The immune system monitor continuously the lymphocyte cell levels in order to ensure the protection of the body. These cells are a type of white blood cells that are important in determining the specificity of the response of the body to foreign substances and infectious microorganisms. This group of cells include the T cells, B cells and the natural killer cells. These are produced in the bone marrow and are transported to the lymphatic systems like the thymus, spleen and the lymph nodes. The NK cells function in cytotoxic innate immunity or the cell-mediated ones. T-cells would function by connecting to virus antigens on the outside of a cell that is infected while B-cells would connect to the virus directly in its surface.
Answer:Chromatic observation
Explanation:
In eukaryotic cells the DNA can be found in the nucleus mainly. so DNA replication takes place in the nucleus during the S phase of the cell cycle.
Also in eukaryotic cells there are mitochondria and chloroplasts (plants) and these have circular DNA and they also get replicated (according to their own mechanism).
Prokaryotic cells don't contain a nucleus. They do not contain DNA in the cytoplasm and thus the DNA replication will take place here.
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