Many songbirds breed in north america in the spring and summer and then migrate to central and south america in the fall. they spend the winter in these warmer areas, where they feed and prepare for the spring migration north and another breeding season. two hypothetical species of sparrow, a and b, overwinter together in mixed flocks in costa rica. in spring, species a goes to the east coast of north america, and species b goes to the west coast. what can you say about the isolating mechanisms of these two species?

How can active reading strategies you? o a. they can you get into better physical shape. o b. they can you read fewer science articles. o c. they can you understand what you read. o d. they can you avoid reading altogether.

When in solution, a molecule that moves slowly across an artificial membrane moves rapidly across a plasma membrane. this molecule rapidly enters the cell regardless of whether its concentration is higher inside or outside the cell. using this information, which transport mechanism is most likely to be responsible for the movement of the molecule across a plasma membrane? view available hint(s)when in solution, a molecule that moves slowly across an artificial membrane moves rapidly across a plasma membrane. this molecule rapidly enters the cell regardless of whether its concentration is higher inside or outside the cell. using this information, which transport mechanism is most likely to be responsible for the movement of the molecule across a plasma membrane? active transportexocytosis

What is used to keep track of the gamates and possible offsprings combination