Integumentary System

Question 1

What are the functions of the integumentary system?

Answer 1

Protection, Temperature regulation (sweat) , Sensation and metabolism (vit D synthesis)

Question 2

Epidermis

Answer 2

superficial keratinized stratified squamous epithelium facing the exterior of the body

Question 3

Dermis

Answer 3

CT deep to the epidermis that provides structural support and a route for blood vessels that provide nutritional support to the epidermis. Two layers- Papillary layer and reticular layer

Question 4

Papillary layer of the dermis

Answer 4

most superficial layer of the dermis consists of areolar CT adjacent to the epidermis

Question 5

Reticular layer of the dermis

Answer 5

Dense irregular CT forming the majority of the dermis

Question 6

Hypodermis

Answer 6

layer of adipose CT deep to the dermis (aka superficial fascia or subcutaneous adipose tissue)

Question 7

What are the major cell types found in the epidermis?

Answer 7

Keratinocyte, Melanocyte, Langherhan’s cells and Merkel cells

Question 8

Keratinocyte

Answer 8

Most common cells in the epidermis, produce the fibrous intermediate filament protein keratin that provides strength to the epidermis and helps make a water-resistant barrier

Question 9

Melanocyte

Answer 9

Cells that produce a brown pigment called melanin that absorbs UV radiation to protect from the damaging effects of the sun

Question 10

Langherhan’s Cells

Answer 10

Type of leukocyte found in the epidermis where they can monitor the skin for infections

Question 11

Merkel Cells

Answer 11

Specialized neuroepithelial somatosensory receptor cells that detect changes in the shape of the skin that contribute to our sense of touch

Question 12

What are the five layers of the epidermis?

Answer 12

Stratum basale, Stratum spinosum, stratum granulosum, stratum lucidum, stratum corneum

Question 13

Stratum basale

Answer 13

basal layer, deepest layer of the epidermis forms firm attachments to the basal lamina, stem cells in this layer undergo rapid division to produce keratinocytes, melanocytes and merkel cells also found at the border

Question 14

Stratum spinosum

Answer 14

spiny layer, 8-10 layers of cells superficial to the stratum basale, keratinocytes in this layer contain a web-like system of intermediate filaments of the pre-keratin protein attached to desmosomes, melanin granules and langerhan’s cells are abundant in this layer

Question 15

Stratum granulosum

Answer 15

granular layer, 3-4 cells thick, contains keratinocytes that are becoming flattened and disintegrating their organelles, and preparing to go through programmed cell death as they excrete lipid granules, the cytoplasm fills with keratin and the cell becomes flat and the plasma membrane thickens

Question 16

Stratum lucidum

Answer 16

clear layer, thin layer only a few cells thick, does not stain when prepared for light microscopy giving it a clear appearance, superficial to the stratum granulosum and deep to the stratum corneum in thick skin, this layer is not present in thin skin covering most of the body

Question 17

Stratum corneum

Answer 17

horny layer, superficial layer of dead kertainocytes filled w keratin and surrounded by glycolipids filling the extracellular space to create a water resistant barrier, thickest layer of the epidermis (about 2/3 of the epidermis), cells are constantly being shed from this layer, dead keratinocytes stay attached to the epidermis for about 2 weeks before they are normally shed

Question 18

Melanin

Answer 18

produced by melanocytes. gives skin a brown color

Question 19

Hemoglobin

Answer 19

Red pigment found in erythroctyes, increased blood flow can turn skin red, binding of oxygen to hemoglobin effects color, bright red when saturated w oxygen, when it becomes deoxygenated it turns dark red and appears blue though the skin

Question 20

Cyanosis

Answer 20

Blue coloring of the skin that indicates a lack of oxygen as occurs when a person is suffocating

Question 21

Bilirubin

Answer 21

A breakdown product of hemoglobin

Question 22

Jaundice

Answer 22

A yellow pigmentation of the skin and whites of the eyes due to high bilirubin levels, may indicate impaired liver function

Question 23

Carotenosis

Answer 23

Gives skin an orange color

Question 24

Hair follicle

Answer 24

small accessory organs that produce hair, made of keratin

Question 25

Hair root

Answer 25

deep into the dermis, grows out of the hair follicle and becomes the hair shaft as it grows superficially out of the epidermis

Question 26

Hair bulb

Answer 26

large bulge in the region surrounding the deep end of the hair root, papilla at the base of the hair bulb contain blood vessels that provide nutrients to the growing epithelial cells hair follicle

Question 27

Arrector pili

Answer 27

smooth muscle that pulls on the hair follicle to make the hair stand out causing goosebumps

Question 28

Hair follicle receptor

Answer 28

Consists of specialized endings of neurons that detect movement of hair

Question 29

Functions of hair

Answer 29

Protection, sensory input, thermoregulation and communication

Question 30

Free nerve endings

Answer 30

extend through the dermis and epidermis contribute to the sense of pain

Question 31

Pacinian corpuscle

Answer 31

found deep in the reticular layer of the dermis, is another somatosensory receptor that contributes to the sense of touch by detecting deep pressure and vibration

Question 32

Meissner corpuscle

Answer 32

A somatosensory receptor common in the skin on tips of the fingers that are very sensitive to detect light touch, found in the superficial portion of the dermis in Dermal papillae where areolar CT forms the superficial layer of the dermis called the papillary layer

Question 33

Merkel Cells

Answer 33

Specialized sensory receptor cells found in the deepest layer of the epidermis that are sensitive to the movement of the epidermis

Question 34

Sebaceous glands

Answer 34

Produce an oily secretion that protects and lubricates the hair and skin, composed of stratified cubpidal epithelium that uses the holocrine secretion mode to produce oily sebum

Question 35

Sudoriferous (sweat) glands

Answer 35

Coiled tubular glands that consist of stratified cuboidal epithelium that produces watery merocrine secretion to cool the body

Question 36

Eccrine glands

Answer 36

All over the body, more in palmar and plantar regions

Question 37

Appocrine glands

Answer 37

Located in the axilla, groin, face and nipples, function at puberty made of stratified cuboidal epithelial tissue

Question 38

Nail

Answer 38

An accessory structure produced by modified epidermal tissue, functions in protection, scratching and grasping small objects