I do not have any eductatin in biology, I am a mathematician. However I am reading a book in data science, and am trying to understad an example involving, DNA, mRNA and genes.

From what I understand we have these concepts:

DNA: This is the double helix molecule that makes up our genetic code. The helix is long and consists of a long code, and the code is made up of four molcules and the order in which the molecules occur is the code

Gene: This is different parts of the DNA.

RNA: This is similar to the DNA, but is a single helix. It also consists of four molecules, but one molecule is different from the DNA.

The relevant text is this:

Question:

The author want to measure the amount of genes in a cell by measuring the amount of RNA in that gene. However a gene is something that is in DNA? So by this logic something that is in the DNA consists of RNA, but as I noted above, RNA and DNA are built up of 4 molecules, but one differ, so how can this be?

I do not have any eductatin in biology, I am a mathematician. However I am reading a book in data science, and am trying to understad an example involving, DNA, mRNA and genes.

From what I understand we have these concepts:

DNA: This is the double helix molecule that makes up our genetic code. The helix is long and consists of a long code, and the code is made up of four molcules and the order in which the molecules occur is the code

Gene: This is different parts of the DNA.

RNA: This is similar to the DNA, but is a single helix. It also consists of four molecules, but one molecule is different from the DNA.

The relevant text is this:

Question:

The author want to measure the amount of genes in a cell by measuring the amount of RNA in that gene? However a gene is something that is in DNA? So by this logic something that is in the DNA consists of RNA, but as I noted above, RNA and DNA are built up of 4 molecules, but one differ, so how can this be?