Integumentary System

Question 1

What is the epithelial type of the epidermis?

Answer 1

Stratified Squamous Keratinized Epithelium

Question 2

What four types of cells are there in the epidermis?

Answer 2

Keratinocyte
Langerhans cells
Merkel Cells
Melanocytes

Question 3

What forms the major distinction between thick

skin and thin skin?

Answer 3

Epidermis

Question 4

From the dermis, the epidermis consists of four layers of
keratinocytes (or five layers in thick skin)
What are there names?

Answer 4

FROM DEEP TO SUPERFICIAL
Stratum Basale
Stratum Spinosum
Stratum Granulosum
Stratum Lucidum (ONLY IN THICK SKIN)
Stratum Corneum

Question 5

What are the characteristics of Stratum Basale?

Answer 5

Single cuboidal or low columnar cells
Deepest layer
Replaced within 15-30 days
Keratinocytes, Merkel cells, and Melanocytes
They have tonofilaments

Question 6

What are the characteristics of Stratum Spinosum?

Answer 6

Several layers of keratinocytes joined by desmosomes
Langerhans Cells also present
Contain mature keratinocyte called Prickle Cells
Melanin is engulfed by these cells
They have keratin filaments

Question 7

Describe the characteristics of Stratum Granulosum.

Answer 7

Keratinocytes are flattened
3-5 layers of keratinocytes
Keratohylin granules (keratinized)
Lamellar granules (produce lipids that prevent dehydration and desquamation)

Question 8

What are the characteristics of Stratum Lucidum?

Answer 8

Only present in thick skin
2-3 layers of dead cells
Anucleate cells
Cytoplasm filled with keratin filaments

Question 9

Describe the characteristics of Stratum Corneum?

Answer 9

15-20 layers of dead cells
Keratin filled keratinocytes
Flattened cells with thick cell membrane called Squames
Desquamation occurs
The superficial layer

Question 10

Stratum Germinativum is another name for?

Answer 10

Stratum Basale

Question 11

What is the name of Antigen-presenting cell in the skin?

Answer 11

Langerhans cells

Question 12

What are the characteristics of Langerhans Cells?

Answer 12

Immune cells, large cell bodies with dendritic processes and nucleus is indented.
They are found in Stratum spinosum

Question 13

What are the characteristics of melanocytes?

Answer 13

Oval cells with long processes

PResent in Stratum basale and stratum spinosum

Question 14

What are the characteristics of keratinocytes?

Answer 14

They are present in all layers
Deep down they are cuboidal and at the superficial part they are flattened and dead cells
They have keratin filaments arranged
They also secrete lamellar granules

Question 15

What are the characteristics of Merkel cells?

Answer 15

Basally located sensory neuroendocrine cells

Globular cells

Question 16

What is Dermis?

Answer 16

It is made of connective tissue
Connects the epidermis to the hypodermis
Contains blood vessels, appendages, lymphatics and nerves
It has two layers.

Question 17

Papillary layer characteristics

Answer 17

It has loose connective tissue
It has dermal papillae
Collagen I and III
Collagen VII connects the basal lamina
Subpapillary vascular plexus

Question 18

Reticular layer characteristics

Answer 18

It has dense irregular connective tissue surrounding hair follicles, sebaceous glands and sweat glands, nerves, and deep plexus of blood vessels extending into the subcutaneous layer.
Collagen I and elastin

Question 19

What is Hypodermis?

Answer 19

Composed of areolar and adipose connective
tissue
Binds the skin to the underlying structure
Also called Superficial Fascia

Question 20

What is hair?

Answer 20

Elongated keratin structures (keratinocytes) derived from the invaginations of the epidermis in the dermis.

Question 21

Hair is surrounded by the hair follicle. What is a hair follicle?

Answer 21

Epidermis (Epithelial tissue) and Dermis (connective tissue) sheath.

Question 22

What is dermal papilla?

Answer 22

A dermal papilla inserts into the base of the hair bulb and contains a capillary network required to sustain the hair follicle.

Question 23

Matrix is secreted by the keratinocytes in the hair bulb and the matrix then forms?

Answer 23

Cortex (Tightly packed keratinocytes with high keratin)

Medulla (Keratinocytes with a moderate amount of keratin) of the hair.

Question 24

Hair is separated by the connective tissue by?

Answer 24

Glassy membrane made of hyaline

Question 25

What is Anagen?

Answer 25

A generally long phase of mitotic activity and growth | Hair growth cycle

Question 26

What is Catagen?

Answer 26

A brief period of arrested growth and then regression | Hair growth cycle

Question 27

What is Telogen?

Answer 27

A long period of inactivity in which the hair maybe shed

Question 28

Hair bulb is surrounded by what?

Answer 28

External and Internal root sheath

Question 29

From where do the Hair progenitor cells at the beginning of the new anagen phase come from?

Answer 29

External Root sheath. | The stem cells produce matrix.

Question 30

What are Sebaceous glands?

Answer 30

They are simple branched acinar glands that secrete oil in the hair follicle. They are not present in palms, soles, and side of feet.

Question 31

What is a sweat gland?

Answer 31

The sweat gland is a simple coiled tubular gland It is of two types Eccrine and Apocrine

Question 32

What is the eccrine sweat gland?

Answer 32

Eccrine sweat gland secretes water, metabolic wastes, salt, antibodies, etc. The secretory portion is in the dermis or hypodermis.

Question 33

What is an apocrine sweat gland?

Answer 33

They are found in Armpits, areola of the breast, and anogenital areas Their secretions are more vicious than that of the eccrine glands They start secreting at puberty The secretory portion is in the dermis or hypodermis The ducts open into hair follicles

Question 34

Examples of modified sweat gland

Answer 34

``` Ceruminous gland (ear wax glands) Mammary glands ```