The assumption here is one of cells reaching (near) confluence and requiring passage into fresh media at lower cell density. For tumor samples, some passage may be necessary to reduce numbers of unwanted cells (blood, fibroblast, etc.) that typically come along for ride when tissue is extracted.Yes, cells could be different after too much growth-especially tumor and tumor-derived cells.ADD COMMENT â¢ link written 5.0 years ago by Larry_Parnell â¦ 15k 1 Also AFAIK, this is the correct definition of passage. little off-topic, but hopefully someone will be able to help. I don't understand what low-passage means in this context. Example usage: 34 primary tumours and eight tumour-derived low passage cell lines were analyzed.
Fluorine is the lightest. Halogens are Group 17 or VII/VIIA of the periodic table just look at the topmost element in that group which is Fluorine (Y).
Rating Newest Oldest. Best Answer: The Least reactive elements are the noble gases: Helium, Neon, Argon, Krypton, Xenon, and Radon. The Most reactive elements are the halogens in group XIIA. Source(s): SJohnson Â· 7 years ago.