Imagine that you've discovered a eukaryotic regulatory sequence thousands of base pairs away from the promoter, and that when this sequence is lost due to mutation, levels of gene expression decrease sharply. This sequence is . Select one: a. a promoter b. a promoter-proximal element c. a silencer d. an enhancer

The correct answer is option d, that is, an enhancer.

Explanation:

An enhancer refers to a short sequence of DNA, that is, about 50 to 1500 base pairs in length, which performs an essential role in enhancing the transcription process of a specific gene. These enhancers are also termed as transcription factors.  

An enhancer is found within the gene's coding region and can be present downstream of a gene, upstream of a gene, or thousands of base pairs away from a promoter sequence. As its primary role is to increase the process of transcription, thus, if anyhow, an enhancer is lost because of a mutation, the expression of a gene may even decline at a brisk rate.  

9.9 years

a = p(1 + rt) . . account balance after time t at rate r starting with principal p

3000 = 2500(1 + 0.0202t) . . filling in the given numbers

1.2 = 1 + 0.0202t . . divide by 2500

0.2 = 0.0202t . . . subtract 1

0.2/0.0202 = t ≈ 9.901

it will take about 9.9 years for the account balance to reach $3000.

jjrnfnf

explanation:

b r

he may like cookies