BIOLOGY 1 – The majority of symptoms you experience when you get sick are part

13 Jun BIOLOGY 1 – The majority of symptoms you experience when you get sick are part

Question
The Immune Response

• The majority of symptoms you experience when you get sick are part of your body’s response to invading ____________________ (bacteria, viruses, fungi, allergens, venom, etc.)

• The first and second lines of defense against pathogens are known as non-specific defenses.

– Work against pathogens in ___________________

• The third line of defense, the immune system, is known as a specific defense.

– Target a __________________ pathogen

– Works at the same time as the non-specific

The Non-Specific Response

• There are two types: external and internal

• EXTERNAL (First line of defense):

– __________, saliva, _____________, and mucus in nose and throat

• INTERNAL (Second line of defense):

– Inflammatory Response

– Phagocytes (cells that kill bacteria indiscriminately.)

– _________________ (increase in body temp)

• Slows down or kills some pathogens

• Speeds up some immune mechanisms

The Specific Response (Third line of defense):

• Normal body cells have specific “self” markers that say “Hey! I’m supposed to be here!”

• Pathogens also have specific markers called ___________.

• Special WBC, called lymphocytes, patrol the body looking for antigens.

• There are two specific immune responses and two types of lymphocytes (________________)

• Antibodies (good guys) are specific for their antigen (gad guys).

1) Humoral Immunity is activated when antibodies recognize and bind to antigens on the surface of an invading pathogen.

• B CELLS

–Patrol body looking for _______________________

–Have a specific antibody that recognizes and ____________ to a specific antigen

• T CELLS

–Stimulates the ________________ to grow and divide

–Division creates 2 types of B Cells: _________________ and Memory B Cells

• PLASMA CELLS

–Produce and release antibodies

–Binding of antibody to antigen marks for destruction

–________________________once infection is over

• MEMORY B CELLS

–Same pathogen = _______________ response by Memory B Cells

–Memory B cells can produce new plasma cells very quickly

2) Cell-mediated immunity defends the body against invading pathogens that attack within body cells. This type of immunity uses T cells and does not involve antibodies.

• INVADER

–When a body cell is invaded by a pathogen the cell’s ________________ displays a portion of the pathogen’s antigen.

• HELPER T CELLS

–Recognize _________________ and begin to divide

–Activate Cytotoxic T Cells and produce Memory T Cells

• CYTOTOXIC T CELLS

–Recognize antigens on cell surface

–Injects cytotoxin into cell to destroy them and stop ________________ from spreading

• MEMORY T CELLS

–Same pathogen = fast response by Memory T Cells

Active vs. Passive Immunity

• Active immunity refers to the ACTIVE production of antibodies by a person’s own immune system.

– An active immunity that results from a person acquiring memory cells after recovering from an infectious disease is a naturally acquired active immunity.

– Deliberate exposure to an antigen through a vaccine results in an artificially acquired active immunity.

• Passive immunity occurs when a person is given the actual antibodies needed to fight off an infection from another source

– Naturally acquired passive immunity in utero and during breast feeding.

– Artificially acquired passive immunity (Injected with antibodies. Shorter lived but helpful in some cases.)

Check Your Understanding –

1. (4 points) The immune response requires a team effort. How do the specific and non-specific defenses work together? EXPLAIN YOUR ANSWER.

2. (4 points) Human Immunodeficiency Virus (HIV) is a virus that infects (and destroys) Helper T Cells. As a result, people who are HIV+ generally have a low number of these T Cells. How would a dramatic decrease in Helper T Cells affect a person’s immune response? Be specific using details from what you learned about the immune response.

3. (3 points) Label each example as either (PI) passive or (AI) active immunity:

a. ________ Bill had chicken pox when he was five. He doesn’t catch it again, even when his nephew gets sick with the virus.

b. _______ Billy Jr gets vaccinated with a live attenuated form of the chicken pox virus. He doesn’t get chicken pox after playing with his infected cousin.

c. _______ Bill’s 3 month old daughter is breast feeding. She does not get chicken pox after playing with her infected cousin.

4. (5 points) Compare and Contrast: Vaccines versus Antibiotics

Mark each statement as true for either (V)vaccines or (A)antibiotics.

a. _____ Work only against bacterial infections.

b. _____ Work only against viral infections.

c. _____ Immunity is provided by injecting a killed or live attenuated (weakened) type of virus into a person. The person’s own immune system then creates antibodies against the virus that keep them from becoming ill when they come in contact with it in the future.

d. _____ If used improperly, can cause bacteria to mutate and become resistant to the medication.

e. ____ Work because of the types of memory cells in our immune system.

5. (4 points) If a doctor wanted to run a blood test to determine whether or not a person was immune to the measles virus, would they need to look for measles antigens or measles antibodies? EXPLAIN YOUR ANSWER.

6. (20 points) For this question, you must create a Public Service Announcement. Your PSA can be in the form of a poster, short video, billboard, or paragraph. In it, please explain how vaccines work and discuss their importance in protecting the public health of our society. Be sure to include specific detail from today’s lesson in the “how it works” part. DON’T just say, “It keeps you from catching a virus.” Explain how it does that! You can insert a picture of your work below or attach a separate document.