Biology 9700 · AS & A Level · Structure of nucleic acids and replication of DNA

Structure of nucleic acids and replication of DNA — practice question

Fig. 3.1 shows a light micrograph of root-tip cells from the garlic plant Allium sativum. The diploid number $(2n)$ is $16$.
(a)[1]

Identify the stage of mitosis visible in cell D.

(b)[2]

Explain why mitosis takes place in a plant such as Allium sativum.

(c(i))[1]

State the haploid number for Allium sativum.

(c(ii))[3]

Explain why a plant such as Allium sativum produces haploid cells.

(d)[5]

DNA replication must happen before cell division. Describe the process of DNA replication.

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