This might sound stupid for all of you experienced users of mechanical pencils but...... first time user of a mechanical pencil(Pentel P205)-I have just used up my first piece of lead and need to refill it. BUT I can't figure it out. The lead will not stay in the opening.
Gram positive bacteria have a single thick cell wall made of peptidoglycan (50-90% of cell wall). This thick wall stains purple and remains purple throughout the gram staining test. Gram negative bacteria have a thinner layer of peptidoglycan (10% of cell wall), and an additional outer membrane which contains lipids.The outer membrane of gram negative bacteria will stain purple also but it falls off during the gram stain test. Its 2nd wall is what gets stained pink.he trick to remembering the difference between gram positive and gram negative bacteria is to first understand where their naming convention comes from. I have an article follow by a mini game to teach you the difference between gram positive and gram negative bacteria.
Gram-positive and Gram-negative bacteria stain differently because of fundamental differences in the structure of their cell walls. The bacterial cell wall serves to give the organism its size and shape as well as to prevent osmotic lysis. The material in the bacterial cell wall which confers rigidity is peptidoglycan.