As many as 30 to 50 percent of the population may experience a negative physiological reaction to alcohol, causing them to develop flushed skin, nausea or an abnormal heartbeat-sometimes after only a single drink.

The concept of keystone species is controversial among ecologists because most organisms are highly interdependent. if each of the trophic levels is dependant on all others how can we say one is most important

Which sentence best describes the relationship between chlorophyll and the chloroplast? a.) chlorophyll is a chemical found in a chloroplast. b.) chloroplast is a chemical found in a chlorophyll. c.) both chlorophyll and chloroplasts are found in animals. d.) both chlorophyll and chloroplasts make carbon dioxide.

Anne, an intern in a microbiology lab, was observing the characteristics of various specimens of protists. match each specimen to the category of protist to which it belongs.