Immune Response
The Lymphatic System
•The lymphatic system is a network of vessels that
collects fluid from your tissues and returns it to
the bloodstream.
•The fluid flowing through the lymphatic system is
called lymph (limf).
•The lymphatic vessels have hundreds of small
stations, called lymph nodes.
The Lymphatic System
Your lymphatic system is a
complex network of vessels
and nodes.
Lymph
nodes
Lymph
vessel
How to Keep Your
Immune System Healthy
• Choose foods that are high in protein and
vitamin B.
• Keep accurate records of all immunizations.
• Get plenty of rest and sleep.
• Exercise to keep bones dense and to protect
bone marrow.
The Respiratory System
• The body system that provides body cells with
oxygen and removes carbon dioxide that cells
produce as waste is the respiratory system.
The Pathway of Air
On its way to the lungs, air passes through
the
•nose
•pharynx
•larynx
•trachea
•bronchi
Cilia
Cilia line most of the respiratory tract. Cilia
capture mucus that contains dust and
microorganisms and sweep it toward your
throat to be swallowed.
The Respiratory System
Trachea
Nose
and Nasal Cavities
Air enters
The
trachea,
theorbody
windpipe,
through
leads
two
nostrils
from
theand
larynx
thentomoves
the lungs.
into the
nasal cavities.
Bronchus
Pharynx
The trachea divides into two
Next air enters the pharynx, or
bronchi, which are cartilage-ringed
throat. The mouth also connects to
tubes that enter each lung.
the pharynx.
Epiglottis and Larynx
Lung
Airthe
travels
from
the pharynx
to the
In
lungs,
bronchi
divide like
larynx. The
the
branches
oflarynx
a tree contains
into smaller
vocal cords.
tubes.
At theWhen
end ofyou
theswallow,
smallestthe
epiglottis
the larynx
to and
tubes
are seals
the alveoli.
Oxygen
preventdioxide
food orare
liquid
from in
carbon
exchanged
entering the trachea.
alveoli.
Gas Exchange
•At the end of the smallest tubes in the
lungs are millions of tiny sacs that look
like bunches of grapes.
•These sacs, called alveoli are where
gases are exchanged between the air
and the blood.
Alveoli
Blood rich in
carbon dioxide
Blood rich
in oxygen
Capillary
The Breathing Process
The breathing process is controlled by the actions of muscles in your ribs and
chest.
• Inhalation
• When you inhale, the diaphragm, a dome-shaped muscle that
lies below the lungs, flattens.
• The chest cavity enlarges, the volume of the lungs increases, and
air flows in.
• Exhalation
• When you exhale, or breathe out, the diaphragm moves
upward.
• The rib muscles relax and the ribs drop.
• These movements make the chest cavity smaller and squeeze
air from the lungs.
Inhalation
Exhalation
The volume of the
The volume of the lungs
lungs increases, and
decreases, and air is
air flows in.
pushed out.
Keeping Healthy
You can keep your respiratory system healthy by:
•avoiding tobacco smoke and air pollution
•treating asthma if you have it
•avoid respiratory infections
•get regular exercise
•maintain a healthy weight
Avoiding Smoking and Air
Pollution
•The most important think you can do to protect your
respiratory system is not to smoke.
•It is also important to avoid exposure to air pollutants
whenever possible.
• If you do work that generates fumes or dust wear a mask.
• Work in a well-ventilated area when you paint or use other
chemicals.
• Before exercising outdoors on a hot, sunny day, check local
news reports for warnings about air quality.
Living With Asthma
•Asthma is a disorder in which respiratory passageways
become inflamed.
•During an asthma attack, the passageways narrow until
air can barely pass through.
•As a result, the person wheezes, coughs, and has difficulty
breathing.
Other Healthful Behaviors
•Avoid Respiratory Infections Bronchitis is an infection
that causes the mucous membranes lining the bronchi to
become inflamed.
•Get Regular Exercise Exercise helps your lungs become
more efficient at taking in oxygen and eliminating carbon
dioxide.
•Maintain a Healthy Weight The respiratory system of an
overweight person must work harder to deliver adequate
oxygen than the system of a normal weight person.
How to Keep Your
Respiratory System Healthy
•
•
•
•
•
•
•
Do no smoke.
Avoid breathing secondhand smoke.
Do not inhale harmful drugs.
Avoid breathing polluted air.
Exercise regularly.
Avoid inhaling harmful chemicals.
Seek medical help for respiratory infections.
Questions
1.
2.
3.
4.
5.
6.
7.
8.
What is a pathogen?
What is immunity?
Why do you think that some teens risk taking their asthma
medication?
Why wasn’t Alexandria’s asthma diagnosed right away?
In your own words, describe what happens during an asthma
attack. How is asthma treated?
Why is it important for people with asthma to pat attention to
weather reports?
What are some things that schools can do to reduce the risks of
asthma attacks?
Describe what happed to Briana that convinced her she needed to
get her asthma under control?