Answer:
Rocks across the ocean floor have alternating magnetic stripes.
Explanation:
Different types of evidence supported Hess's theory of sea-floor spreading: eruptions of molten material, magnetic stripes in the rock of the ocean floor, and the ages of the rocks themselves. This evidence made scientists take a second look at Wegener's hypothesis of continental drift.
A.<span> Air pollution............................</span>
Answer:
The correct option is : cells containing empty plasmid vectors
Explanation:
The blue-white screen is a technique which involves the rapid identification of the recombinant bacteria in a vector-based molecular cloning experiment. In this method, a DNA ligated vector is inserted in a host cell which is viable for transformation and grown in presence of X-gal.
The cells that are transformed with the vectors having the recombinant DNA produce the white colonies. Whereas, the cells transformed with empty vector i.e. the non-recombinant plasmids, produce the blue colonies.
