Scientists call a mature ecosystem a

A.) Climax Community
B.) Secondary Succession
C.) Old growth Forest

as many times as you want

the dna molecules have a negative charge because of the phosphate groups in their sugar-phosphate backbone, so they start moving through the matrix of the gel towards the positive pole. power is turned on and dna fragments migrate through gel (towards the positive electrode).

explanation:

answer; endoplasmic reticulum;