L2 Innate Response

b

What is the body's ability to prevent and fight off disease or infection called?

• a) Antigenicity

• b) Immunity (Resistance)

• c) Hypersensitivity

• d) Chemotaxis

c

Which of the following is a primary goal of the innate immune response?

• a) Generating immunological memory

• b) Producing specific antibodies

• c) Phagocytosis and tissue healing while minimizing host tissue damage

• d) Responding differently to repeated exposures

c

Which water-insoluble protein localized on the apical membrane provides structural resistance and promotes epidermal cell shedding?

• a) Psoriasin

• b) Sebum

• c) Keratin

• d) Fibrinogen

c

What is the skin protein with antimicrobial properties involved in cutaneous defense and cell growth regulation?

• a) Lactic Acid

• b) Lysozyme

• c) Psoriasin

• d) Haptoglobin

b

Which enzyme found in perspiration cleaves bacterial peptidoglycan bonds?

• a) Ceruloplasmin

• b) Lysozyme

• c) Elastase

• d) C3 convertase

c

What Toll-Like Receptor (TLR) specifically recognizes Lipopolysaccharide (LPS)?

• a) TLR1

• b) TLR2

• c) TLR4

• d) TLR5

b

Which TLR recognizes Flagellin from flagellated bacteria?

• a) TLR3

• b) TLR5

• c) TLR7

• d) TLR9

a

Endosomal TLRs (3, 7, 8, 9) are primarily localized within intracellular endosomes to detect what?

• a) Nucleic acids (viral dsRNA/ssRNA and bacterial/viral dsDNA)

• b) Extracellular bacterial surface structures

• c) Peptidoglycan and Zymosan

• d) Lipopolysaccharide (LPS)

b

Which cytosolic sensors detect viral RNA within infected host cells and induce the secretion of Type I Interferons?

• a) Toll-Like Receptors (TLRs)

• b) Retinoic Acid-Inducible Gene-I-Like Receptors (RLRs)

• c) Nucleotide-Binding Oligomerization Domain-Like Receptors (NLRs)

• d) Pattern Recognition Receptors (PRRs)

b

Which cytosolic sensors assemble into multiprotein complexes called inflammasomes?

• a) RLRs

• b) NLRs

• c) TLRs

• d) PAMPs

c

Peptidoglycan (PDG) is a Pathogen-Associated Molecular Pattern (PAMP) found primarily in which of the following?

• a) Yeast and fungi cell walls

• b) Gram-negative bacterial outer membranes

• c) Gram-positive bacteria cell walls

• d) Viral envelopes

a

Zymosan is a cell wall component recognized as a PAMP in which organisms?

• a) Yeast and fungi

• b) Gram-negative bacteria

• c) RNA viruses

• d) Mycobacteria

b

What is the structural subclass of cytokines that function explicitly as chemical attractants to direct leukocyte migration?

• a) Interferons

• b) Chemokines

• c) Opsonins

• d) Anaphylatoxins

b

Acute-Phase Reactants (APRs) are serum proteins whose concentrations change significantly by what percentage in response to acute inflammation?

• a) >10%

• b) >25%

• c) >50%

• d) >75%

c

According to the high-yield rule, which of the following are the ONLY negative Acute-Phase Reactants (APRs)?

• a) C-Reactive Protein and Serum Amyloid A

• b) Fibrinogen and Haptoglobin

• c) Albumin and Transferrin

• d) Ceruloplasmin and a1-Antitrypsin

d

What is the normal range (NR) for C-Reactive Protein (CRP)?

• a) 5-8 µg/mL

• b) 20-40 mg/dL

• c) 40-290 mg/dL

• d) 0.47-1.34 mg/L

a

Which Acute-Phase Reactant acts as an antioxidant by irreversibly binding free hemoglobin released during intravascular hemolysis?

• a) Haptoglobin

• b) Fibrinogen

• c) Ceruloplasmin

• d) a1-Antitrypsin

b

Which copper-transporting protein oxidizes toxic ferrous iron into ferric iron for safe transferrin binding?

• a) Serum Amyloid A (SAA)

• b) Ceruloplasmin

• c) C-Reactive Protein (CRP)

• d) Haptoglobin

c

In serology, what term is defined as the reciprocal of the highest serum dilution that demonstrates a positive reaction?

• a) Acute phase

• b) Serial dilution

• c) Titer

• d) Detection threshold

b

What is the central and most abundant complement protein in the complement cascade?

• a) C1

• b) C3

• c) C5

• d) C9

b

Which fragment of the complement system acts as a major opsonin that tags microbes for phagocytosis?

• a) C3a

• b) C3b

• c) C5a

• d) C5b

c

What term refers to a bioactive peptide fragment (e.g., C3a, C5a) that triggers degranulation of mast cells and basophils?

• a) Chemotaxin

• b) Opsonin

• c) Anaphylatoxin

• d) Pyrogen

b

Which state of iron is highly soluble, dangerously reactive, and participates in Fenton reactions?

• a) Ferric Iron (Fe 3+)

• b) Ferrous Iron (Fe 2+)

• c) Transferrin-bound Iron

• d) Ferritin-stored Iron

b

Which cardinal sign of inflammation is caused by localized hyperthermia from increased blood flow (vasodilation)?

• a) Dolor (Pain)

• b) Calor (Heat)

• c) Rubor (Redness)

• d) Tumor (Swelling)

c

What is the specific term for the step in inflammation where leukocytes marginate, roll, and squeeze through vessel walls?

• a) Vasodilation

• b) Plasma Leakage

• c) Diapedesis

• d) Chemotaxis

b

During phagocytosis, what is the membrane-bound cytoplasmic vacuole containing the internalized microbe called?

• a) Phagolysosome

• b) Phagosome

• c) Pseudopod

• d) Endosome

c

The oxygen-dependent pathway (oxidative burst) of microbicidal killing is activated by which of the following?

• a) Phagolysosome membrane depolarization

• b) Influx of H+ and K+ ions

• c) NADPH Oxidase activation

• d) Activation of Defensins

b

Under the "Missing Self Hypothesis," Natural Killer (NK) cells are triggered to attack target cells that lack which surface markers?

• a) Antigen-specific receptors

• b) MHC Class I markers

• c) FcyRIII (CD16) receptors

• d) Toll-Like Receptors

c

Pyrogens (such as IL-1, TNF-a, and IL-6) cause fever by resetting the thermostat in which part of the brain?

• a) Thalamus

• b) Hippocampus

• c) Hypothalamus

• d) Pituitary gland

b

Pyrogens (such as IL-1, TNF-a, and IL-6) cause fever by resetting the thermostat in which part of the brain?

• a) Thalamus

• b) Hippocampus

• c) Hypothalamus

• d) Pituitary gland