How the body defends itself: immunity, vaccines and antibiotics
Grade 9 Science Worksheet - Building Confidence

Circle the best answer.
Ari reads a map of the body's defenses. Box X is the first line, a barrier at the body surface. What is box X?
- Phagocytes, cells that engulf microbes
- Memory cells, cells kept after a response
- Antibodies, proteins that match one antigen
- Skin and mucus, barriers at the body surface
Bo reads the map of the body's defenses. Box Y holds second-line cells that engulf and digest microbes. What is box Y?
Map of the body's defenses (model, not to scale). Arrows, each marked with what it carries: microbe to skin and mucus, meets a barrier; skin and mucus to inflammation and fever, a microbe gets past; inflammation and fever to box Y, calls in; box Y to T cells, shows antigen pieces; T cells to B cells, sends an activation signal; B cells to antibodies, make; B cells to memory cells, some become. Map of the body's defenses (model, not to scale). Arrows, each marked with what it carries: microbe to skin and mucus, meets a barrier; skin and mucus to inflammation and fever, a microbe gets past; inflammation and fever to box Y, calls in; box Y to T cells, shows antigen pieces; T cells to B cells, sends an activation signal; B cells to antibodies, make; B cells to memory cells, some become. Map of the body's defenses model, not to scale skin and mucus inflammation and fever Y a microbe gets past calls in microbe meets a barrier T cells shows antigen pieces B cells sends an activation signal antibodies memory cells make some become - T cells, specific cells that act in minutes
- B cells, cells that make antibodies
- Skin and mucus, barriers at the body surface
- Phagocytes, cells that engulf microbes
Esme reads the map of the body's defenses. Phagocytes show antigen pieces to box Z, which then signals B cells. What is box Z?
Map of the body's defenses (model, not to scale). Arrows, each marked with what it carries: microbe to skin and mucus, meets a barrier; skin and mucus to inflammation and fever, a microbe gets past; inflammation and fever to phagocytes, calls in; phagocytes to box Z, shows antigen pieces; box Z to B cells, sends an activation signal; B cells to antibodies, make; B cells to memory cells, some become. Map of the body's defenses (model, not to scale). Arrows, each marked with what it carries: microbe to skin and mucus, meets a barrier; skin and mucus to inflammation and fever, a microbe gets past; inflammation and fever to phagocytes, calls in; phagocytes to box Z, shows antigen pieces; box Z to B cells, sends an activation signal; B cells to antibodies, make; B cells to memory cells, some become. Map of the body's defenses (model, not to scale) microbe skin and mucus meets a barrier inflammation and fever a microbe gets past phagocytes calls in box Z shows antigen pieces B cells sends an activation signal antibodies make memory cells some become - Memory cells, cells kept after a response
- T cells, cells that signal B cells
- Skin and mucus, barriers at the body surface
- Antibodies, proteins that fit any microbe
Map of how a vaccine prepares the body (model, not to scale). Jun reads a map of how a vaccine prepares the body. B cells make the proteins in the blank box. What belongs in the blank box?
Map of how a vaccine prepares the body (model, not to scale). Arrows, each marked with what it carries: vaccine to phagocytes, antigen pieces; phagocytes to T cells, shows antigen pieces; T cells to B cells, sends an activation signal; B cells to the blank box, make; B cells to memory cells, some become. Map of how a vaccine prepares the body (model, not to scale). Arrows, each marked with what it carries: vaccine to phagocytes, antigen pieces; phagocytes to T cells, shows antigen pieces; T cells to B cells, sends an activation signal; B cells to the blank box, make; B cells to memory cells, some become. vaccine phagocytes T cells B cells antigen pieces shows antigen pieces sends an activation signal make memory cells some become - Phagocytes, cells that engulf microbes
- Fever, a rise in body temperature
- Antibodies, proteins that match an antigen
- Skin and mucus, barriers at the body surface
Map of the body's defenses (model, not to scale). Kira reads the map of the body's defenses. A microbe that gets past skin and mucus meets the blank box, which calls in phagocytes. What belongs there?
Map of the body's defenses (model, not to scale). Arrows, each marked with what it carries: microbe to skin and mucus, meets a barrier; skin and mucus to the blank box, a microbe gets past; the blank box to phagocytes, calls in; phagocytes to T cells, shows antigen pieces; T cells to B cells, sends an activation signal; B cells to antibodies, make; B cells to memory cells, some become. Map of the body's defenses (model, not to scale). Arrows, each marked with what it carries: microbe to skin and mucus, meets a barrier; skin and mucus to the blank box, a microbe gets past; the blank box to phagocytes, calls in; phagocytes to T cells, shows antigen pieces; T cells to B cells, sends an activation signal; B cells to antibodies, make; B cells to memory cells, some become. microbe skin and mucus phagocytes T cells B cells antibodies memory cells meets a barrier a microbe gets past calls in shows antigen pieces sends an activation signal make some become - Inflammation and fever, second-line responses
- Memory cells, cells kept after a response
- T cells, cells that signal B cells
- Antibodies, proteins that match one antigen
Read this first
Use this
Two maps (model data, not to scale) of antibody levels after a second exposure to the same microbe, once memory cells have formed.
Noah compares two maps of a second exposure to the same microbe. Which case matches how memory cells change the response?
Two maps (model data, not to scale) of antibody levels after a second exposure to the same microbe, once memory cells have formed. Case 1: antibodies rise after 10 days and reach a peak of 20. Case 2: antibodies rise after 3 days and reach a peak of 200. Two maps (model data, not to scale) of antibody levels after a second exposure to the same microbe, once memory cells have formed. Case 1: antibodies rise after 10 days and reach a peak of 20. Case 2: antibodies rise after 3 days and reach a peak of 200. Case 1 Case 2 antibodies rise antibodies rise 10 days 3 days peak 20 peak 200 - Case 2, because memory cells give a faster, higher response
- Case 1, because memory cells make the response slower
- Case 1, because the response is the same each time
- Case 2, because a faster, higher response needs a new microbe
Pia compares two maps of an antibody meeting an antigen with a triangle tip. Which case shows an antibody that can bind it?
Two maps (model, not to scale) of an antibody meeting the same antigen, which has a triangle tip. Case 1: the antibody has a triangle notch and meets the antigen. Case 2: the antibody has a round notch and meets the antigen. Two maps (model, not to scale) of an antibody meeting the same antigen, which has a triangle tip. Case 1: the antibody has a triangle notch and meets the antigen. Case 2: the antibody has a round notch and meets the antigen. model, not to scale Case 1 antibody antigen Case 2 antibody antigen - Case 1, because its notch matches the antigen's shape
- Case 1, because both parts are drawn at the same height
- Case 2, because a round notch grips better
- Case 2, because any antibody can bind any antigen
Antibiotic card (CDC facts)
kind of germ what CDC says about antibiotics bacteria can treat certain infections caused by bacteria viruses do not work on the viruses that cause a cold or the flu Ren reads an antibiotic card. According to the card, do antibiotics work on the viruses that cause a cold or the flu?
- Yes, they work on any kind of germ
- No, they do not work on viruses
- Yes, if they are taken for a longer time
- Yes, on the cold but not on the flu
Tala reads a graph of antibody level after a first and a second exposure to one microbe. Which exposure gave the higher level at day 7?
Model graph of antibody level after two exposures (model data). Days since the exposure (days) across, 0 to 28, a mark every 7. Antibody level (arbitrary units) up, 0 to 40, a mark every 10. The first exposure line joins (0, 0), (7, 2), (14, 10), (21, 6), (28, 3). The second exposure line joins (0, 0), (7, 40), (14, 20), (21, 10), (28, 5). Model graph of antibody level after two exposures (model data). Days since the exposure (days) across, 0 to 28, a mark every 7. Antibody level (arbitrary units) up, 0 to 40, a mark every 10. The first exposure line joins (0, 0), (7, 2), (14, 10), (21, 6), (28, 3). The second exposure line joins (0, 0), (7, 40), (14, 20), (21, 10), (28, 5). Model graph of antibody level after two exposures (model data) 0 7 14 21 28 0 10 20 30 40 Days since the exposure (days) Antibody level (arbitrary units) first exposure line second exposure line - The first exposure
- Both lines are level
- Neither line has risen
- The second exposure
Vaccine card (CDC facts)
vaccine form what it contains active ingredient whole microbe a weakened or inactivated microbe an antigen pieces bits of the microbe's outside or genetic material an antigen toxin a bacterial toxin made harmless an antigen Zee reads a vaccine card. According to the card, what is the active ingredient in each form of vaccine?
- Memory cells grown for the person
- An antigen from the microbe
- Ready-made antibodies for the microbe
- An antibiotic that removes the virus