CHAPTER 6: INTEGUMENTARY SYSTEM OBJECTIVES:
1. Name the organs and functions of the integumentary system.
Organs
Skin
Functions
Protection
Hair follicles
Regulation of Body Temperature
Sweat Glands
Sensory Reception
Sebaceous Glands
Vitamin D Synthesis
Nails
Immunity
Blood Reservoir
excretion
2. Explain why the skin is called the cutaneous membrane.
ET = keratinized stratified squamous ET
CT – dense irregular CT
3. Name the layers of the skin, describe the structure (tissues) of each, and name a
general function of each.
Epidermis = keratinized stratified squamous ET = protection
Dermis = dense irregular CT = strengthens skin; LACT = nourishes ET; glands = secretion;
etc
4. List the four/five layers of the epidermis (from basement membrane up), and
explain the process of keratinization.
Stratum corneum is the outermost thick layer of dead cell full of keratin = 100%
keratinization
Stratum lucidum is in thick skin only and is above the stratum granulosum
Stratum granulosum is a few layers of squamous cells that contain granules of keratin
Stratum spinosum contains cells that have pushed toward to surface and have started to
accumulate keratin
Stratum basale is a healthy looking cuboidal layer on top of basement membrane =
healthy cells = 0% keratinization
Basement membrane
5.
Explain the protective role of keratin, and in turn, the epidermis.
Keratin protects from mechanical injury, water-loss, effects from harsh chemicals, and
against harmful pathogens that can cause disease.
6.
Name the pigment responsible for skin and hair color, and explain how people of
different races (i.e. and skin color) differ in regards to it, and the cell that
produces it. Melanin - melanocyte
7.
List some factors that promote the production of melanin (besides DNA).
Sunlight, UV rays, X-rays, some drugs
8.
Distinguish between the papillary layer and reticular layer of the dermis, and
locate the appropriate sensory receptor in each of these layers.
Papillary is top 20% of dermis beneath
Bottom 80% of dermis with DICT and more
basement membrane with LACT and it
forms finger-like projections.
Meissner’s Corpuscle
Pacinian Corpuscle
9.
Compare and contrast tactile (Meissner’s) and lamellated (Pacinian) corpuscles
in terms of their structure, function, and location.
Tactile Meissner’s Corpuscle
lamellated (Pacinian) corpuscles
Specialized end of a dendrite that
Specialized end of a dendrite that
resembles a Q-tip
resembles onion
Fine touch receptor
Pressure receptor
Located in dermal papillae
Located deep in dermis and into
subcutaneous layer
10.
Describe the structure and function of the subcutaneous layer.
The subcutaneous layer lies beneath the dermis (hypodermis) and is composed of
adipose tissue = energy store; protection; and cushioning
11.
Explain what is meant by the term epidermal derivative, and list four examples.
An epidermal derivative originated from the epidermis = epithelium.
The four examples are hair follicles, merocrine sweat glands, apocrine sweat glands,
sebaceous glands.
12.
Describe the general structure of a hair follicle and identify two other structures
that are usually associated with them.
Root is down deep in dermis, the follicle runs up toward the surface, the shaft is the
exposed potion of hair. They are composed of keratinized stratified squamous ET with
melanocytes.
13.
Distinguish between merocrine (eccrine) and apocrine sweat glands in terms of
structure, secretion content and odor, activation, and major body locations.
Merocrine (Eccrine) Sweat Glands
Apocrine Sweat Glands
Respond to an increase in body
Respond to stress
temperature
Secretion is watery with water, salts, and
Secretion is thicker than merocrine sweat
wastes (urea and uric acid)
due to cellular debris plus water, salts, and
wastes (urea and uric acid)
No odor
Secretion does have odor
Run from coil to surface
Empty into a hair follicle
Function throughout life
Function from puberty and then through
life
Are widely distributed but are abundant
Axillary and Inguinal region
on the forehead, neck m and back
14.
Name two modified apocrine glands of the skin.
Ceruminous glands in external ear = protective wax
Mammary glands of breasts = nourishing milk
15.
Describe the structure, function, secretion, and location of sebaceous glands.
Sebaceous glands are holocrine glands that produce sebum (oil). They surround hair
follicles and deposit the sebum into it. The sebum keeps skin and hair soft, pliable, and
waterproof.