1
- What does susceptibility mean in the context of host defenses?
- A) Ability to resist disease
- B) Lack of resistance to disease
- C) Immunity against a specific pathogen
- D) Adaptive immunity
B
2
- What is the primary function of the immune system?
- A) To produce red blood cells
- B) To ward off disease
- C) To transport oxygen
- D) To digest food
B
3
- What is nonspecific resistance also known as?
- A) Adaptive immunity
- B) Innate immunity
- C) Passive immunity
- D) Acquired immunity
B
4
- What type of immunity is slower to respond but has a memory component?
- A) Nonspecific resistance
- B) Innate immunity
- C) Specific resistance
- D) Temporary immunity
C
5
- Which physical factor involves the tightly packed cells with keratin?
- A) Mucous membranes
- B) Skin
- C) Ciliary escalator
- D) Lacrimal apparatus
B
6
- What is the role of mucous membranes in host defense?
- A) To secrete sebum
- B) To trap microbes
- C) To produce antibodies
- D) To filter blood
B
7
- What mechanism transports microbes trapped in mucus away from the lungs?
- A) Peristalsis
- B) Ciliary escalator
- C) Defecation
- D) Vomiting
B
8
- Which fluid washes away microbes from the eyes?
- A) Saliva
- B) Urine
- C) Vaginal secretions
- D) Tears
D
9
- What substance in saliva helps prevent colonization of teeth by microbes?
- A) Lysozyme
- B) Sebum
- C) Gastric juice
- D) Earwax
A
10
- Which of the following prevents microbes from entering the ear?
- A) Tears
- B) Urine
- C) Earwax
- D) Saliva
C
11
- What is the pH of the skin that inhibits the growth of pathogens?
- A) 7
- B) 5
- C) 3
- D) 9
B
12
- What enzyme found in perspiration, tears, and saliva destroys cell walls of microbes?
- A) Pepsin
- B) Amylase
- C) Lysozyme
- D) Lactase
C
13
- What pH range of gastric juice kills most microbes?
- A) 1.2 - 3.0
- B) 4.0 - 6.0
- C) 6.0 - 7.5
- D) 7.5 - 8.5
A
14
- What is microbial antagonism also known as?
- A) Commensalism
- B) Parasitism
- C) Competitive exclusion
- D) Mutualism
C
15
- Which bacteria produce bacteriocins that inhibit the growth of Salmonella and Shigella?
- A) Streptococcus
- B) E. coli
- C) Staphylococcus
- D) Bacillus
B
16
- How many bacteria are there approximately on a human body?
- A) 1 x 10^6
- B) 1 x 10^8
- C) 1 x 10^12
- D) 1 x 10^14
D
17
- What is the normal range of white blood cell count per cubic millimeter?
- A) 2,000–5,000
- B) 5,000–10,000
- C) 10,000–15,000
- D) 15,000–20,000
B
18
- What percentage of white blood cells are neutrophils?
- A) 20% to 25%
- B) 3% to 8%
- C) 2% to 4%
- D) 60% to 70%
D
19
- Which cells are involved in specific immunity?
- A) Neutrophils
- B) Monocytes
- C) Lymphocytes
- D) Eosinophils
C
20
- What are the cells that differentiate into macrophages called?
- A) Eosinophils
- B) Monocytes
- C) Basophils
- D) Lymphocytes
B
21
- Where are dendritic cells commonly found?
- A) Bloodstream
- B) Skin and mucous membranes
- C) Bone marrow
- D) Lymph nodes
B
22
- What is the primary function of lymphocytes?
- A) Phagocytosis
- B) Oxygen transport
- C) Specific immunity
- D) Blood clotting
C
23
- Which cells release histamine during an allergic reaction?
- A) Neutrophils
- B) Eosinophils
- C) Basophils
- D) Monocytes
C
24
- What is the role of phagocytes in the immune system?
- A) Produce antibodies
- B) Destroy pathogens by engulfing them
- C) Secrete mucus
- D) Produce histamine
B
25
- What are fixed macrophages that reside in the liver called?
- A) Microglia
- B) Kupffer cells
- C) Osteoclasts
- D) Langerhans cells
B
26
- What do free (wandering) macrophages do?
- A) Remain fixed in tissues
- B) Roam tissues and gather at sites of infection
- C) Secrete digestive enzymes
- D) Produce antibodies
B
27
- Which phase of phagocytosis involves the attraction of phagocytes to microorganisms?
- A) Adherence
- B) Chemotaxis
- C) Ingestion
- D) Digestion
B
28
- What is opsonization in the context of phagocytosis?
- A) The attachment of a phagocyte to the surface of a microorganism
- B) The coating of a microorganism with serum proteins
- C) The ingestion of a microorganism by a phagocyte
- D) The digestion of a microorganism inside a phagolysosome
B
29
- What are toll-like receptors (TLRs) involved in?
- A) Oxygen transport
- B) Pathogen recognition
- C) Hormone secretion
- D) Protein synthesis
B
30
- Which cells play a role in the inflammatory response by releasing cytokines?
- A) Red blood cells
- B) Neutrophils
- C) T-helper cells
- D) Platelets
C
31
- What are the cardinal signs of inflammation?
- A) Redness, pain, heat, swelling, loss of function
- B) Fever, nausea, fatigue, headache, dizziness
- C) Coughing, sneezing, sore throat, runny nose, congestion
- D) Itching, rash, swelling, hives, fever
A
32
- Which phase of the inflammatory response involves the increase in permeability of blood vessels?
- A) Chemotaxis
- B) Adherence
- C) Edema
- D) Diapedesis
C
33
- What chemical is responsible for vasodilation during inflammation?
- A) Histamine
- B) Lysozyme
- C) Pepsin
- D) Amylase
A
34
- Which cells produce interleukin-1 (IL-1) during an inflammatory response?
- A) Red blood cells
- B) Macrophages
- C) Platelets
- D) Eosinophils
B
35
- What does IL-1 stimulate in the hypothalamus?
- A) Decreased metabolism
- B) Increased appetite
- C) Release of prostaglandins
- D) Production of antibodies
C
36
- Which organ produces serum proteins that assist in destroying microbes?
- A) Kidney
- B) Heart
- C) Liver
- D) Pancreas
C
37
- What does complement activation result in?
- A) Protein synthesis
- B) Phagocytosis
- C) Cytolysis, opsonization, inflammation
- D) Hormone secretion
C
38
- Which pathway of complement activation involves antibodies?
- A) Alternative pathway
- B) Classical pathway
- C) Lectin pathway
- D) Direct pathway
B
39
- What components combine to activate C3 in the classical pathway?
- A) C1 and C4
- B) C2 and C4
- C) B and D
- D) C1 and C2
B
40
- What is the role of C3b in the complement system?
- A) Inflammation
- B) Cytolysis
- C) Opsonization
- D) All of the above
D
41
- Which pathway of complement activation does not involve antibodies?
- A) Classical pathway
- B) Lectin pathway
- C) Alternative pathway
- D) Direct pathway
C
42
- What factors combine with C3 in the alternative pathway?
- A) A, B, C
- B) B, D, P
- C) C1, C2, C4
- D) E, F, G
B
43
- What results from the activation of C3a in the complement system?
- A) Phagocytosis
- B) Cytolysis
- C) Inflammation
- D) Opsonization
C
44
- Which cells play a role in both phagocytosis and antigen presentation?
- A) Red blood cells
- B) Dendritic cells
- C) Platelets
- D) Eosinophils
B
45
- What process involves neutrophils clinging to the walls of capillaries in the injured area?
- A) Chemotaxis
- B) Margination
- C) Diapedesis
- D) Adherence
B
46
- Which immune cells are the primary responders during the initial phase of inflammation?
- A) Lymphocytes
- B) Eosinophils
- C) Basophils
- D) Neutrophils
D
47
- What effect does fever have on the liver and spleen?
- A) Increases blood flow
- B) Reserves iron
- C) Produces antibodies
- D) Decreases metabolism
B
48
- Which immune cells are involved in the body's response to parasitic worms?
- A) Neutrophils
- B) Eosinophils
- C) Monocytes
- D) Basophils
B
49
- What is the role of prostaglandins in inflammation?
- A) Cause vasodilation
- B) Intensify the effects of kinins
- C) Produce antibodies
- D) Decrease permeability of blood vessels
B
50
- Which cytokine is primarily responsible for fever induction?
- A) Interleukin-1 (IL-1)
- B) Tumor necrosis factor (TNF)
- C) Interleukin-6 (IL-6)
- D) Interferon-gamma (IFN-γ)
A
51
- What stimulates lectin production in the liver?
- A) Antibodies
- B) Cytokines
- C) Prostaglandins
- D) Histamines
B
52
- What does Mannose-binding lectin (MBL) bind to?
- A) Lipopolysaccharides
- B) Peptidoglycan
- C) Mannose
- D) Glycogen
C
53
- Which proteins are activated by MBL in the lectin pathway?
- A) C1 and C3
- B) C2 and C4
- C) C3 and C5
- D) B and D
B
54
- What is the result of C2a and C4b activation in the lectin pathway?
- A) Formation of C1 complex
- B) Activation of C3
- C) Production of antibodies
- D) Release of cytokines
B