On Gram stain, mycobacteria appear as:
a. slender, well-stained gram-positive bacilli.
b. poorly stained, beaded, gram-positive ba-cilli.
c. gram-variable to gram-positive bacilli.
d. partially invisible gram-negative bacilli.
B
Because of their cell wall makeup, mycobacteria usually appear as slender, poorly stained, beaded, gram-positive bacilli on Gram stain. Sometimes they appear as "gram-neutral" or "gram-ghosts" by failing to take up either crystal violet or safranin.
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Name two factors that will influence the composition of aquatic communities
What will be an ideal response?
Which 3 are true of dominant and recessive traits?
What will be an ideal response?
Protein folding can be studied using a solution of purified protein and a denaturant (urea), a solvent that interferes with noncovalent interactions. Which of the following is observed after the denaturant is removed from the protein solution?
(a) The polypeptide returns to its original conformation. (b) The polypeptide remains denatured. (c) The polypeptide forms solid aggregates and precipitates out of solution. (d) The polypeptide adopts a new, stable conformation.