Answer:
Because older cultures of gram-positive bacteria tend to lose their ability to retain crystal-violet in the peptidoglycan of their cell walls and can be confused with gram-negative bacteria.
Explanation:
Gram staining is used to differentiate between two major groups of bacteria. Gram-positive and gram-negative, these bacteria differ in the amount of peptidoglycan in their cell walls. Gram-positive bacteria have a higher amount of peptidoglycan, which absorbs the violet crystal complex used in gram staining, staining them purple/violet. Old cultures of gram-positive bacteria tend to lose the ability to retain the violet crystal and are stained by safranine, staining them red/pink and appear to be gram-negative.
Unfortunately, no, all I know about it is that it causes extreme damage.
found that animals are composed of cells is Theodor Schwann
found that plants are composed of cells is Matthias Schleiden
looked at cork through a compound microscope is Robert Hooke
declared that all living cells can only come from other living cells called living cells "animalcules" is Rudolph Virchow
ANSWER:
Index Fossils can be used to identify a specific period of time
