Why are there no gram-positive archaea species, but there are gram-positive bacteria species? a. archaea lack peptidoglycan b. archaea lack chitin c. archaea do not have a cell wall d. archaea do not have a cell membrane

 A. Archaea lack peptidoglycan.

Species of bacteria are named gram-positive because of their positive respond towards gram staining technique. These bacteria retain the crystal violet dye and are colored pink or purple because of the presence of thick layer of peptidoglycan in their cell walls, whereas the gram-negative bacteria has thin layer of peptidoglycan hence, cannot retain the stain of the dye. Archaea species do not possess peptidoglycan in their cell wall, therefore will give negative response to gram staining technique, hence, there are no gram-positive Archaea species.  

a is correct because i just took the test

protein synthesis is an example of feedback mechanism which in homeostasis

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