(a)[5]
Complete Table 4.1
(b)[3]
Explain why the growth of roots, such as those of $A.\,cepa$, is carried out by mitosis.
(c)[2]
State two processes, apart from growth, in which mitosis takes part.
Biology 9700 · AS & A Level · Structure of nucleic acids and replication of DNA
Structure of nucleic acids and replication of DNA — practice question
A student prepared thin sections from a root tip of $\textit{Allium cepa}$ and stained them so the chromosomes could be seen. Fig. 4.1 shows a photomicrograph of part of one of these sections. Table 4.1 outlines chromosome behaviour and the changes in the nuclear envelope during a mitotic cell cycle in the root tip of $A.\,cepa$.
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