The Integumentary System

Question 1

structure of skin - epidermis

Answer 1

superficial layer
no blood vessels or nerve endings
varies in density - thickest areas include palms and soles
no hair

Question 2

structure of skin - dermis

Answer 2

middle layer
contains collagen and connective tissue interlaced with elastic fibers
blood vessels, sensory nerve endings, sweat glands and ducts, sebaceous glands, hair and arrector pili muscles present

Question 3

structure of skin - subcutaneous/hypodermis

Answer 3

continuous layer of tissue composed of adipose and areolar tissues (collagen cells)
functions as insulator, energy store and shock absorbed

Question 4

application - 1st degree burns

Answer 4

only top layer (epidermis) damaged

symptoms include: pink to red skin colour, slight swelling, dry skin, tender to severe pain

Question 5

application - 2nd degree burns

Answer 5

top and middle layers (epidermis and dermis) damaged

symptoms include: mottled red skin colour, clear fluid in blisters, moist skin, severe to extreme pain

Question 6

application - 3rd degree burns

Answer 6

all 3 layers (epidermis, dermis, subcutaneous) damaged
symptoms include: pearly white, tan coloured or charred skin colour, blood vessels and bones may be visible, dry and leathery skin, little to no pain

Question 7

functions - protection

Answer 7

an intact barrier prevents against invasion by micro-organisms, dehydration, UV light, trauma and chemicals

chemical = skin secretions, melanin
mechanical = continuity of skin, hardness of keratin cells, waterproofing
melanocytes = cells protect body from radiation

Question 8

functions - absorption

Answer 8

limited absorption of drugs e.g. HRT and nicotine patches and some toxic chemicals e.g. mercury

Question 9

functions - sensation

Answer 9

sensory receptors are nerve endings in dermis to:

touch and pressure (mechanoreceptor);
temperature (thermoreceptor);
pain (nocioceptor)

Question 10

functions - body temperature

Answer 10

regulates and maintains body temperature -

vasodilation and vasoconstriction (to skin to reach cooler air or reduce heat loss via radiation)
sweat glands for secretion
piloerection (standing up of hairs to trap heat)

Question 11

functions - excretion

Answer 11

sodium chloride in sweat/urea/garlic/other spices

sweat (sudoriferous) glands:
apocrine = open to hair follicle
eccrine = open to skin

sebaceous (oil) glands: attach to hair

Question 12

functions - vitamin d

Answer 12

formation + roles;

calcium and phosphate in the formation/maintenance of bones
supports immune function
regulates insulin levels
CV health

Question 13

onych/o

Answer 13

nail e.g. onycholysis = loosening or separation of finger/toe nail from nail bed

Question 14

ungu/o

Answer 14

nail e.g. subungual = situated or occurring under a finger/toe nail

Question 15

pil/o

Answer 15

hair e.g. pilosebaceous = of or relating to hair and the sebaceous glands

Question 16

trich/o

Answer 16

hair e.g. trichotillomania = compulsive desire to pull out ones hair

Question 17

structure of hair

Answer 17

keratin filaments with a root and shaft, with an arrector pili muscle attached

the arrector pili muscle is a bundle of smooth muscle fibers that are attached to each hair follicle

Question 18

functions of hair

Answer 18

1. body temperature - piloerection to trap air and insulate body to warm / facilitates evaporation of sweat to cool
2. protection - against sunburn (scalp), debris + dust (eyelashes), foreign particles (nostrils)
3. sense organ - vestibular system in inner ear detects head movements

Question 19

structure and function of nails

Answer 19

structure - hard horny keratin plates that protect the tips of both the fingers and the toes

functions - prevent bone damage, grasp/dig/itch

Question 20

sweat (sudoiferous) glands - eccrine

Answer 20

most numerous
body temperature regulation
smaller
discharge directly onto the skin surface
mainly water and NaCl

Question 21

sweat (sudoiferous) glands - apocrine

Answer 21

found in armpits, scrotum, anus, labia
larger
ducts open into hair follicles
often acted upon by bacteria -> odur

Question 22

sweat (sudoiferous) glands - secretion section and excretory duct

Answer 22

secretory section (gland) = dermis, it is a portion of a sweat gland that is a twisted + coiled tube w/ opening at very top for production of sweat

excretory duct = moves from secretion portion, through dermis, into epidermis where it opens up at skin surface

Question 23

sebaceous (oil) glands - location and structure

Answer 23

location = glands found on the scalp, groin, face, axillae (absent from palms and soles)

structure = secretory epithelial cells

Question 24

sebaceous (oil) glands - function

Answer 24

1. secrete oily substance that has antimicrobial properties - sebum
2. keeps hair follicles soft and pliable
3. acts as fungicidal and bactericidal agent preventing infection
4. prevent the skin from drying out and cracking (acts as lubricant to prevent excess evaporation of water)

Question 25

maintaining a healthy integumentary system - strategies

Answer 25

• bathing every day, wash hands regularly with appropriate technique and hygiene
• eat a well balanced diet and drink plenty of water
• apply sunscreen before spending time outdoors (UV = damage)
• moisturize skin to maintain integrity
• avoid wearing things that are too tight on your body as irritation (damage to epidermis) may occur)
• examine entire body on regular bases looking for abnormalities e.g. moles/freckles

Question 26

acne

Answer 26

occurs in areas rich of sebaceous glands
hormone changes stimulates release of sebum, blocks hair follicles and becomes infected with bacteria, resulting in inflammation

Question 27

psoriasis

Answer 27

chronic, inflammatory skin disease (non-contagious)
controllable but not curable, signs inc. itchy red skin
produces thickened scaly skin, resulting from excessive proliferation of skin cells (immune system problem)