31.4 Immunity and Technology

KEY CONCEPTLiving 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 carriesgenes for antibioticresistance on a plasmid.

A copy of the plasmid is transferredthrough conjugation.

Resistance is quicklyspread throughmany 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

– allows immune system to respond quickly to infection

– causes memory cells to be produced

– has such a fast response, a person will not get sick

A memory B cell isstimulated when the real pathogen binds to it.

2

The B cell quickly activates and makes antibodies that fight the pathogens before you get sick.

3

Antigens in a vaccinetrigger an immune response, and memory B cells are made.

1memory B cells

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