Question

A. When we think of structure, we tend to consider only those features a tissue does have and how the presence of the feature allows for function. But we can also think in reverse and consider features a tissue does not have. The lack of a feature can also allow the tissue to function in a certain way. Consider avascular tissues. Using either epithelial tissue or cartilage, can you think why lacking blood vessels is necessary for its function? B. Rank the following in terms of level of protection. #1 being the most protective. Explain your ranking: Stratified cuboidal Stratified squamous Pseudostratified columnar Stratified columnar C.Any epithelial tissue coating the vessel wall could theoretically reduce friction. So why is simple squamous the only one that is actually located coating a vessel wall? Meaning, why is there not simple cuboidal or stratified squamous coating a vessel wall to reduce friction? D. The ducts of some glands contain simple cuboidal while the ducts of other glands are stratified cuboidal. Both of these tissues allow for secretion so why do some have simple but others have stratified cuboidal? E. How does the structural difference between hyaline cartilage, elastic cartilage, and fibrocartilage allow for functional differences between the three types of cartilage? F. Why do you think only cartilage and bone have cells in lacunae? G. Dense CT is vascular but poorly vascular so they heal very slowly, sometimes not at all. This is why injuries to tendons/ligaments often require surgery to repair them. Since cartilage is avascular, most, if not all, cartilage injuries require surgery to repair them. However, epithelial tissue is avascular…but has a tremendous ability to heal. Epithelial tissue is one of fastest healing tissues. Since both epithelial tissue and cartilage are avascular, why does one heal very fast but the other not at all. Healing is a functional feature and, as we know, this function must be due to structure. Examine the structure of both tissues. H. How does the structural differences between dense regular and dense irregular allow for the functional differences between them?

Answer 1

Answers to A and B.