Which of the following  levels of organization within  the biosphere is characterized by only biotic factors? a. biosphere b. ecosystem c. biome d. population

In natural selection, what is actually “selected? ” a) alleles are directly selected b) genotypes are directly selected c) phenotypes are directly selected d) entire populations are directly selected

Which of the following cell structures is significantly different between gram- positive and gram-negative bacteria?

Homo heidelbergensis was a tall, muscular hunter, who used both tools and weapons. because h. heidelbergensis was not a gatherer/forager, but ate a varied diet including meat and fish, we would expect to see what anatomical changes?