For 10 points, name these paired structures consisting of DNA that can come in X and Y varieties.
Two of these structures fuse together in a phenomenon named for William Robertson, and they can form a fibrous corona when initiated by the spindle checkpoint. Centimorgans measure the length of these structures, which contain repeating TTAGGG sequences. During prometaphase, kinetochores on the centromeres of these objects attach to microtubules. Prokaryotic plasmids are analogous to these structures, which can undergo aneuploidy as a result of their non-disjunction. Telomerase lengthens the ends of them, and a third copy of one of them structures can result in Down syndrome. For 10 points, name these paired structures consisting of DNA that can come in X and Y varieties.
Two of these structures fuse together in a phenomenon named for William Robertson, and they can form a fibrous corona when initiated by the spindle checkpoint.
chromosomes [accept telomeres before mention; accept specific chromosome numbers/names before “Down syndrome”] &lt;SC/AT&gt;