The control of calcitonin excretion is an example of direct ________ regulation.

The enzyme renin is responsible for the activation of

_____ – lymphocytes are densely packed in area of loose connective tissue; 1 millimeter in diameter, found beneath the epithelial lining of the respiratory, digestive and urinary tracts

Figure 20-2 Cardiac CycleUse Figure 20-2 to answer the following questions:What occurs at “A” on the graph?

The ability of certain cells to respond to changes in their chemical environment is called _____

_____ – lymphocytes are densely packed in area of loose connective tissue; 1 millimeter in diameter, found beneath the epithelial lining of the respiratory, digestive and urinary tracts

Cushing’s disease results from an excess of

Specific defenses depend on the activities of

The child was, however, tall for his age.

Specific defenses depend on the activities of