The two strands of DNA in a double helix are ______________.

Question 20 : The restriction map of the plasmid pSC48 is presented below. The numbers in parentheses correspond to the position of the respective restriction site with respect to position (0). (0) BamHI ЕcoRI (4640) (620) PSC48 5200 pb BamHI (1130) Smal ЕcoRI (3420) (1350) The plasmid has been digested by one or several restriction enzyme(s). The digestion products have been analysed by agarose gel electrophorese. (see figure below). 1 2 10,000 8,000 6,000 5,000 4,000 3,000 2,500 –2,000 - 1,500 -1,000 -750 - 500 -250 1. Digestion products 2. Size marker base pairs Which restrcition enzyme(s) have been used for the digestion? (Indicate the right answer) А- ЕсoRI. B- EcoRI/BamHI. C- EcoRI/Smal. D- BamHI. E- Smal. | |

In the structure of DNA, the "double helix" is composed of ________________.   Question 7 options:   two (2) chromosomes that are twisted around each other   two (2) strands of linked nucleotides that are twisted around each other   four (4) strands of linked nucleotides that are bound by phosphate groups   two (2) strands of linked nucleotides that fold back and forth like an accordion   four (4) strands of linked nucleotides that are bound by sugar groups

question #45 please