Simple tissue is made up of only one type of cell while complex tissue contains more than one type of cell working together. Primary permanent tissues in the body can be simple, complex, or secretory. Secretory tissue produces and secretes substances like hormones or enzymes.

1. Primary permanent tissue may be simple and complex. Simple tissue is made up of one type of cells
and complex tissue is made up of more than one type of cells working together as a unit. To these
may be added another kind of tissue the secretory tissue.
b