HOSA Dental Terminology Practice

What are hemidesmosomes?

1. Full desmosomes between two cells

2. Half desmosomes connecting epithelial cells to the basal lamina

3. Proteins found only in the connective tissue

4. Structures that help in muscle contraction

The correct answer is: Half desmosomes connecting epithelial cells to the basal lamina

Hemidesmosomes are specialized structures that serve as anchors, connecting epithelial cells to the underlying basal lamina, which is a layer of connective tissue. This anchoring is crucial for tissue integrity and stability, allowing epithelial cells to adhere firmly to the tissue beneath them. The term "hemidesmosomes" reflects their unique composition; they are considered to be "half" of a desmosome, which typically connects two cells together. Unlike full desmosomes that link adjacent epithelial cells, hemidesmosomes connect the epithelial cell to the extracellular matrix of the basal lamina. This connection is vital for maintaining the structural integrity of epithelial tissues, especially in areas that experience significant mechanical stress. The other options do not accurately describe hemidesmosomes. While full desmosomes involve connections between two cells, hemidesmosomes uniquely focus on the attachment to the basal lamina. Additionally, hemidesmosomes are not exclusive to connective tissue, as they are part of the epithelial cell structure, and they do not play a role in muscle contraction. Instead, their primary function is to ensure the adhesion of epithelial cells to their extracellular environment, which is fundamental in various physiological processes.