Answer:
A. Genetic changes among and within populations
Explanation:
Macro evolution is the theory that animals evolved over time into new species while micro evolution is more minute changes within a species, like a genetic mutation to help the species adapt to their environment. An example would be of a genetic mutation in the fur color of bears to make different types of bears like black bears, brown bears, polar bears, etc
B. The cells in between failed to grow
Making them not the same but not very different
B. Jet streams are very powerful air currents, and it's very inconvenient for a plane to have to go against the direction of a current. They have to plan their flights to avoid these currents or be aided by them.
Initiation, elongation, and termination.
Blood circulation is the answer
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