. a. Mice engineered to block expression of the geneencoding the telomerase protein age at a muchfaster rate than normal and have decreased lifespans. When expression of the telomerase proteinis turned back on in mice that are prematurely old,many negative effects of this aging are rapidly anddramatically reversed. Provide a possible explanation for these results.b. The results of these mouse experiments have ledsome researchers to propose that treatments thatcould lead to overexpression of the telomerase genemight serve as a “fountain of youth” leading to reversal of aging in humans. Why do you think weshould be very cautious about trying such treatments? Your argument should address why it mightbe advantageous to multicellular organisms for mostof their somatic cells not to express telomerase.

. a. Mice engineered to block expression of the geneencoding the telomerase protein age at a muchfaster rate than normal and have decreased lifespans. When expression of the telomerase proteinis turned back on in mice that are prematurely old,many negative effects of this aging are rapidly anddramatically reversed. Provide a possible explanation for these results.b. The results of these mouse experiments have ledsome researchers to propose that treatments thatcould lead to overexpression of the telomerase genemight serve as a “fountain of youth” leading to reversal of aging in humans. Why do you think weshould be very cautious about trying such treatments? Your argument should address why it mightbe advantageous to multicellular organisms for mostof their somatic cells not to express telomerase.

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Description: . a. Mice engineered to block expression of the geneencoding the telomerase protein age at a muchfaster rate than normal and have decreased lifespans. When expression of the telomerase proteinis turned back on in mice that are prematurely old,many ne

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter8: The Structure, Replication, And Chromosomal Organization Of Dna

Section8.4: The Watson-crick Model Of Dna Structure

Problem 1GR: Two genes associated with breast cancer, BRCA1 and BRCA2, were discovered in 1994 and 1995,...

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2. a. You want to create a genetic construct that will express GFP in Drosophila. In addition to the GFPcoding sequence, what DNA element(s) must youinclude in order to express this protein in flies if theconstruct were integrated into the Drosophila genome? Where should such DNA element(s) be located? How would you ensure that GFP is expressedonly in certain tissues of the fly, such as the wing?b. Suppose you insert the GFP coding region plus allof the DNA elements required by the answer to part(a)—except the enhancer—between inverted repeatsfound at the ends of a particular transposable element.Because all of the DNA sequences located betweenthese inverted repeats can move from place to placein the Drosophila genome, you can generate manydifferent fly strains, each with the construct integrated at a different genomic location. You now examine animals from each strain for GFPfluorescence. Animals from different strains showdifferent patterns: some glow green in the eyes,others in…