Why is the adaptive immune system considered a darwin machine?

Time ! for a smell to begin the process of registering in your brain, first you must a) inhale odor molecules into the nasal cavity b)transduce scent chemicals c)have a scent to inhale d)all answers can work

Despite the differences in mature plant cells, all of them are derived from meristem cells. the three major types of tissue systems develop from the meristem. meristems develop cells in all but which tissue?

Consider the classification levels of a human. eukarya ,animalia ,chordata ,mammalia ,primates, hominidae ,homo ,sapiens .which is the most specific taxonomic level in the classification system above? a sapiens b homo c hominidae d primates