Skin

Question 1

Functions of Skin?

Answer 1

Protection against chemical, thermal, mechanical insults, bacterial and fungal invasion and desiccation.
Protects against UV light
Has metabolic functions and has thermoregulation

Question 2

What are the two layers of the skin?

Answer 2

Epidermis and Dermis

Question 3

What is below the dermis?

Answer 3

Hypodermis

Question 4

What is the epidermis composed of?

Answer 4

Keratinised stratified squamous epithelium

Question 5

What is the dermis composed of?

Answer 5

Layer of fibrocartillagenous and elastic connective tissue containing blood vessels, nerves and sensory receptors.

Question 6

What is another word for the hypodermis?

Answer 6

Subcutis

Question 7

What is the hypodermis composed of?

Answer 7

Adipose tissue

Question 8

What does the hypodermis represent in anatomy?

Answer 8

Superficial fascia

Question 9

What are the 4 layers of the epidermis?

Answer 9

Stratum basale, stratum spinosum, stratum granulosum and stratum corneum

Question 10

What is the stratum basale?

Answer 10

This sits on the basal lamina. Serves as the stem cells for the epidermis

Question 11

What is the stratum spinosum?

Answer 11

Gives the cells a prickly appearance. It is a division in the basal layer that displaces cells upwards into this layer.

Question 12

What is stratum granulosum?

Answer 12

Require keratohyalin granules that contain profilaggrin that promotes the aggregation of the intermediate filaments.
Produce lamellar bodies.

Question 13

What is the stratum corneum?

Answer 13

Composed of dead squamous cells packed with keratin in a specialised matrix. It is a water proof barrier

Question 14

There can be a 5th layer of the epidermis between?

Answer 14

The granulosum and the corneum. It is a thin layer called the stratum lucidum

Question 15

What are the majority of cells in the epidermis?

Answer 15

Keratinocytes

Question 16

What are the cell types in the epidermis?

Answer 16

Melanocytes, Langerhan cells and Merkel cells

Question 17

How do melanocytes appear?

Answer 17

Pale with prominent dark nuclei comprising on the basale layer

Question 18

What do the meloncyted produce?

Answer 18

A brown-black pigmented melanin responsible for skin colouration

Question 19

Melanin can be found in which two forms?

Answer 19

A red-yellow form called pheomelanin and a brown-black for called eumelanin.

Question 20

What are the Langerhans cells?

Answer 20

They are resident immune cells of the epidermis and act as an antigen presenting cells.

Question 21

How does the Langerhans cell appear?

Answer 21

Pale with irregular nuclei in the stratum spinosum

Question 22

Lnagerhans cells have a network of processes to increase?

Answer 22

Surface area

Question 23

What are Merkel cells?

Answer 23

They are touch receptors found in the basal layer of the epidermis.

Question 24

What are the two layers of the dermis?

Answer 24

Superficial layer is the papillary dermis and the deeper layer is the reticular dermis

Question 25

What are dermal papillae?

Answer 25

Project upwards in the dermis

Question 26

What are rite ridges?

Answer 26

Project downwards of the epidermis

Question 27

What connective tissue is in the reticular dermis layer?

Answer 27

Dense irregular connective tissue

Question 28

What are the structures that invaginate and grow downwards into the dermis and sometimes hypodermis?

Answer 28

Hair follicles, Sebaceous glands and sweat glands

Question 29

What are hair follicles?

Answer 29

Tubula structure extending down through the epidermis and dermis into the hypodermis.

Question 30

What is at the bottom end of a hair follicle?

Answer 30

Hair bulb

Question 31

What is at the bottom of a hair bulb?

Answer 31

Dermal hair papilla

Question 32

What is within the hair shaft?

Answer 32

Keratin

Question 33

What cells are found in the hair bulb?

Answer 33

Melanocytes

Question 34

What does sebaceous glands produce?

Answer 34

Sebum

Question 35

What is the function of sebum?

Answer 35

It is an oily picture that helps make the skin supple and water resistant

Question 36

In H&E stains, what is the appearance of sebaceous glands?

Answer 36

Clear with an obvious central nucleus

Question 37

What is the small band of smooth muscles within a hair follicle?

Answer 37

Arrector pilli muscle

Question 38

Where does the arrector pilli muscle receive innervation?

Answer 38

From the sympathetic nervous system

Question 39

What are the two types of sweat glands?

Answer 39

Eccrine and Apocrine

Question 40

Where are eccrine glands found?

Answer 40

Everywhere in the skin, located at the junction of the dermis and hypodermic with a duct

Question 41

What glands are in thick skin?

Answer 41

Eccrine glands

Question 42

What are the two compartments of a sweat gland?

Answer 42

Secretory segment (coiled tubular gland) and a duct segment (coiled but then straightens)

Question 43

What epithelium is the secretory segment of the sweat gland?

Answer 43

Pseudostratified

Question 44

What epithelium is the duct segment of the sweat glands?

Answer 44

Stratified cuboidal

Question 45

Where are apocrine glands found?

Answer 45

Axillae, the genitalia and areola of the nipple

Question 46

What does the apocrine produce?

Answer 46

A milky fluid

Question 47

Where does the apocrine ducts end?

Answer 47

On hair shafts like the ducts of the sebaceous glands

Question 48

What secretion do apocrine glands utilise?

Answer 48

Merocrine secretion

Question 49

Nails are made of?

Answer 49

Keratin

Question 50

What is beneath the distal nail?

Answer 50

Nail bed

Question 51

The skin contains what types of sensory receptors?

Answer 51

Free nerve endings and encapsulated nerve endings