What is the structure labeled e in the diagram below?

a . nucleus

b. cytoplasm

c. ribosome

d. mitochondrion

b: cytoplasm

ignore this bit it allows me to summit my question

meteorologists would compare a new weather map with one 24 h old to see how fast a front is moving.

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.