Unsure about definition of “n” and “C” values in mitosis

Unsure about definition of “n” and “C” values in mitosis

I am preparing for a Biology exam and Im reviewing the n and C notation used in mitosis. My professor said that when the cell replicates its DNA in S phase of mitosis, we get twice the amount C of DNA, but we still have the same number of chromosomes. Does this mean that if the replicated chromosomes were to split apart from their centromeres, we would have a 4n cell so a cell with 4 sets of chromosomes At the same time, my intuitive response sort of says, well, theyre replicated, so theyre exactly the same, so youd technically have 2 sets, not 4 right.

While Ive not heard of the C notation previously, n is common notation that indicates the ploidy of a cell. The n refers to the number of unique chromosomes within a cell. Eukaryotic cells are generally diploid, or 2n. The multiplying number - 2 in the diploid case - refers to the number of versions of each unique chromosome. For example, humans are diploids 2n. We have 23 unique chromosomes 22 regular chromosomes and 1 sex chromosome, but we have 2 variants of each chromosome to give us a total of 223 46 chromosomes. Prior to S phase, diploid cells contain 2n content maybe content refers to C notation of DNA. During S phase the cell duplicates its DNA content generating 2 sets of 2n chromosomes 2 copies of 46 chromosomes for a total of 92 chromosomes in the human case. You are correct in that it is 2 sets of 2n rather than 4n, since the convention would indicate 4n as a tetraploid many types of plants are in fact tetraploid, https:en.wikipedia.orgwikiPolyploid. At the end of the mitotic cell cycle, cell division functions to separate the 2 sets of 2n chromosomes into two distinct cells, each containing 2n chromosomes. If all 4 chromosomes separated from each other and the cell was able to divide into quarters rather than halves, that would yield 4 1n cells. This latter idea is what occurs in meiosis.