"Integumentary System Lab modified"
Integumentary System Materials Hand magnifier Compound microscope Prepared microscope slide of heavily pigmented skin Prepared microscope slide of human scalp or axilla Forceps Microscope slide and coverslip Procedure 1. Use the hand magnifier to do the following: a. Observe the skin, hair, and nails of your hand. b. Compare the type and distribution of hairs on the front and back of your forearm. 2. Pull out a single hair with the forceps and mount it on a microscope slide under a coverslip. Use the hand magnifier to observe the root and shaft of the hair. Note the scalelike parts that make up the shaft. 3. Complete Part A of the laboratory report. 4. Use low-power magnification of the compound microscope and proceed as follows: a. Observe the prepared slide of human scalp or axilla. b. Locate the epidermis, dermis, and subcutaneous layer, a hair follicle, an arrector pili muscle, a sebaceous gland, and a sweat gland. c. Using low-power magnification, locate a hair follicle that has been sectioned longitudinally through its bulblike base, a sebaceous gland close to the follicle, and a sweat gland. Observe the detailed structure of these parts with high power magnification. d. Observe the dense connective tissue that makes up the bulk of the dermis. e. Observe the adipose tissue that composes most of the subcutaneous layer. 5. Observe the prepared slide of heavily pigmented skin with low power magnification. Note that the pigment is most abundant in the epidermis. Focus on this region with the high-power objective. a. Focus on the epidermis with high power and locate the stratum corneum and stratum basale. Note how the shapes of the cells in these two layers differ. b. Observe the dense connective tissue that makes up the bulk of the dermis. c. Observe the adipose tissue that composes most of the subcutaneous layer. 6. Use your labeled digram to help answer the laboratory report questions. 7. Complete Parts B, C, and D of the laboratory report. Part A 1. How does the skin on your palm differ from that on the posterior (back) of your hand? 2. Describe the differences you observed in the type and distribution of hair on the anterior (front) and posterior of your forearm. 3. Explain how the hair is formed. Part B 1. Distinguish among the epidermis, dermis, and subcutaneous layers. 2. How do the cells of the stratum corneum and stratum basale differ? Part C 1. In which layer of skin are follicles usually found? 2. Which glands are usually associated with hair follicles? 3. In which layer of skin are sweat glands usually located? Part D Sketch and label a vertical section of human skin, using the scanning (low-power) objective.