before a cell divides, it copies all of its chromosomes. while the two copies of a chromosome are attached they are called

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?

Dna and rna share a number of similarities,but they also differ in certain aspects of their structure. wich nitrogenous base is found in rna but is not found in dna

The image shows the evolution of a species of fish. a few fish from a population developed different social behaviors and evolved into different species. two fish according to the image, the fish underwent . the new species of fish had mating seasons that were different from that of the original fish. because of the differences in mating seasons, the fish underwent reproductive isolation. this mode of isolation would be .