Skin

Question 1

What Is The Epidermis?

Answer 1

Superficial layer composed of stratified squamous epithelium.

Question 2

What Is The Dermis?

Answer 2

Deep layer composed of connective pūtautau and containing blood vessels, lymph vessels and nerves.

Question 3

What’s In The Skin Appendages?

Answer 3

Hair follicles & hair
Sweat glands
Oil (sebaceous) glands
Nails

Question 4

Which type of epidermal cell, is the most abundant type in the epidermis?

Answer 4

Melanocytes are dispersed only throughout the deepest layer of the epidermis.

Question 5

Keratinocytes Job?

Answer 5

Produce keratin, a fibrous protein which toughens the skin and makes it waterproof

Question 6

Where are Keratinocytes found?

Answer 6

Keratinocytes are found in ALL epidermal layers and are continuously generated and replaced.

Question 7

Where are Melanocytes found

Answer 7

Found in the stratum basale of the epidermis

Question 8

What’s The Job of The Melanocytes?

Answer 8

Produce melanin which is a pigment taken up by keratinocytes to provide them protection from UV rays

Question 9

Langerhans cells job

Answer 9

They ingest foreign material and activate the immune system as necessary.

Question 10

Where Are Merkel Cells/Disks Found?

Answer 10

These are specialized cells found occasionally in the stratum basale.

Question 11

What Do Merkel Cells/Disks Do?

Answer 11

They respond to light touch and are associated with sensory nerve endings within the dermis below

Question 12

What is the epidermal layer found on the thickest skin (eg hands and soles of feet) ?

Answer 12

Stratum lucidum

In the thickest skin, found on the palms of the hands and soles of the feet, there is a fifth epidermal layer called the stratum lucidum- found between the stratum granulosum and stratum corneum.

Question 13

What Are The Dermal Papillae?

Answer 13

The dermal papillae are extensions of kiriwai that push up against the stratum basale of te kiritai, causing epidermal ridges which fit in the ‘dips’ between the dermal papillae; therefore the epidermis and dermis meet along a continuously undulating edge.

Question 14

What Are Dermal Ridges?

Answer 14

The dermal ridges are large mounds of dermal tissue in the fingertips which cause large undulations in the entire epidermis, creating the fingerprints that are typically (though not always) unique to each individual.

Question 15

Function of Nails ?

Answer 15

Nails are believed to function as ‘tools’ that aid in picking things up and scratching an itch.

Question 16

Sebaceous (Oil) Glands what are they ?

Answer 16

Sebaceous (oil) glands, the body’s only type of holocrine gland, are distributed throughout te tinana (except in the thickest skin) as outgrowths from hair follicles (see image above). These glands produce and secrete sebum which:
softens & lubricates hair and skin
slows water loss from te kiri
kills some bacteria

Question 17

Where Are Sweat Glands Found?

Answer 17

Found throughout nearly the entire skin (except the nipples and parts of the external genitalia).

Question 18

What are the 2 types of sweat glands that secrete sweat?

Answer 18

Apocrine sweat glands
Eccrine Sweat Glands

Question 19

What are the functions of the skin?

Answer 19

Protection
Blood reservoir
Vitamin D metabolism
Secretion of sweat & oil
Excretion of wastes & excess water & electrolytes (via sweat)
Sensory reception
Thermoregulation

Question 20

In what strata of the epidermis do melanocytes reside?

Answer 20

Stratum basale

Question 21

What is the function of Langerhan’s (dendritic) cells

Answer 21

To Provide immune protection Langerhan’s/dendritic cells are an immune based cell that can digest and remove microorganisms or foreign substances from the skin.

Question 22

What is the most superficial (outermost) layer?

Answer 22

Stratum Corneum

Question 23

What is the deepest layer?

Answer 23

Stratum Basale

Question 24

What are dermal papillae?

Answer 24

Mounds of dermal tissue that push up against the epidermis. The dermal papillae create an undulating border between the dermis & epidermis as they push up against the deeper layers of the epidermis.

Question 25

What is The reticular layer of the dermis is composed of?

Answer 25

Dense Irregular Connective Tissue

The deeper layer of the dermis- the reticular layer- is composed mostly of dense irregular CT which is rich in collagen fibers.

Question 26

What are dermal ridges?

Answer 26

Large mounds of dermal tissue which form the fingerprints