Question

Which of the following is true about cancer cells?
A: they are not inhibited by density when growing in a cell culture
B: when they stop dividing, it is at random points in the cell cycle
C: they have by-passed from cell cycle controls
D: B and C are true
E: all of the above


I think that it is D, but I am not sure

Answer 1

B and C are most definitely both true.

One of the cytologically interesting facts about cells - normal, healthy cells - is that they take their cues from the cells surrounding them. If they sense there are a lot of cells in the immediate area, they figure out - through a series of biochemical signalling pathways that all suppress cell division - that there are enough of their particular kind of cell already. So they don't divide.

Cancer cells have lost this ability - they go on dividing, even to the extent of crowding themselves to the edges of the culture dish and forming layers on top of each other. So even though it is not so readily apparent as B and C, A is true too.

Answer 2

i will go for C..........im not sure about B .. :)