Ex7: The Skin & Other Body Membranes

I. Introduction/Background Information

        Refer to the Lab worksheet : https://sites.google.com/site/physiolablist/

There are several sections to this lab, generally designed to assist students in understanding the structures & functions of skin & other body membranes. The objectives of this lab are:

1. to recount important functions of the skin/integumentary system
2. to recognize and name the following structures from a slide, model or diagram
• epidermis (including strata), 
• dermis (papillary & reticular layers
• hair follicles & hair
• sebaceous glands & sweat glands
3. to compare the properties of the dermis & epidermis
4. to describe the distribution and function of the sebaceous glands, sweat glands, and hair 
5. to differentiate between eccrine & apocrine sweat glands
6. to ennumerate the factors determining skin color
7. to describe the function of melanin
8. to compare the structure and function of the major membrane types
9. to list the general functions of each membrane type and note its location in the body
10. to recognize by microscopic examination epidermal, mucous, and serous membranes

II. Hypothesis

Part 1: Basic structure of the skin: If students read about structures as they locate them on a skin model then they will be able to write out a response to each objective
Part 2: Appendages of the Skin: If students examine a prepared slide of human skin then they will be able to identify skin structures on a drawing.
Part 3: Plotting the Distribution of sweat glands: If bond paper is taped to skin coated with iodine and left for 20 minutes, then a distribution of sweat glands will be mapped out because the sweat glands will dissolve the iodine, which will then be absorbed by the paper.  As it reacts with the starch in the bond paper each sweat gland will produce a blue/black dot.
Part 4: Classification of Membranes: If students examine slides from trachea and small intestine, heart, as well as a freshly cut joint, then they can compare mucous, serous and synovial membranes.

III. Materials

    Model of Skin, prepared slides/pictures, iodine, 1cm x 1 cm bond paper squares, tape.

IV. Procedure

“See Lab Instructions” (you may include pictures of procedure)

Part 1: Basic structure of the skin: Compare the following structures identified in the pictures with the model in the classroom.

Skin slide

Human Skin Slide

Part 2: Appendages of the Skin:
Part 3: Plotting the Distribution of sweat glands: Insert a photo of each of your sweat distribution patches.  Label them "palm" and "forearm".
Part 4: Classification of Membranes:

pseudostratified ciliated columnar epithelium

mucosa of trachea

mucosa of small intestine

drawing of one villus

pericardium (around the heart)

V. Results/Observation/Data
List answers to questions from each section of the lab

Part 1: Basic structure of the skin: (No questions in this section)
Part 2: Appendages of the Skin:
What additional features did you observe in the two photos of skin (above) that you didn't see in the slides of stratified squamous epithelium that you studied for Chapter 3?
Part 3: Plotting the Distribution of sweat glands:
Which skin area tested had a greater density of sweat glands?
Labeled  Pictures:

Part 4: Classification of Membranes:
How do the roles of trachea mucosa and small intestine mucosa differ? How are they the same?


Do you think that mucous membranes have a high regenerative capacity?  Explain why or why not.




The pericardium is an example of a serous membrane.  It's too tiny to see, but the endothelium is composed of simple squamous epithelium.  List the specific names of the following serous membranes:
covering of the heart:
Lining of the cavity in which the heart resides:
Covering of the lungs:
Lining of the thoracic cavity:
Covering on the viscera:
Lining of the visceral cavity:
 

VI. Conclusion: Respond to each objective. What did you learn?

1.  What are the important functions of the skin/integumentary system?
2. Can you recognize and name the following structures from a slide, model or diagram?
• epidermis (including strata), 
• dermis (papillary & reticular layers
• hair follicles & hair
• sebaceous glands & sweat glands
3. Compare the properties of the dermis & epidermis
4. Describe the distribution and function of the sebaceous glands, sweat glands, and hair 
5. Differentiate between eccrine & apocrine sweat glands
6. Ennumerate the factors determining skin color
7. Describe the function of melanin
8. Compare the structure and function of the major membrane types
9. List the general functions of each membrane type and note its location in the body
10. Can you recognize by microscopic examination epidermal, mucous, and serous membranes?