请教两道生化题，非常感谢！！

jiangtao9455UID: 194779

请教两道生化题：

1、A plasmid that has two HindIII sites and two EcoRI sites, was cut with both of the enzymes simultanously for 5hrs at 37.C. The analysis of the restriction enzyme digestion was made on a 1% agarose gel. How many bands would one expect to see on the gel?
a 3       b 4         c 5         d 16          e No bands. Only smears

2、A viral genomic DNA that has two HindIII sites and two EcoRI sites, was cut with both of the enzymes simultanously for 5hrs at 37.C. The analysis of the restriction enzyme digestion was made on a 1% agarose gel. How many bands would one expect to see on the gel?
a 3       b 4         c 5         d 16          e No bands. Only smears

请教解题思路，非常谢谢！！

hans19812002UID: 160177

The answer might be:
1. plasmid is circular DNA. so there are four strands on the gel
2. it depends on whether the viral DNA is circular or linear

[ 本帖最后由 hans19812002 于 2007-10-5 07:19 编辑 ]

jiangtao9455UID: 194779

谢谢楼上，我明白了

AA_workoutUID: 2405812

Viral genomic DNA  shouldn't be circular, maybe I'm wrong, try to find reference

hans19812002UID: 160177

In fact, genomic DNA of Phage lambda is circulized in bactiera

qas168888UID: 2248748

哈哈，lambda，我正想说的～不过感觉题目这么出，就算默认了