Question

Do you think there is an upper limit to chromosome number? Explain.

Answer 1

There is an upper limit to chromosome number due to the essential balance of gene expression for normal development. Chromosome number and DNA amount are not directly correlated, as gene density can vary. Improved laboratory techniques can facilitate more accurate DNA quantification.

Step-by-step explanation:

When considering if there is an upper limit to chromosome number, it's important to understand that chromosomes carry numerous genes, and any significant alteration can severely impact an organism's development. In humans, most embryos with extra chromosomes do not survive, with the exception of some cases like Trisomy 21, which leads to Down syndrome. The critical balance of chromosome and gene expression is why too many or too few chromosomes typically result in inviability or serious developmental issues.

Chromosome number does not necessarily correlate to DNA amount because the size of chromosomes and the density of genes can vary widely across different organisms. In a laboratory setting, comparisons can be made more accurate by quantifying DNA content through techniques such as DNA sequencing or fluorescence-based quantification, rather than simply counting chromosome numbers.

The one chromosome differing between genetic males and females is the Y chromosome; males have one X and one Y, while females have two X chromosomes. Only females have Barr bodies because they inactivate one of their two X chromosomes to prevent gene dosage imbalance, a process not necessary in males with only one X chromosome.

Answer 2

There is a upper limit to chromosome number. The upper limit is caused by incomplete segregation of sister chromatids and trimming of the long arms.

Step-by-step explanation:

There is a practical limit to the number of chromosomes related to how they can line up in homologous pairs for meiosis in sexually reproducing organisms.

They have a practical limit to number of spindle fibers that you can have in the cell during mitosis.

There is a fern with more than thousand chromosomes. The micronuclei represent loss of DNA from the genome and are lost outright through further cell divisions.