When sufficient heat is applied, double-stranded DNA denatures into two single-stranded molecules as the heat breaks all of the hydrogen bonds. In an experiment, molecules of single-stranded DNA from species X are separately hybridized with putatively homologous single-stranded DNA molecules from five species (A-E). The hybridized DNAs are then heated, and the temperature at which complete denaturation occurs is recorded. Based on the data below, which species is probably most closely related to species X?

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#Question id: 15764

#Unit 5. Developmental Biology

An alternative (but not mutually exclusive) mode of retaining cell homeostasis is the:

A. Asymmetric mode of stem cell division

B. Symmetric mode of stem cell division.

C. Single stem cell asymmetry mode of stem cell division

D. Population asymmetry mode of stem cell division.

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#Question id: 4658

#Unit 11. Evolution and Behavior

Members of two different species possess a similar-looking structure that they use in a similar fashion to perform the same function. Which information would best help distinguish between an explanation based on homology versus one based on convergent evolution?

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#Question id: 10451

#Unit 6. System Physiology – Plant

Which induction is responsible for “uncages” the kinase domain of phototropin and leads to autophosphorylation

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#Question id: 802

#Unit 1. Molecules and their Interaction Relevant to Biology

A single-stranded DNA molecule contains 40 nucleotides with equal amounts of A, C, G, and T. This DNA strand can combine with a complementary DNA strand to form a double-stranded DNA molecule. Which is a possible sequence and structure for this DNA molecule?

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#Question id: 118

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following best describes the cholesterol molecule?