Basic Science and Immunology Flashcards
7 cards from real ABD practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Basic Science and Immunology flashcards as text
Melanin is synthesized from which amino acid precursor via the enzyme tyrosinase?
Answer: Tyrosine
Tyrosinase converts tyrosine to DOPA and then dopaquinone in melanogenesis.
Which cell adhesion structure connects adjacent keratinocytes and is targeted by autoantibodies in pemphigus vulgaris?
Answer: Desmosome
Desmosomes (via desmoglein 3) are disrupted in pemphigus vulgaris causing acantholysis.
Type VII collagen, defective in dystrophic epidermolysis bullosa, forms which structure?
Answer: Anchoring fibrils
Type VII collagen forms anchoring fibrils that attach the lamina densa to dermis.
The complement pathway activated directly by antigen-antibody complexes begins with which component?
Answer: C1
The classical pathway is initiated by C1 binding to antibody-antigen complexes.
Which vitamin is synthesized in the skin from 7-dehydrocholesterol upon UVB exposure?
Answer: Vitamin D
UVB converts 7-dehydrocholesterol to previtamin D3 in the epidermis.
Mast cell degranulation in urticaria releases which principal preformed mediator responsible for the wheal?
Answer: Histamine
Histamine is the key preformed mediator stored in mast cell granules driving urticaria.
The stratum corneum barrier lipids are delivered to the extracellular space by which keratinocyte organelle?
Answer: Lamellar (Odland) body
Lamellar bodies secrete lipids forming the intercellular barrier of the stratum corneum.