Hi. You have not shown the sections this question refers to, nor have you provided more information about those sections. This makes it difficult for your question to be answered. However, I will try to help you as best I can.
Generally speaking, we can consider that there was no growth of bacterial colonies in sections 2 and 3, because, for some reason, the bacteria was not inoculated in sections 2 and 3. What could also have happened, is that the bacteria in the sections 2 and 3 were eliminated, but the bacteria from section 1 managed to survive and form colonies.
Another possibility is that after inoculating the bacteria in section 1, you didn't handle the bacteria correctly in the other sections, leaving that bacteria to dry out and die.
Finally, the culture media in sections 2 and 3 could be inappropriate for bacteria to develop and form colonies.
Answer:
Rough endoplasmic reticulum and Mitochondria.
Explanation:
Disulfide bonds are known as covalent bonds. They are formed by the oxidation of 2 cysteines and these bonds can provide stability to proteins. These bonds mainly formed in intermembrane space of mitochondria and cellular compartments outside the cytoplasm endoplasmic reticulum. Both of these organelles present in an oxidation state providing an atmosphere for disulfide bond formation.
Cytoplasm and Nuclei mostly exit in reducing state because of the existence of disulfide reductase which is reducing the disulfide bonds between the cysteine residue to thiolate state. So, the disulfide bond formation will not happen.