Anatomy and phys chapter 5

Question 1

• Epidermis:

Answer 1

Superficial layer of epithelial
tissue. (5 layers or strata)
– Avascular
– Separated from dermis by
BASEMENT MEMBRANE

Question 2

Dermis:

Answer 2

Deep layer of connective
tissue.
– Structural strength (Dense
irregular connective tissue)

Question 3

Subcutaneous tissue:

Answer 3

Not part of skin (consist of fat)
– Loose connective tissue that
connects skin to underlying
structures

Question 4

Epidermal Strata

Answer 4

Stratum corneum, 
stratum lucidum
stratum granulosum
stratum spinosum
stratum basale

Question 5

Stratum corneum -

Answer 5

Most superficial and consists of cornified cells

Question 6

Stratum lucidum

Answer 6

• Thin, clear zone. Found only in palms and soles (thick skin)

Question 7

Stratum granulosum

Answer 7

• Contains keratohyalin. In superficial layers nucleus and other
  organelles degenerate and cell begins to die.

Question 8

• Stratum spinosum -

Answer 8

Limited cell division. Desmosomes. Lamellar bodies and additional
keratin fibers

Question 9

Stratum basale

Answer 9

Deepest portion of epidermis and single layer. High mitotic activity and
cells starts to become keratinized (keratin fiber).

Question 10

Epidermal Cells

Answer 10

Keratinocytes
Melanocyte
Langerhan’s cells:
Merkel’s cells

Question 11

• Desquamate

Answer 11

cells of the deeper layers undergo mitosis; as they move toward the surface,
older cells slough off.

Question 12

Keratinization:

Answer 12

– as cells move outward through the layers they fill with keratin, die, and serve
as a layer that resists abrasion and forms impermeability layer

Question 13

Keratinocytes:

Answer 13

most cells.

• Produce keratin for strength

Question 14

Melanocytes:

Answer 14

contribute to skin color.
• Melanin produced by these cells then transferred to keratinocytes.
• Same number of melanocytes in all people

Question 15

Sensory functions:

Answer 15

: pain, itch, tickle, temperature, touch, pressure, two-point discrimination.
• Meissner’s corpuscle, pacinian’s corpuscle, free nerve endings

Question 16

Meissner

Answer 16

corpuscle fine touch

Question 17

Pacinian corpuscle

Answer 17

responsible for deep pressure

Question 18

Two Layers of the Dermis

Answer 18

Papillary.

– Reticular

Question 19

Papillary

Answer 19

Superficial (outer) 1/5.
• Areolar with lots of elastic fibers.
• Dermal papillae, capillary beds. Fingerprints. Whorls of ridges.
• Touch receptors, free nerve endings sensing pain

Question 20

Reticular:

Answer 20

Deep (inner) 4/5.
• Dense irregular C.T. Collagen and elastic fibers.
• In the figure see: some adipose, hair follicles, nerves, oil glands, ducts of sweat glands, heat
sensors, Pacinian’s Corpuscle, & arrector pili

Question 21

• Determined by 3 factors:

Answer 21

1. pigments
2. blood circulating through the skin
   a. Cyanosis: blue color caused by decrease in blood oxygen content
3. thickness of stratum corneum

Question 22

Pigments

Answer 22

melanin

carotene

Question 23

Melanin:

Answer 23

provides for protection against UV light. Group of chemicals derived from a.a. tyrosine.
• Colored brown to black, may be yellowish or reddish

Question 24

Carotene

Answer 24

yellow pigment. From vegetables. Accumulates in stratum corneum, in adipose cells of
dermis, and in Subcutaneous tissue

Question 25

Albinism

Answer 25

deficiency or absence of pigment. Production determined by genetics, hormones, exposure to
light

Question 26

Thick skin

Answer 26

Has all 5 epithelial strata
– Found in areas subject to pressure or friction
– Palms of hands, soles of feet
– Fingerprints and footprints. Papillae of underlying dermis in parallel rows

Question 27

Thin skin

Answer 27

More flexible than thick skin
– Lack stratum lucidum
– Covers rest of body
– Hair grows here

Question 28

Callus

Answer 28

Increase in number of layers in stratum corneum. When this occurs over a
bony prominence, a corn forms.

Question 29

Sebaceous Glands

Answer 29

Oily secretion (sebum)
– Prevents drying and
may inhibit bacteria
– Most empty into hair
follicle
• Exceptions: lips,
meibomian glands of
eyelids, genitalia

Question 30

• Sebaceous Glands

Answer 30

Oily secretion (sebum)

Question 31

Physiology of the Integumentary System

protection:

Answer 31

1. Against abrasion, sloughing off of bacteria as desquamation
   occurs. (stratified squamous epithelium)
2. Against microorganisms and other foreign substances.
   Glandular secretions bacteriostatic and skin contains cells of
   the immune system (Langerhan’s cells).
3. Melanin against UV radiation.
4. Hair on head is insulator and protection against light, and
   from abrasion. Eyebrows keep sweat out of the eyes;
   eyelashes protect eyes from foreign objects. Hair in nose and
   ear against dust, bugs, etc.
5. Nails protect ends of digits, self defense.
6. Acts as barrier to diffusion of water (keratin)

Question 32

Classification (Depth) of Burns

• 1st degree:

Answer 32

damages only epidermis
– redness, slight swelling, pain
– heals within 2-3 days (usually no scar)
– includes sunburns or exposure to cold

Question 33

2nd degree:

Answer 33

– damages epidermis and upper dermis
– redness, swelling, pain, blisters
– heals in 2 weeks with some scarring

Question 34

• 3rd degree

Answer 34

destroys epidermis and dermis
– burned areas are cherry red to black
– nerve endings are destroyed (no pain)
– skin graft might be necessary

Question 35

Burn & SurfaceArea

Answer 35

The Rule of 9s:

Question 36

– Head (Front & Back)

Answer 36

9%

Question 37

torso

Answer 37

• Front =18% (9% upper / 9% lower)

* Back = 18% (9% upper / 9% lower)

Question 38

Upper limb

Answer 38

9% each

Question 39

– Lower limb =

Answer 39

18% each
• Front = 9%
• Back = 9%

Question 40

– Genitalia

Answer 40

1%

Question 41

Subcutaneous (fat) tissue

Answer 41

Hypodermis (Subcutaneous fat)
– Superficial fascia
energy source, insulation, padding

Question 42

Types of cells

Answer 42

Fibroblasts
– Adipose cells
– Macrophages