Biological difference between females and males.
A water lily will have more stomata. A desert cactus will have very few stomata, because in deserts plants face water shortage so in order to avoid loss of water cacti have adapted to the desert environment by possessing few stomata.
Louder, because the sound would have a stronger pitch for the ear it is closer to
<span>During prophase I, segments of chromatids are exchanged between homologous chromosomes.</span>Crossing over occurs<span> between prophase 1 and metaphase 1 and is the process where homologous chromosomes pair up with each other and exchange different segments of their genetic material to form recombinant chromosomes.
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The probable reason for the case would be that the sea floor 200 million years ago is now above the sea level.
The ocean floor is the eventual recycling center. While the Earth's continental crust can prevail for billions of years, the movement of tectonic plates results in subduction, that is when the crust of the ocean is pushed down into the present mantle. So, the ocean floor hardly endures longer than 200 million years.