Immune System Quiz
Questions: 16 · 10 minutes
1. A person receives ready-made antibodies shortly after a specific exposure. The protection is immediate but fades over time. What type of immunity is this?
Active immunity from natural infection
Innate immune memory
Passive immunity
Autoimmune tolerance
2. After an organ transplant, why might the recipient's immune system attack the donated organ?
The donated organ contains no cell-surface markers
Innate immunity always destroys every healthy organ
The donated organ begins producing pathogens after transplantation
Recipient lymphocytes may recognize donor cell markers as foreign
3. Which statement best describes how a moderate fever can contribute to immune defense?
It can hinder some pathogens and support certain immune processes
It guarantees that every pathogen in the body is destroyed
It prevents immune cells from communicating with one another
It creates antibodies without activating lymphocytes
4. During a throat infection, nearby lymph nodes may become enlarged and tender. What best explains this change?
The nodes are converting antibodies into red blood cells
The nodes are replacing damaged skin barriers
Immune cells are accumulating, activating, and multiplying there
Pathogens are always multiplying freely inside the nodes
5. Someone develops sneezing and itchy eyes after inhaling pollen. Which explanation best fits this response?
The immune system is attacking the body's own eye tissue
Pollen is directly destroying circulating immune cells
Memory cells have stopped recognizing all foreign material
The immune system is reacting to a normally harmless antigen
6. In an autoimmune condition, what is the central immune-system error?
Immune responses mistakenly target the body's own components
All innate defenses are replaced by adaptive defenses
Antibodies can recognize only bacterial antigens
The immune system cannot produce inflammation
7. A small cut becomes warm, red, and swollen within minutes. Which response is primarily responsible for these early changes?
Production of highly specific antibodies
Innate inflammation
Formation of long-lived memory cells
Autoimmune recognition of skin cells
8. Which antibody class is especially important in mucosal secretions such as saliva, tears, and breast milk?
IgD
IgA
IgE
IgM
9. Which immune cells can develop into plasma cells that secrete antibodies?
B lymphocytes
Cytotoxic T cells
Neutrophils
Natural killer cells
10. Which type of immune cell specializes in directly killing many virus-infected host cells after recognizing a specific antigen?
Mast cell
Cytotoxic T cell
Plasma cell
Helper T cell
11. A person develops repeated infections from microbes that rarely cause illness in people with typical immune defenses. What does this pattern most directly suggest?
An allergic response to harmless substances
A possible deficiency in one or more immune defenses
A normal increase in immune memory
An unusually strong physical skin barrier
12. A vaccinated person encounters the targeted pathogen months later and mounts a faster response. What best explains this?
Red blood cells retained and recognized the pathogen
The vaccine permanently strengthened every physical barrier
Memory cells formed after vaccination respond rapidly
Inflammation prevented all future exposure to the pathogen
13. Which structure normally acts as a first-line physical barrier that helps prevent pathogens from entering the body?
Memory B cells
Antibodies circulating in blood
Cytotoxic T cells
Intact skin
14. A dendritic cell engulfs a pathogen, travels to a lymph node, and displays pathogen fragments to a naïve T cell. What process is occurring?
Red blood cell maturation
Antibody neutralization
Antigen presentation
Complement-mediated lysis
15. A complement protein complex forms pores in a susceptible bacterium's membrane. What is the most direct likely result?
The bacterial cell membrane is disrupted, leading to lysis
The bacterium develops antigen-specific memory
The bacterium turns into an antibody-producing cell
The bacterial genome becomes part of a T cell
16. Why can a booster vaccination produce a quicker, stronger adaptive response than the first dose?
It converts innate immune cells into antibodies
It replaces the body's physical barriers
It prevents immune cells from recognizing other antigens
It reactivates antigen-specific memory cells