What do we call the area of Earth, from the top of the highest mountain
to the bottom of the ocean, in which
all life exists?
A. atmosphere
B. life bubble
C. biosphere

a- all cells come from pre-existing cells

during the process of dna replication, brdu can replace thymidine and incorporate into the newly synthesized dna, cell proliferation thus can be reflected in the extent of brdu incorporation.

i might be wrong but i think its a. let me know if i’m right and have a good rest of your day!