A few questions about genetics

[splash.of.colour]

hi all, im really confused at the moment i terms of genetics so if you could help that would be great

i know each chromosome contains one molecule of double stranded DNA. In an individual, is the base sequence of this molecule the same in all of their chromosomes and cells? or do different chromosomes have different base sequences of DNA?

[Jenny_2108]

hi all, im really confused at the moment i terms of genetics so if you could help that would be great

i know each chromosome contains one molecule of double stranded DNA. In an individual, is the base sequence of this molecule the same in all of their chromosomes and cells? or do different chromosomes have different base sequences of DNA?

Each chromosome only contains double stranded DNA before they start cell division and during prophase, metaphase (mitosis) or PMAT I+prophase, metaphase II (meiosis). Normally, it apprears as a single stranded DNA but in the karyotype, you see it as homologous pairs with double stranded as during cell division, chromosomes condense and visible under the microscopy.

In an individual, the base sequence of this molecule can be different in their chromosomes because it depends on types of protein synthesis, RNA production and the function of the genes. Different chromosomes also have different size, length and position of centromeres, so they consist of different number of base pairs, it means possibly different base sequences as well.

This is my understanding. Hope this helps!

[splash.of.colour]

okay thankyouuuu so much 

One more thing, the genome of a cell refers to the complete set of genetic material within a HAPLOID cell right? Not a diploid cell?

[Jenny_2108]

okay thankyouuuu so much 

One more thing, the genome of a cell refers to the complete set of genetic material within a HAPLOID cell right? Not a diploid cell?

The genome of eukaryotes is the total genetic material contained in a haploid set of chromosomes in the nucleus of every cell except red blood cells. They exist as two copies in chromosomes except in gametes and red blood cells.