Answer the following about mechanisms by which immune cells kill pathogens, for 10 points each.
[10e] Macrophages digest bacteria in a phagosome (“FAY-goh-soam”) where this quantity is low enough to denature proteins. Most bacteria prefer this quantity to be slightly alkaline.
ANSWER: pH [or power of hydrogen; prompt on acidity]
[10m] Neutrophils kill phagocytosed bacteria by reacting this compound with oxygen to generate free radicals. Cells use this electron carrier for anabolic reactions like photosynthesis, but prefer a derivative with one fewer phosphate for catabolism.
ANSWER: NADPH [or NADP+; or nicotinamide adenine dinucleotide phosphate; reject “NAD” or “NADH” or “nicotinamide adenine dinucleotide”]
[10h] Cytotoxic T cells kill their targets by secreting this protein, which pokes holes in target cell membranes to let in pro-apoptotic proteases called granzymes.
ANSWER: perforin
<Adam Silverman, Science - Biology> ~20885~ <Editor: Adam Silverman>