Answer and Explanation:
The lymph node are the sites for the formation of lymphocytes and monocytes. These are concerned with antibody formation and phagocytosis of foreign materials respectively. In the lymph nodes, bacteria and other harmful materials are removed from lymph.
Diatoms contain chloroplasts that have four membranes. These four membranes are evidence of secondary endosymbiosis (Option c).
<h3>What is secondary endosymbiosis?</h3>
Secondary endosymbiosis is a hypothesis used to explain why diatom chloroplasts have four membranes.
According to this hypothesis, diatoms received different genes from distinct photosynthetic and non-photosynthetic ancestors.
The acquisition of genes of different ancestors led to diatoms having chloroplasts with four membranes.
Learn more about the endosymbiosis hypothesis here:
brainly.com/question/2957447
<span>#1) With reference to the role of oncogenes, explain how the normal controls over the cell cycle can be lost.
Answer: The way that cell cycle can be lost is by going through changes in the activity of cell cycle regulators. Cancer causes different types of mutations. There are two types of cell cycle regulators that can promote the development of cancer:
-Positive Regulators that can be over activated (become oncogenic).
-Negative Regulators (tumor suppressors) which can be inactivated.
I hope it helps, Regards. <span /><span>
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