Unit 4: Integumentary system

Question 1

Three layers on the skin

Answer 1

Epidermis, Dermis, Hypodermis.

Question 2

outer most:
middle:
(superficial fascia-outside of muscle)- Deepest region

Answer 2

Epidermis,
Dermis,
Hypodermis.

Question 3

Functions of the skin

Answer 3

protection, body temperature regulation, Cutaneous sensation, metabolic function, blood reservoir, excretion

Question 4

protection

Answer 4

chemical, physical, and mechanical barrier

Question 5

Dilation

Answer 5

cooling via blood vessels

Question 6

Constriction

Answer 6

warming via blood vessels

Question 7

metabolic function

Answer 7

synthesis of vitamin D in dermal blood vessels

Question 8

Cutaneous sensation

Answer 8

exo-receptors sense touch and pain

Question 9

blood reservoir

Answer 9

Blood vessels store up to 25%of the body’s blood volume.

Question 10

Characterization of epidermis

Answer 10

composed of keratinized (hardened keratin protein) stratified squamous epithelium.

consists of 4 to 5 layers

Question 11

Cell types for protection
(epidermis layer)

Answer 11

Keratinocytes (structure), Melanocytes (coloring), Merkel (sense of touch), and Langerhans’ cells (immune)

Question 12

keratinocytes

Answer 12

produce fibrous protein keratin.
product from stressors
extremely insoluble in water and organic solvents
most abundant in picture.

Question 13

Melanocytes

Answer 13

produce (brown) melanin pigment
UV protection
(Attached to basement membrane)

Question 14

Merkel cells

Answer 14

touch receptors in association with nerve endings.
(basal layer/right above dermal layer)

Question 15

Langerhans cells

Answer 15

epidermal macrophages that help activate the immune system

Question 16

Two types of skin:

Answer 16

Thick: 5 layers
Thin: 4 layers

Question 17

Stratum basale baby layer (bottom)

Answer 17

Deepest layer, attached to the dermis
Skin grows out of this layer
Single row of keratinocytes
Rapid cell division (mitosis)

Question 18

Stratum Spinosum

Answer 18

Keratinocytes appear “spiny” almost dehydrated
5-7 layers
Had filaments
Cells start to stick together
Contain melanin and langerhans cells

Question 19

What are filaments

Answer 19

Stick out of the cells as they shrivel and this is what makes this layer appear spiny.

Question 20

Stratum granulosum

Answer 20

Forms ridged membrane too keep cells form collapsing
Thin layer 3-5 layers
Rectangle like keratinocytes
Cells start to die
Keratohyalin granules
Lamellated granules

Question 21

Keratohyalin granules

Answer 21

Give keratin hardening

Question 22

Lemellated granules

Answer 22

Water proofing glycolipid (repels water)

Question 23

Stratum Lucidum (clear layer)

Answer 23

Extra layer of protection
Kinda dead cells
Thin transparent bad superficial to stratum granulosum
A few rows of flat dead keratinocytes
ONLY PRESENT IN THICK SKIN

Question 24

Thick skin

Answer 24

Heal, plantar, palm surface

Question 25

Stratum corneum

Answer 25

Outer layer of keratinized cells (cornified) Accounts for 3/4 of the epidermal thickness DEAD DEAD 20-30 layers thick

Question 26

Functions of stratum corneum

Answer 26

Water proofing protection from abrasion and penetration Rendering the body relatively insensitive to biological, chemical and physical assaults

Question 27

Dermis

Answer 27

Second major skin region contain gin string flexible connective tissue (areolar etc) Semi fluid matrix heavily embedded with collagen Highly vascular and lots of nerve endings Fibroblasts macrophages, mast cells/white blood cells Composed of toe layers

Question 29

Stratum granulosum

Answer 29

Thin layer 3-5 cells Drastic changes In keratinocytes Cells start to die Keratohyalin and lamellated granuales accumulate

Question 30

Keratohyalin granules

Answer 30

Give rise to ketamine (hardening )

Question 31

Lamellated granules

Answer 31

Give rise to a water proofing glycolipids

Question 32

Stratum Lucidum

Answer 32

clear layer/extra layer of protection kinda dead, few rows of flat dead keratinocytes, only in thick skin

Question 33

Stratum Corneum

Answer 33

outermost layer of keratinized (cornified) cells accounts for 3/4 of the epidermal thickness 20-30 layers

Question 34

functions of Stratum Corneum

Answer 34

water proofing protection from abrasion and penetration rendering the body relatively insensitive to biological, chemical and physical

Question 35

Dermis

Answer 35

middle layer; contains connective tissue Loose connective (areolar). semi-fluid matrix heavily embedded with collagen (very strong). HIGHLY Vascular and nerve endings

Question 36

Cells in the Dermis

Answer 36

Fibroblasts macrophages occasionally mast/white blood cells

Question 37

2 layers of dermis

Answer 37

Papillary and Reticular

Question 38

Papillary layer

Answer 38

Areolar/loose connective tissue with collagen and elastic fibers Papillae in the superior surface

Question 39

What are dermal papillae

Answer 39

Contain capillary loops, meissner’s corpuscles and free never endings dermal papillae make up epidermal ridges = fingerprints

Question 40

Meissner's corpuscles

Answer 40

type of nerve ending responsible for light touch ex: fingertips and palms

Question 41

Reticular layer

Answer 41

80% of the thickness of skin collagen fibers in this layer add strength and resiliency to skin. Elastin fibers provide stretch-recoil properties.

Question 42

hypodermis

Answer 42

- subcutaneous layer/superficial facia -Adipose (fat tissue) and areolar connective connects dermis to underlying muscle -adipose absorbs shock and insulates against heat loss.

Question 43

3 pigments that make up skin color

Answer 43

- melanin -carotene -hemoglobin

Question 44

melanin

Answer 44

yellowish to reddish-brown to black pigment responsible for dark skin colors freckles and pigmented moles

Question 45

carotene

Answer 45

yellow to orange: most obvious in the palms and soles of feet

Question 46

hemoglobin

Answer 46

reddish pigment: pinkish hue of light skin

Question 47

skin appendages

Answer 47

from dermis and epidermis includes: Nails, hair, sweat/oil glands and hair follicles

Question 48

sweat glands

Answer 48

simple cuboidal: sudoriferous basically everywhere jobs: regulate temperature, release water, salt and nitrogenous bases.

Question 49

Sebaceous glands

Answer 49

Protect and lubricate, keep off microbes

Question 50

Hemostasis

Answer 50

Body’s response to losing blood and that the “wall” has been compromised.