• Be able to identify the major types of connective tissue and understand how the structure of each reflects its function.
• Understand how to distinguish the various cells found in connective tissue (fibroblasts, adipocytes, mast cells, plasma cells, macrophages, and undifferentiated mesenchymal cells) and to describe their functions and key features
• Know the composition, morphology, and variations in distribution of the ground substance and the three types of extracellular fibers and their functions.

We will start with primitive (embryonic) connective tissue: mesenchyme (Fig 5-1).

• Examine the cross section of a mammalian embryo (slide 91) and locate regions of mesenchyme within and around the developing organs.

What are some major differences between mesenchymal cells and epithelial cells?

What is the fibrous material between the mesenchymal cells and what does the "empty" space around the fibers represent?

Let's now take a look at the common forms of mature connective tissue.