Unit 4 Lesson 2 Infectious Disease
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Unit 4 Lesson 2 Infectious Disease
Florida Benchmarks
• SC.6.L.14.6 Compare and contrast types of
infectious agents that may infect the human body,
including viruses, bacteria, fungi, and parasites.
• HE.6.C.1.4 Recognize how heredity can affect
personal health.
• HE.6.C.1.8 Explain how body systems are
impacted by hereditary factors and infectious
agents.
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Unit 4 Lesson 2 Infectious Diseases
Getting through Security
What is noninfectious disease?
• Different diseases have a specific set of
symptoms, or changes in how a person with an
illness feels.
• All diseases are categorized as noninfectious or
infectious diseases.
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Unit 4 Lesson 2 Infectious Diseases
Getting through Security
What is noninfectious disease?
• Noninfectious diseases cannot be spread from
person to person.
• Hereditary factors can cause noninfectious
diseases.
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Unit 4 Lesson 2 Infectious Diseases
What is noninfectious disease?
• Environmental factors can cause noninfectious
disease.
• Mutagens are substances that cause mutations, or
changes, in DNA that may result in disease.
• Cancer is a group of noninfectious diseases
caused by both hereditary and environmental
factors.
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Unit 4 Lesson 2 Infectious Diseases
What is infectious disease?
• A disease that is caused by a pathogen is called
an infectious disease.
• Living pathogens include bacteria, fungi, and
parasites.
• Viruses are pathogens that are noncellular. They
cannot function on their own.
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Unit 4 Lesson 2 Infectious Diseases
What is infectious disease?
• Infectious diseases can be passed from person to
person.
• Pathogens can be passed from nonliving objects
and from other living things.
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Unit 4 Lesson 2 Infectious Diseases
That’s Sick!
What can cause infectious disease?
• Viruses are tiny particles that have their own
genetic material and depend on living things to
reproduce.
• Influenza, the common cold, and HIV are
examples of diseases caused by viruses.
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Unit 4 Lesson 2 Infectious Diseases
What causes infectious disease?
• Many bacteria are beneficial to living things, but
some cause disease.
• Tuberculosis, strep throat, diarrheal illness, and
some sinus infections are caused by bacteria.
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Unit 4 Lesson 2 Infectious Diseases
What causes infectious disease?
• Most fungi are beneficial because they break down
dead plants and animals.
• Some fungi are pathogens.
• Athlete’s foot and ringworm are two common skin
infections caused by fungi.
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Unit 4 Lesson 2 Infectious Diseases
What causes infectious disease?
• A parasite is an organism that feeds on another
organism, called a host.
• Parasites harm their hosts.
• Malaria, giardiasis, and worm infections are
common parasitic infections.
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Unit 4 Lesson 2 Infectious Diseases
Don’t Pass It On
How can infectious diseases be
transmitted?
• Contagious diseases can be spread easily from
person to person or from other organisms to
people.
• Water and food supplies can be contaminated and
cause sickness.
• Diseases can be spread through the air, through
touching an infected person, and through sexual
contact.
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Unit 4 Lesson 2 Infectious Diseases
How can infectious diseases be
transmitted?
• Insects, ticks, and other animals can spread
disease.
• Objects that are handled by sick people or that
come in contact with infected animals or
contaminated food can pick up pathogens.
• Contaminated needles can transmit diseases.
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Unit 4 Lesson 2 Infectious Diseases
End Transmission
How can diseases be reduced?
• Improved personal hygiene and improved
technology have helped reduce the spread of
disease.
• Vaccines prevent serious illnesses worldwide.
• Food preservation techniques help reduce
contamination of foods with pathogens.
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Unit 4 Lesson 2 Infectious Diseases
How can disease be treated?
• Antibiotics are medicines used to kill or slow the
growth of bacteria and other microorganisms,
such as fungi.
• Antibiotics do not work on viruses.
• Antiviral drugs are drugs that destroy viruses or
prevent their replication.
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Unit 4 Lesson 2 Infectious Diseases
Resisting Arrest
• Some bacteria have developed a resistance to
antibiotics.
• Washing your hands throughout the day can
reduce the risk for some infections.
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