Transcript 31.4 Immunity and Technology

31.4 Immunity and Technology
KEY CONCEPT
Living in a clean environment and building immunity
help keep a person healthy.
31.4 Immunity and Technology
Many methods are used to control pathogens.
• Antibiotics and antiseptics cause pathogens to burst.
31.4 Immunity and Technology
• Antiseptics kill pathogens outside of the body.
– do not target specific pathogens
– examples include vinegar and soap
• Antibiotics kill pathogens inside the body.
– target one specific bacterium or fungus
– not effective against viruses
31.4 Immunity and Technology
• Antibiotic resistance can cause medicines to become
ineffective.
– Some bacteria in a population have genes that make
them immune to antibiotics.
– These bacteria spread the gene, making the antibiotics
useless.
A bacterium carries
genes for antibiotic
resistance on a plasmid.
A copy of the plasmid is transferred
through conjugation.
Resistance is quickly
spread through
many bacteria.
31.4 Immunity and Technology
Vaccines artificially produce acquired immunity.
• Vaccines also control pathogens and disease.
– given to prevent illness
– contain the antigen of a weakened pathogen
31.4 Immunity and Technology
9. What is a vaccine?
A substance that produces active immunity.
10. Why do vaccines do that allow the body do to gain
immunity without getting sick?
Produce memory cells
11. Memory cells do not have to be activated- they respond
right away.
12.Vaccines are made of : dead, whole pathogens, weak
pathogens, pieces of pathogens, bacterial toxins
31.4 Immunity and Technology
• Vaccination provides immunity.
– stimulates a specific
immune response
memory B cells
– causes memory
cells to be produced
– allows immune
system to respond
quickly to infection
– has such a fast
response, a person
will not get sick
Antigens in a vaccine
trigger an immune response,
and memory B cells are
made.
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A memory B cell is
stimulated when the real
pathogen binds to it.
The B cell quickly activates
and makes antibodies that
fight the pathogens before
you get sick.
31.4 Immunity and Technology
• 13. Antiseptics- destroy disease causing particles that
are outside the body.
• 14. What is an antibiotic resistance bacteria? pathogens
that survive in the presence of the antibiotic