introductory histology tutorial i epithelial tissues

Introductory Histology Tutorial IIntroductory Histology Tutorial IEpithelial TissuesEpithelial Tissues

Human Anatomy & Physiology IHuman Anatomy & Physiology I

Assembled by Stephen Shoemake

{Click mouse to advance}

NAVIGATION NAVIGATION

= returns you to the previous slide.

= returns you to the Index, regardless of which slide you are on currently.

Click on any empty space to advance to the next slide.

This exercise is set up so that the first thing you see is an image of a tissue without any explanatory text. Try to guess what type of tissue you are looking by identifying unique structures or characteristics you can see in the picture. After you have guessed, click again to get the answer and an explanation of characteristics you should be looking for.

If you know which image you want to see, clicking on the name of the image in the index will take you directly to an image of that tissue.

INSTRUCTIONSINSTRUCTIONS

Index: Epithelial tissuesIndex: Epithelial tissues

Go directly to tissues

Epithelial types

Simple squamous epitheliumSimple Cuboidal epitheliumSimple Columnar epithelium

Quick Quiz

Stratified squamous epitheliumStratified cuboidal epithelium

Pseudostratified columnar epithelium

The red arrows above point at a single layer of flattened cells that line a blood vessel. (The reddish stuff at the bottom of the screen is blood.) Note the flattened nuclei (dark ovals) which clue you in on the shape of the cells themselves.

What type of epithelium is shown?

This is a simple squamous epitheliumsimple squamous epithelium. There is another one at the orange arrow.

AnswerAnswer

What type of tissue is indicated by the blue arrow?

This is also a simple squamous epitheliumsimple squamous epithelium. This one is the epithelium that lines the renal

corpuscles in the kidney.

AnswerAnswer

FYI:FYI: This is a surface view of a simple squamous epithelium.

Here is an epithelium lining a duct. What type of epithelium is it?

This is a simple cuboidalsimple cuboidal epitheliumepithelium. The cells are about as tall as they are wide.

AnswerAnswer

What type of tissue is indicated by the red arrows?

This is a simple columnar epitheliumsimple columnar epithelium. These light purple cells are clearly taller than they are wide. The dark purple ovals

are their nuclei.

AnswerAnswer

The tissue indicated at “a” would be classified as…?

a

AnswerAnswer

This is a stratified squamous epitheliumstratified squamous epithelium. This slide is a section of the tissue that lines

your inner cheek.

This is a slide of human skin. How would you classify the layer indicated by “a”?

a

This is also stratified squamous epitheliumstratified squamous epithelium. If you look closely you will see multiple layers of

flattened cells.

a

AnswerAnswer

The main difference between skin and the cells that line your cheek is that in skin, the outer layer

of cells has become filled with a proteinacous substance called keratin. (become keratinized)

More info.More info.

The light purple layer of the epidermis looks very much like those cheek cells.

More info.More info.

The epithelial layer which lines the cavity (white space) seen here would be classified as…?

……stratified cuboidal epitheliumstratified cuboidal epithelium. Note that most of this cavity is lined by two layers of cells which

are “block-like” in shape.

The epithelium at the surface (top) here would be classified as…

……pseudostratified columnar epitheliumpseudostratified columnar epithelium. Although the cells appear to be in several layers, they are actually all in contact with the basement

membrane.

Quick QuizQuick Quiz

For each of the following slides, try to guess which type of epithelium you are looking at. Before you check the answer, be able to justify to yourself why you think it is that type.

The outlined structure is a “tube” lined by Simple Cuboidal epitheliumSimple Cuboidal epithelium . There are also

other similar tubes surrounding this one.

This is Simple Columnar epitheliumSimple Columnar epithelium

The layer indicated is...

Stratified squamous epithelium.Stratified squamous epithelium.

The epithelium which lines this “tube” would be classified as...

……stratified cuboidal epithelium.stratified cuboidal epithelium. Notice that there are two layers of cells that are about as wide

as they are tall.

The EndThe End

Most of the images on this tutorial were taken from one of two excellent Histology sites on the Internet. Check them out if you want to see many more images of tissues.

JayDoc HistoWeb: JayDoc HistoWeb: http://www.kumc.edu/instruction/medicine/anatomy/histoweb/

Loyola University Medical Education Network: Histology Loyola University Medical Education Network: Histology http://www.lumen.luc.edu/lumen/MedEd/Histo/frames/histo_frames.html

I have links to both of these sites on my Web page under “Miscellaneous links”.