Rani Coleman Possibly if I get chance...new mitosis vid just gone up. DNA Hybridisation in a nutshell.... - Get DNA from two species - Radioactively label DNA from Species A -Heat both to separate strands -Mix strands from both species and cool - Hydrogen bonds form...more = stronger -Heat hybrid strand...the higher the temp before breaking..the more hydrogen bonds have formed, therefore the more complementary bases...therefore closely related. done :)
Hi, could you just double check to see if what I understand is right? Video was really helpful, thank you! Before Meiosis I, there's a paternal chromosome= I, and a maternal chromosome= I. These are a homologous pair and because they code for the same genes (although they may have different alleles). Before Meiosis I, both replicate themselves, so the maternal goes from an I to X shape so what was originally a single chromosome is now 1 of 2 chromatids that forms a chromosome (now X shaped because the single has replicated)...is this right? Is I shape a chromosome and when it replicates it becomes a chromatid? then the paternal and maternal homologous pair align XX and may swap DNA (genetic recombination) and then are randomly separated into daughter cells according the way they line up due to independent assortment?
Bethan Mcginley In this video I have not included the stage where the DNA replicates...this is explained in my mitosis vid. You are correct that the maternal and paternal chromosomes are homologous and your definition is correct. The chromosome (X shape) consists of two sister chromatids (I shapes) that have duplicated during mitosis. I hope that helps?
Great video, but ne thing that always baffles me is that how come at the end when you were explaining Independent Segregation with that image, there were more chromosomes that the one you previously used? Since now there's a diploid cell than haploid? Please explain
For the independent segregation explanation to work, you need more than one chromosome to use as an example. If you look carefully at the image, the original cell has 4 chromosomes (diploid) and the gametes end up with 2 chromosomes (haploid).
Hi, do we not need to learn each stage in detail (prophase,late prophase, metaphase, anaphase, telophase) . I'm a private candidate and a bit confused. Thanks
