Question

question 13 (1 point) ✓ saved
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which of the pairs of plant structures below are homologous?
a) rose bush stem and flower
b) oak tree root and leaf
c) rose bush leaf and oak tree leaf
d) there are no homologous plant structures.
question 14 (1 point) ✓ saved
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many crustaceans (e.g., lobsters, shrimp, and crayfish) use their tails to swim, but crabs have reduced tails that curl under their shells and are not used in swimming. this is an example of ________.
a) a homologous structure
b) a vestigial trait
c) natural selection
d) convergent evolution

Explanation:

• Question 13: Homologous structures are those that have a common evolutionary origin. Rose bush leaf and oak tree leaf are both leaves, which are homologous as they share a common ancestral leaf structure. A rose bush stem and flower have different functions and evolutionary derivations. An oak tree root and leaf also have different functions and evolutionary paths.
• Question 14: A vestigial trait is a structure that has lost most or all of its original function through evolution. Crabs' reduced tails that are not used for swimming (while in related crustaceans like lobsters, shrimp, and crayfish, tails are used for swimming) is an example of a vestigial trait. A homologous structure would imply similar function and common origin with more functional similarity. Natural selection is the process by which organisms better adapted to their environment tend to survive and reproduce. Convergent evolution is when different organisms independently evolve similar traits.

Answer:

Question 13: C. Rose bush leaf and oak tree leaf
Question 14: B. a vestigial trait