Answer:
In gram staining, 95% ethanol is used to destain the gram-negative bacteria but gram-positive bacteria do not get destain because peptidoglycan layer in gram-positive cell wall does not allow crystal violet- iodine complex to come out of the cell wall.
Gram-negative bacteria do not have peptidoglycan cell wall and so crystal violet comes out of the cell wall by using 95% ethanol because ethanol dissolves the lipopolysaccharide membrane of gram-negative bacteria and allow the dye to leak out.
Therefore if I forgot to apply 95% ethanol than crystal violet dye will not come out of the lipopolysaccharide cell wall of gram-negative bacteria and it will appear violet under the microscope.
Is this dealing with mitosis?
" Gametophyte, Secondary. "
Answer:
The correct answer is: geography and UV radiation.
Explanation:
Skin variation occurred thanks to evolution, and was driven as a consequence of the geographical location of different populations of humans.
The humans that lived in hot and sunny places, closer to the equator, where much more exposed to the sun's ultraviolet radiation. In order to survive the amount of UV lights that they were exposed to, new humans in those regions were being born with a darker skin tone, which was rich in melanin (a brown pigment that protects us from the sun radiation).
Contrary to these humans that lived in the tropical areas, the humans that populated the areas that were closer to the poles, developed much lighter skin as a result of lower amounts of melanin in their skin. Since sun exposure in the poles is very limited, humans needed to receive as much as they could for the production of Vitamin D, and thus, their skins got lighter and less protected.
Answer: your answer is C
Explanation: I had the same problem
