The answer is 20. Duplicated chromosome has two sister chromatids, identical copies of the chromosome. These two chromatids are joined at the region called centromere. Therefore, one duplicated chromosome has one centromere and two sister chromatids. If there are 20 duplicated chromosomes in a cell, there will be 20 centromeres.
The biggest airlines flying to United States: American Airlines flights to United States, Delta flights to United States, Southwest Airlines flights to United States. Regions in the USA - United States. Airlines flying to the USA - United States - by city.
United says the new route become the worldâs longest Dreamliner flight and the longest regularly scheduled flight operated by any U.S. carrier. United also will become the only airline to fly nonstop from the United States to Singapore. Flights on the new route will begin June 1.