Below Are Short Fragments of DNA Sequences from Two Yeast

question 154

Multiple Choice

Below are short fragments of DNA sequences from two yeast strains (A and B) , which have been diverging from each other, as well as a short fragment from their common ancestor (C) . Yeast A: TGACTGCAAACATCCTAG
Yeast B: TGCCTGGACACATCGAAG
Yeast C: TGCCTGGAAACCTCCTAG
What type of information would best allow you to detect whether back substitutions occurred at any of the 18 nucleotides of the sequence as strain A evolved from the common ancestor?

• A) Additional sequences from strain A from regions near the 18 nucleotides
• B) Additional sequences from the ancestor from regions near the 18 nucleotides
• C) Phenotypic data from strain A and the ancestor
• D) The 18 nucleotides from yeast samples taken at various times between the ancestor and contemporary strain A
• E) Sequence data from closely related strains

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Definitions:

Vessel Elements

Components of the xylem in plants, responsible for conducting water and minerals from the roots to the rest of the plant.

Developing Root

The growth phase of a plant's root system which involves the formation, elongation, and differentiation of root cells and structures.

Developing Fruit

The growth phase of a fruit from fertilization of the ovary in plants to maturity, involving physiological and biochemical changes.

Sieve Tube Members

Plant cells that are part of the phloem, responsible for transporting sugars and other nutrients throughout the plant in a network of sieve tubes.