Question about identifying epithelial cells in tissue specimens

Q. Some of the cells in the stratified squamous epithelium on slide 53 look thicker and almost cuboidal while cells of stratified cuboidal epithelium on slide 54 are almost squished like squamous (especially around the folds in the lining), making them hard for me to distinguish them if I were to be asked without context of where they’re from. What is the typical process in distinguishing the epithelium type of real tissue specimens?

A. I totally get that! It can be really hard when you’re looking at these specimens for the first time; I remember feeling like I could tell what was what if it was pointed out to me – but if I had a slide without arrows, I felt lost. Continue reading

Questions on zonula adherens and hemidesmosomes

Q. On slide 23 (zonula adherens) it is mentioned that actin filaments insert into attachment plaques. And then I believe on slide 19 you say in the lecture that the purple-ish ridges within the zonula adherens are the attachment plaques. Would that make the microfilament labelled on 19 the actin filaments mentioned in 23? In other words, are the terms interchangeable or are they different filaments?

A. The short answer is yes: actin filaments are the same thing as microfilaments (the terms are interchangeable).

But I can’t resist writing a longer answer! I just want to point out a couple things on those two slides and then show you another diagram to make sure that the structure of the zonula adherens is clear to you. Continue reading

Questions about glands

Here are some great questions about glandular cells!

Q. I wanted to clear up some confusion I have about exocrine glands and glandular cells types. I understand that there are 3 different glands; merocrine, holocrine, and apocrine. Within these glands with specific processes of secretion, there are different kinds of glandular epithelial cells; ion-transporting, serous secretory, mucous secretory, neuroendocrine, and myoepithelial cells. Is this correct? Continue reading