QUESTION:
This question is incomplete, the completed version is given below:
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 macro molecules to support your claim.
ANSWER
1. CLAIM: If the fused cells are transferred to a growth medium that lacks a source of nitrogen, THE FUSED CELLS WILL STOP PRODUCING PROTEIN AND EVENTUALLY DIE.
The white blood cells that are used in the experiment described in the question naturally have short life span. Their life span was extended as a result of the cancerous cells that were fused to them and also because of the composition of the growth medium that was used for their reproduction.
2. The growth medium used in the experiment served as a source of nitrogen and carbon for the white blood cells.
White blood cells are made up of nucleus (that contain DNA) and RNA, so they are able to synthesize protein.
For the cancerous cells to continue multiplying, they need a source of nitrogen to produce the nitrogenous bases (adenine and guanine) which they lack. The nitrogenous bases are used to synthesize DNA molecules. With DNA molecule in place, the production of protein can continue unhindered and the fused B cancer cell will continue to live and synthesize protein.
For the production of the fused cancer cells to continue, source of nitrogen must be present in the growth medium; in a situation where the growth medium lack the necessary nitrogenous bases (needed to manufacture DNA), the fused B cancer cells will stop synthesizing protein and die out.
