Which of the following is an example of a tissue? A. Lung
B. Digestive tract
C. Bone
D. Heart

With the word calcite wich completes the analogy mineral, erosion, marble, or aragonite

The vaccine in a flu shot contains weakened flu viruses. how does a flu shot work with the immune system? a. it destroys lymphocytes. b. it destroys macrophages. c. it activates macrophages. d. it activates lymphocytes.

Which is an important function of normal flora? a. aid with bone marrow production. b. crowd out pathogenic bacteria. c. destroy digestive track pathogens. d. manufacture iron in the bloodstream.