Final answer:
Focal adhesions and hemidesmosomes serve the purpose of cell adhesion to the extracellular matrix. Focal adhesions act as mechanical linkers and signaling centers, while hemidesmosomes connect epithelial cells to the basement membrane.
Step-by-step explanation:
Focal adhesions and hemidesmosomes serve the purpose of cell adhesion to the extracellular matrix. Focal adhesions act as mechanical linkers that anchor the cell to its substrate, while also functioning as signaling centers that activate biochemical signaling molecules. Hemidesmosomes, on the other hand, are specialized adhesion structures that connect epithelial cells to the underlying basement membrane.