Which best describes a centromere?
Which best describes a centromere? A.sister chromosomes that are held together by a chromatid B.paired chromosomes that have genes arranged in the same order C.the center of a chromosome D.the material that makes up a chromosome
What will happen if one has less or more chromosomes inside his or her body?
Most of the time, having the wrong number of chromosomes means you don't stay alive long enough to be born. There are only four ways to have an extra chromosome and live to adulthood:1) Down syndrome, in which people have an extra copy of Chromosome 21.2) Klinefelter syndrome, in which men have an extra X chromosome, making them XXY.3) XYY syndrome, which might not be a syndrome, really. From what I understand, most XYY men are pretty similar to XY men.4) Triple X syndrome, in which women are XXX. There are two ways to have an extra chromosome and have a chance of making it through fetal development, though you probably won't live much longer than that:1) Edwards syndrome 2) Patau syndrome And there's only one way to be missing a chromosome and live to adulthood:http://en.wikipedia.org/wiki/Tur...For more information on how anyone ends up with anything other than the usual 46 chromosomes, see: http://en.wikipedia.org/wiki/Non...
Are chromotids ONLY connected at the centromere?
It depends on how long the centromere is; it is different lengths for different species, running the entire length of a chromosome (holocentric chromosomes) in many species. But for humans, and the typical X shaped chromosomes shown in most diagrams, the sister chromatids are joined at a restricted region called the centromere, which is but a fraction of the length of the entire chromosome.
How does an acentric and a dicentric chromosomes look like? What are they?
Acentric chromosomes lack centromeres, because the centromere region has been translocated onto another chromosome. You can learn a lot about how they work and look in this very detailed paper if you need to: http://pingu.salk.edu/~wahl/Tkanda_JCBio... Dicentric chromosomes have two centromeres. You can see how they form and what they might look like here: http://mti-n.mti.uni-jena.de/~huwww/MOL_...