Question

White blood cells called B cells produce proteins that can be used for the treatment of certain illnesses. However, these B cells do not live for very long on their own. To keep the B cells growing for a long time in laboratories, scientists fuse the B cells with cancer cells (fused B-cancer cells) that do grow for a very long time. The particular cancer cells used for the fusion are treated with chemicals that make them unable to produce the nitrogenous bases adenine and guanine, but the B cells with which they are fused do produce these nitrogenous bases. The scientists grow the large fused B-cancer cells in a growth medium that contains necessary nutrients for the cells and includes a source of carbon. 1. Make a claim about the most immediate effect on the fused B-cancer cells if the fused cells are transferred to a growth medium that lacks a source of nitrogen.

2. Provide reasoning with evidence-based on the composition of biological macromolecules to support your claim.

Answer 1

1. The cells will encounter with nitrogen stress, will cease the production of monoclonal antibodies and will die eventually if the fused cells are transferred to a growth medium, which is devoid of nitrogen. The amino acids and the DNA, all comprise nitrogen as a basic building block.

In the case of the nitrogen is not present, the replication of DNA will get influenced, thus, influencing the production of proteins due to defective amino acids that will eventually result in the death of cell.

2. Nitrogen is present in the biological macromolecules like amino acids and DNA. The composition of an amino acid is not complete in the absence of nitrogen. In the case of DNA, the bases, that is, the pyrimidines and purines all comprise nitrogen in their fundamental composition.

The amino acids in combination produce proteins, the antibodies are proteins. Thus, if the formation of amino acids does not take place, the formation of monoclonal antibodies will also get ceased. Also, for the replication of DNA and transcription process, there are requirements of dNTPs and rNTPs, which also constitute nitrogen fundamentally. Hence, in the absence of nitrogen the cell will die.