Exercise 1: Structures of the Skin
Fill in the names of the numbered structures in the diagram in the table below the picture.
1 Hair Shaft|7 Hypodermis|
2 Arrector pilli muscle|8 Dermis|
3 Sebaceous(oil) gland|9 Epidermis|
4 Hair follicle|10 Subpapillary vascular plexus|
5 Eccrine sweat gland|11 Dermal papillae|
6 Hair follicle receptor(root hair plexus)|12 Pore|
QUESTIONS:
A. How does the skin tan when exposed to ultraviolet light? When exposed to the sun’s UV rays, your skin’s melanocytes produce melanin, the dark pigment that creates a tan. A tan is your skin’s attempt to prevent UV rays from doing any further damage to the sensitive skin cells in your epidermis. …show more content…
B. Describe the functions of the epidermis. The epidermis is the outermost layer of the skin; it acts as the body's major barrier against the environment.
C. Describe the functions of the sweat glands. The sweat glands secrete transparent liquid (sweat) containing water and salts from the body in order to regulate body temperature. Some types of sweat glands also produce pheromones. Pheromones are chemicals that are released by the body to communicate with or attract others.
D. Compare the structure of the epidermis to that of the dermis. epidermis is the upper layer of the skin whereas dermis is the lower layer of the skin. The main function of epidermis is to protect the skin from fungal infection whereas dermis contains nerve endings which help in sensations.
E. Fill in the following table by either inserting the name of the structure/cell or by giving its function(s):
Structure/Cell|Function(s)| melanocytes|Makes a pigment for tanning|
Langerhans cells|Ingest foreign substances and are key activators of our immune system.|
Tactile Cells|Found on nerve endings|
Stratum lucidum|The Stratum lucidum is the second layer of the epidermis and varies in thickness throughout the body depending mainly on frictional forces and is thickest on the palms of the hands and soles of the feet. The stratum lucidum is normally only well seen in thick epidermis|
Eccrine sweat gland|The blood supply here provides radiational cooling for the body|
Exercise 2: Microscopic Structure of the Skin
Sketch and label your keratinized stratified squamous epithelium slide in the space below.
Be sure to label all of the structures in the epidermis and dermis you were able to find:
QUESTIONS:
A. Compare your slide to the photomicrograph example in the lab procedure. How are they the same and how are they different? Propose a reason why you would see several differences between different slides of skin. They are similar in you can obviously pick out the dermis and you can obviously see the 4 different stratum in both pics. They are different in the photomicrograph example it’s hard to find the melanocyte and the nerve endings.
B. What is keratin? Keratin is an extremely strong protein which is a major component in skin, hair, nails, and hooves.
C. Why is skin keratinized? To protect the epidermis.
Exercise 3: Clinical Conditions of the Skin
QUESTIONS:
A. What are the three types of skin cancer? Basal cell carcinoma, Squamous cell carcinoma, Melanoma
B. Which type of skin cancer is easily treatable? Basal cell carcinoma
C. Explain why melanoma is so dangerous. Because it’s highly metastatic and resistant to
chemotherapy
D. What factors can cause acne? Stress, hormones, bacterial infections
E. What is a common myth about the cause of acne? Chocolate, pizza, and French fries cause acne[->0]
F. What are some treatments for acne? Oral contraceptives in females, Topical bactericidal, Topical antibiotics, Oral antibiotics, Topical retinoids,
G. Describe the signs of first, second and third degree burns. First Degree Burns: localized redness, swelling, and pain.
Second degree burns: Symptoms mimic those of 1st degree burns and blisters also occur.
Third degree burns: area may appear grey-white, cherry red or blackened and initially there is little or no edema. Also since the nerve endings have been damage there is no pain.
H. What are the principle effects of aging on the skin? As old age approaches the rate of epidermal cell replacement slows down. All lubricating substances become deficient. Skin then becomes dry and itchy. Number Hair follicles decrease. Wrinkles begin to show due to decreasing elasticity of the skin.
[->0] - http://acne.about.com/od/acnetriggers/tp/Food-And-Acne.htm