Question

dna sequence and ancestry

• dna is inherited from your parents therefore related organisms share dna sequences
• fewer differences the more closely related the species
• the more differences the less related the species

example:
black bear: ggaccccagatcagtaggact
grizzly bear: ggacgcagatcatttaggact
polar bear: ggaccaagattattaggagt
value: 10
is the black bear more closely related to the grizzly bear oor the polar bear?
○ a. grizzly bear
○ b. polar bear
○ c. related to both equally

Explanation:

Compare the DNA sequences of the Black Bear with the Grizzly Bear and the Polar Bear. Count the differences. Fewer differences mean a closer relation.
For Black Bear (GGACCCCAGATCAGTAGGACT) and Grizzly Bear (GGACGCAGATCATTAGGACT):

• The differences are at positions 6 (C vs G) and 12 (G vs T). So 2 differences.

For Black Bear (GGACCCCAGATCAGTAGGACT) and Polar Bear (GGACCAAGATTATTAGAGT):

• The differences are at positions 6 (C vs A), 10 (C vs T), 12 (G vs T), 13 (A vs A - no), 14 (G vs G - no), 15 (G vs A), 16 (A vs G). More than 2 differences.

Answer:

A. Grizzly Bear