= Solution
\b[ToxB greatly reduces recognizable <actin cables> and <actin patches>.] Untreated <biological cells> contain concentrated cortical structures, especially in buds, whereas treated <biological cells> show only weak diffuse staining even at ten times the exposure. The disappearance concerns <actin filament> organization and detectable <F-actin>, not necessarily destruction of the <actin> <protein> itself. <actin monomer sequestration> could leave substantial total <actin> present while eliminating most visible <polymer>.
Loss of <actin cables> should impair directed secretory-vesicle delivery and <polarized cell growth>; loss of <actin patches> should impair actin-dependent <endocytosis>. Disruption of the <actomyosin> machinery can also compromise <cytokinesis>. The rounded, poorly polarized appearance is consistent with these effects, but the images do not independently measure secretion, division rate or viability. A <vehicle control> and equal-exposure images are needed for quantitative <fluorescence> comparison; a longer exposure is useful for finding residual structures but prevents direct comparison of the displayed brightnesses.
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