Crossing over occurs at the four-strand stage when two homologous chromosomes, each consisting of a pair of sister chromatids, are paired. Each crossover involves just two of the four strands and generates two recombinant strands.
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The answer is long
The bone indicated by the arrow is femur bone. It should be classified as the long bone. Other example for long bones would be tibia and fibula. Short bone would be carpal or tarsal bones. Flat bone could be found in skull. Irregular bone would be the vertebrae or pelvic.
The miThe migration of birds.
