1. What do epidemiologists study? A. risk factors for different diseases

B. how often a disease occurs in a particular area or group of people

C. blood and heart diseases

D. Non-infectious diseases and their causes

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

Mrna decodes information from the original dna master plan to build proteins in the during the process of ribosomes.

Matthew decided he wanted to hike up mount everest. on his way to the top, it began to snow and the temperature dropped to -10°f. matthew forgot to wear a heavy jacket so his body began to shiver beyond control. in this case, matthew's body shivering is the to a drop in temperature. * 0 points reflex stimuli responce environmental facto