What is the temporary organ of pregnancy, which functions to supply the developing fetus with oxygen and nutrients?

Which of the following terms describes excessive fluoride causing staining of the enamel?

a. fluoridation b. fluorosis c. caries d. attrition

When comparing x-rays and gamma rays, a key distinction is in the

a. origin of the emission. b. mass of the emission. c. velocity of the emission. d. all of the above