The looping of the template for the lagging strand enables a dimeric DNA polymerase III holoenzyme at the replication fork to synthesize both daughter strands. (Courtesy of A. Kornberg. From L. Stryer, Biochemistry, 4th ed.he 3â²âââ5â² exonuclease action of DNA polymerase III. Note that this exonuclease activity takes place at the 3â² end of the growing strand (and is therefore 3â²âââ5â²). The coordination of exonuclease activity with strand growth helps to explain why replication is in the 5â²âââ3â² direction.
McAllen is the twenty-first most populous city in Texas and the largest city in Hidalgo County, Texas. It is located at the southern tip of Texas in the Rio Grande Valley (not a geographical valley) and is part of the Southern United States.
Geography. McAllen is located at 26Â°12â²59â³N 98Â°14â²11â³W / 26.21639Â°N 98.23639Â°W / 26.21639; -98.23639 (26.216263, -98.236385) . According to the United States Census Bureau, the city has a total area of 46.3 square miles (120 km 2).