THE INTEGUMENTARY SYSTEM

INTRODUCTION

____________________ - another name for skin

____________________ - sheetlike organs

1 square inch of skin contains 500 sweat glands, 1,000 nerve endings, 100 oil glands, 150 sensors for pressure, 75 heat sensors, 10 cold sensors, and millions of cells.

I. The Skin

   A. Structure - 2 layers   Click for diagram.  Click for answers to diagram.

      1. ____________________

         a. outermost and thinnest

         b. composed of layers of ____________________ epithelium

         c. innermost layer of cells  reproduces and moves upward

         d. As cells approach surface they are filled with ____________________, a waterproof protein.

         e. ____________________ - outermost layer

         f. Pigment layer - contains ____________________ which contain melanin

         g. ____________________- layer of cells that continually undergoes  mitosis

         h. ____________________ - caused by breakdown between cells or layers of skin.

         i. Dermal-epidermal junction - where the two layers meet

      2. ____________________

         a. Deeper and thicker layer

         b. Upper layer contains parallel dermal papillae

         c. Ridges & grooves form ____________________

         d. Deep areas filled with collagen  and elastic fibers

         e. Number of ____________________ fibers  decreases with age causing  wrinkles

         f. Contains nerve endings, muscle  fibers, hair follicles, sweat glands, sebaceous glands, and 

            blood vessels.

      3. ____________________ - a thick layer of  connective tissue and fat that  insulates the body,    
 

          protects and pads underlying tissue.

   B. Appendages of the Skin

      1. ____________________

         a. ____________________ - soft hair of fetus and  newborn.

         b. Hair growth requires hair  follicles

         c. Hair ____________________ begins growth

         d. Hair ____________________ - hidden in follicle

         e. Hair ____________________ - visible part of hair

         f. Arrector pili - smooth muscles that produce "____________________"

      2. Receptors

         a. Specialized nerve endings make skin a sense organ

         b. ____________________ corpuscles - light  touch

         c. ____________________ corpuscles - deep  pressure

      3. Nails

         a. Produced by epidermal cells

         b. ____________________ - visible part

         c. ____________________ - lies hidden by cuticle

         d. ____________________ - crescent-shaped area near the root

         e. Nail beds may change color  because of ____________________. (cyanosis)

      4. Skin Glands

         a. ____________________ Sweat Glands

            (1) Most numerous

            (2) Produces perspiration on body  surface

         b. ____________________ Sweat Glands

            (1) Primarily in axilla and around genitalia

            (2) Secretion thicker, milkier, than eccrine perspiration

            (3) Breakdown of this secretion by bacteria produces ____________________

         c. Sweat glands also called  ____________________ glands

         d. ____________________ Glands

            (1) Secrete ____________________ (sebum)

            (2) Secretion increases during ____________________ because of sex  hormones.

            (3) Sebum darkens in pores  causing ____________________.

            (4) ____________________ - inflamation of a sebaceous gland and  surrounding area

            (5) ____________________ - secondary infection beneath the epidermis

   C. Functions of Skin

      1. Protection from

         a. ____________________

         b. ____________________

         c. ____________________

         d. ____________________

      2. Temperature regulation

         a. Skin releases almost ____________________  calories of heat / day.

         b. Mechanisms of heat regulation

            (1) ____________________

            (2) Regulation of flow of blood

      3. Sense organ activity

   D. Burns

      1. Treatment depends on total area and   severity of burn

         a. Rule of nines   Click for picture  

         b. 11 areas of 9% 

            (head, left arm, right arm, anterior thoracic, 
             anterior abdominal, anterior left leg, anterior 
             right leg, posterior left leg, posterior right 
             leg, upper back, lower back)
         c. 1% around genitals

 
     2. Classification of burns

         a. ____________________ Degree - only surface tissue (like a sunburn)

         b. Second degree - involves the deep ____________________ tissue and upper dermis

         c. Third degree - complete  destruction of epidermis and  ____________________

            (1) May involve muscle and bone

            (2) No ____________________ at first because  nerve endings are destroyed




II. Types of body Membranes

    A. Classification of membranes

       1. Epithelial membranes - composed of  epithelium and connective tissue

       2. Connective tissue membranes -   composed entirely of connective  tissue

    B. Epithelial Membranes

       1. ____________________ - the skin

       2. ____________________ - simple squamous on connective tissue foundation

          a. Types

             (1) ____________________- line body cavities

             (2) ____________________ - cover organs

          b. Examples

             (1) ____________________ pleura - line walls of the chest cavity

             (2) Visceral pleura - cover  ____________________

             (3) Parietal ____________________ - lines  walls of abdominal cavity

             (4) Visceral peritoneum - covers ____________________

          c. Diseases

             (1) ____________________ - inflammation of  the membranes that line the chest cavity and
cover lungs

             (2) ____________________ - inflammation of the serous membranes in  the abdominal
cavity

       3. ____________________ membranes

          a. Line body surfaces that open to the exterior

          b. Produce mucus

    C. Connective Tissue Membranes

       1. Do not contain epithelial components

       2. Produce ____________________ fluid, a lubricant