This diagram shows how oxygen is cycled through an ecosystem. which part of this diagram does not contain an element from the periodic table that is essential to life?

a. sugars being formed in the tree's leaves
b. sunlight rays hitting the earth's surface
c. the rhino breathing in oxygen
d. the tree taking in carbon dioxide

Were does condensation occur? a) hydroshereb) lithosherec) boishered) atmosphere

In an experiment examining the effects tai chi on arthritis pain, callahan (2010) selected a large sample of individuals with doctor-diagnosed arthritis. half of the participants immediately began a tai chi course and the other half (the control group) waited 8 weeks before beginning. at the end of 8 weeks, the individuals who had experienced tai chi had less arthritis pain that those who had not participated in the course.

24. how are vaccines used to keep people healthy?