Unlike bird wings, insect wings do not have bones or feathers. why are there differences in the structures of bird and insect wings?

There are differences in the structures of bird and insect wings because birds are vertebrates and, therefore, have internal structural members. Insects are invertebrate and have external structural members.

Recombinant DNA (or rDNA) is made by combining DNA from two or more sources. ... DNA fragments are cut out of their normal position in the chromosome using restriction enzymes (also called restriction endonucleases) and then inserted into other chromosomes or DNA molecules using enzymes called ligases.

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