I stain an unknown acid with purple dye. Later, you find the cell in two organelles. What are they?

I am guessing that one of them is lysosomes, because they break down unwanted elements. What would the second one be? Mitochondria?

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    $\begingroup$ Take a look at this. $\endgroup$ – Tyto alba Feb 13 '17 at 11:49
  • $\begingroup$ @SanjuktaGhosh So my answer of lysosomes and mitochondria is correct? $\endgroup$ – suomynonA Feb 13 '17 at 16:50
  • $\begingroup$ I think the acid / base terminology is confusing in histology. In my understanding, this is not about pH, it's about charge. "Acidic" stains are deprotonated, and therefore negatively charged molecules, and so they are attracted to positively charged structures. Most proteins are positively charged, so protein-rich structures tend to be stained, while nucleic acids (which are negatively charged) are not. $\endgroup$ – Roland Feb 14 '17 at 7:12
  • $\begingroup$ It is about pH in the sense that acidic dyes will be deprotonated and negatively charged at neutral pH. If the pH is lowered below the pKa of the dye, it will become neutral. $\endgroup$ – canadianer Mar 16 '17 at 3:56

The principle of staining works in such a way that acidic dyes stain the complementary basic components of the cell hence acidic dye rather than staining lysosome which is acidic will stain the relatively basic components of the cell.

  • $\begingroup$ What are complementary basic components? Specifically the complementary aspect. $\endgroup$ – user29734 Feb 13 '17 at 18:55
  • $\begingroup$ So it stains the nucleus and ribosomes? $\endgroup$ – suomynonA Feb 13 '17 at 23:57
  • $\begingroup$ Hi. I am not sure of basicity of some cell organelles. Hence I have provided how staining works because I saw wrong answers; it definitely does not statin nucleus because nucleic acids are acidic in nature. $\endgroup$ – Harsimran kaur Feb 14 '17 at 3:41

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