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Ethidium homodimer is responsible for the red color observed. How is it able to cross an intact
plasma membrane?
a. binds to calcein
b. it can't
c. esterase
d. binds to flippase
Solution
1. Calcein, is a green membrane permeable flourescent dye that is hydrolyzed by esterase,
causing it to become negatively charged and be retained in the cytoplasm, along with ethidium
homodimer, a positively charged flourecent nucleic acid stain that cannot cross intact cell
membranes.

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Ethidium homodimer is responsible for the red color observed. How is.pdf

  • 1. Ethidium homodimer is responsible for the red color observed. How is it able to cross an intact plasma membrane? a. binds to calcein b. it can't c. esterase d. binds to flippase Solution 1. Calcein, is a green membrane permeable flourescent dye that is hydrolyzed by esterase, causing it to become negatively charged and be retained in the cytoplasm, along with ethidium homodimer, a positively charged flourecent nucleic acid stain that cannot cross intact cell membranes.