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Which of the following statement concerning gene duplication is most correct?

A.) Gene duplications are necessary to meet the cell's requirements for some RNA trnscripts

B.) Pseudogenes are translated into proteins but lack function

C.) B-Tublins and B-like globins are examples of genes that rose independently yet carry out similar functions

D.) Gene duplication involves unequal crossover between homologous repetitive DNA sequences during mitosis


answer -c?


no, please try again.




the correct answer is A. Here is the explanation, i copied it from a question book for step 1. This is their explanation:

Asa many as 100 to 1000 gene families contain similar sequences. B-Tublins and B-like globins are perfect examples of duplicated gene families. At least 2 nonfunctional regions in the human B-like globin gene cluster have sequences similar to functional B-like genes. Analysis of their DNA sequences shows that they retain their intron-exon structure, but some sequence drift has resulted in sequences that block transcription or terminate protein translation. Some gene duplications, such as those for ribosomal RNA (rRNA) and tRNA, along with genes coding fort histones, are necessary to meet the demands of the cell for messenger RNA (mRNA) transcripts. Althought there is no accepted model for duplication, it is thought to involve unequal crossover during meiosis.


Wow! Thank You :?

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