Mammal like reptiles and exotic ocean animals were present during the permian period. what types of life were not on earth 250 million years ago?

Dinosaurs, flowers, animals with fur and flowering plants

Explanation:

Mass extinction occurs when more than half of the world’s species die in a geologically short period. A species is a group of organisms similar in appearance, anatomy, physiology, and genetics.

The environment changes so fast that most species can’t adapt or evolve, so they go extinct.

after a the power stroke, adp is released, but the cross-bridge formed is still in place. atp then binds to myosin, moving the myosin to its high-energy state, releasing the myosin head from the actin active site.

the answer is true when observing or determining population size, a direct observation is use, in which each organism is counted in a population or in an area. one benefit of this measure is that you get the exact population count but it will take a long time to  determine  the  size  of a  population.