Integumentary system Part 1

Question 1

SKIN IS DIVIDED INTO 3 LAYERS. name those layers.

Answer 1

1. Epidermis
2. Dermis
3. Hypodermis/ Subcutic

Question 2

The largest organ in the human body

Answer 2

Skin

Question 3

Skin is divided into two categories based on the thickness of the epidermis
Name those two categories

Answer 3

Thin and Thick skin

Question 4

What does the thick skin compromised of?

Answer 4

Thicker keratin layer

Question 5

Where do you find the thick skin and thin skin

Answer 5

Thick: Soles of the feet
Palms of the hands
Thin: covers the rest of the body

Question 6

Name the layers of the thin and thick skin

Answer 6

Thick- stratum basal
Stratum spinosum
Stratum granulosum
Stratum lucidum
Stratum corneum

Thin- all of the above layers except Stratum lucidum

Question 7

Between thick and thin skin, which one has hair follicles which one does not have Hair follicles

Answer 7

1. Thin skin has hair follicles
2. Thick skin does not have hair follicles

Question 8

Functions of the skin

Answer 8

1. Protection
2. Moisture control
3. Metabolic
4. Immunological
5. Themoregulation
6. Sensory

Question 9

Characteristics of Epidermis

Answer 9

1. High proliferative stratified squamous epithelial layer
2. Produces non-living layer of keratin
3. Non- epithelial cells (langerhans cells, Melanocytes and Merkel cells)

Question 10

Characteristics of Dermis

Answer 10

Fibrous and fribroadipose tissue layer that supports epidermis
Consists of blood vessels nerve and sensory receptors
.Responsible for tone and texture of skin
Connective tissue layer
Has 2 layers

Question 11

Hypodermic characteristics

Answer 11

Contain adipose tissue with supporting fibrous bands called septa
Contain large vessels

Question 12

Stratum Basale
1. Name the cells that make Stratum basala
2. Name the junction and the role
3. Stratum basale is highly mitotic and contains which cells, and what does this cells do
4. Specialized cells and the function
5. The basal cells form
6. Superficial progenitor basal cells mature

Answer 12

1. Cuboidal or columnar cells which rest on the basement membrane
2. Dermo-epidermal junction that binds the epidermis to the dermis
3. Progenitor cells that gives rise to the other layers of the epidermis
4. Melanocytes which is responsible for melanin production
5. The basal cells form an irregular basal surface and have an indented cell membrane with hemidesmosomes
6. Matures into cells of the stratum spinosum

Question 13

Stratum spinosum
1. Layers of spinosum
2. Explain the organelles
3. Other name?
4. Specialized cells
5. Keratinocytes matures into?

Answer 13

1. Multiple layers of polyhedral shaped keratinocytes
2. Round shaped nuclei, prominent nucleoli and cytoplasm
3. Prickle cell layer
4. Keratinocytes which is actively synthesize keratin
5. Matures stratum granulousm

Question 14

Stratum granulosum
1. Characteristics of cells
2. This cells undergoes which processes, and explain

Answer 14

1. 1-5 layers of flattened cells
2. Keratinization, filling cytoplasm with basophilic keratohyaline granules

Question 15

Stratum lucidum
1. Characteristics

Answer 15

Found only in the thick skin
Very thin single layer of translucent flattened cells which lack nuclei and organelles and are packed with mostly keratin filaments

Question 16

Stratum corneum
1. Explain the cells that make up stratum corneum
2. Name the basket weave pattern that the cells form
3. This cells are continuously shed at the?
4. Characteristics of this cells based on water.

Answer 16

1. The cells progress toward the surface lose their nuclei and cytoplasm and become keratinised squamous epithelial cells which then comprises the surface coating of the stratum corneum
2. Orthokeratosis
3. Epidermal surface
4. Are water repellent since they are coated with lipid containing anti wetting agents that were synthesized during maturation in the granular layer.

Question 17

The intra-epidermal antigen presenting cells (Histocytes)

Answer 17

Langerhans cells

Question 18

Where do we find langerhans cells

Answer 18

Presents in all layers of epidermis but easily noticed in stratum spinosum

Question 19

When the langerhans cells are stimulated what they do

Answer 19

They migrate from the dermis and then ti lymphatic system

Question 20

Explain the organelles in langerhans cells

Answer 20

Irregularly lobulated nuclei and almost clear cytoplasm
The cytoplasm processes extend from the cells and insinuate between keratinocytes

Question 21

The cell of the epidermis with a rod-like structure with cross striations

Answer 21

Birbeck granules

Question 22

The cytoplasmic organelle of Langerhans cells

Answer 22

Birbeck granules

Question 23

one end of Birbeck granules what it does?

Answer 23

One end distends into a vesicle, resembles a tennis cricket.

Question 24

Cells that produce melanin

Answer 24

melanocytes

Question 25

function of melanin

Answer 25

skin and hair colour

Question 26

True or False based on melanocytes 1.The numbers of melanocytes do not really vary; however, these cells are more active in dark-skinned people. 2. Has several branched dendritic process (easily seen on H&E stain). 3. Rounded cell bodies with clear cytoplasm appearance

Answer 26

1.True 2. False 3. True

Question 27

Melanocytes antigens shows what?

Answer 27

Melanocyte antigen shows globular cell-bodies situated in the basal layer with branching dendritic processes, seen under an immunohistochemical stain.

Question 28

In which area do we find more melanocytes?

Answer 28

Usually presented as separated individual cells in the basal layer, numerous in areas that are exposed to light

Question 29

In which form are the sensory nerve ending in the skin?

Answer 29

Sensory nerve endings in the skin are in the form of free-nerve endings and specialised encapsulated nerve endings (with the capsules being Schwann cells)

Question 30

Is sensory nerve ending in the skin myelinated or unmyelinated?

Answer 30

The sensory nerve ending in the skin can either be myelinated or unmyelinated..

Question 31

Free nerve endings are responsible for what?

Answer 31

Mainly responsible for Pain and Itch sensations and detecting Temperature

Question 32

Where do we find free nerve endings?

Answer 32

Occupy the papillary dermis and associate with Merkel cells in the epidermis to act as a slow-adapting mechanoreceptor Ramify around hair follicles

Question 33

small, encapsulated receptors that are found in the papillary dermis of the fingertips, soles of the feet, eyelids, lips and genitalia.

Answer 33

Meissner corpuscles

Question 34

These are fast-adapting mechanoreceptors which detect changes in texture and vibration

Answer 34

Meissner corpuscles

Question 35

Explain the structure of Meissner corpuscles.

Answer 35

Meissner corpuscles are ovoid with a collagenous tissue capsule that surrounds a mass of plump oval cells arranged transversely.

Question 36

Large, encapsulated sensory receptors that are responsive to pressure, coarse touch and rapid vibration

Answer 36

Pacinian Corpuscles

Question 37

Where do we find Pacinian corpuscles?

Answer 37

Located in the deeper layers of the hypodermis, singularly or in small clusters, numerous in palms and soles

Question 38

What do Pacinian corpuscles have?

Answer 38

Have a delicate capsule that contains concentric lamellae of flattened cells separated by interstitial fluid spaces and collagen fibres

Question 39

Intra-epidermal touch receptors

Answer 39

Merkel cells

Question 40

What does the Merkel cells contain?

Answer 40

Contain neuro-endocrine type membrane-bound vesicles in cytoplasm

Question 41

Where do we find the Merkel cells

Answer 41

Particularly near junctions with myelinated nerve endings in the upper dermis

Question 42

True or False based on Merkel cells. 1. Not easily seen on H&E stain, immunohistochemical stain sometimes used 2. Rounded cell with pale-staining cytoplasm

Answer 42

1. True 2. True

Question 43

Where are each free nerve ending receptors found?

Answer 43

Meisnner- (papillary) epidermis Pacinian-hypodermis Merkel-(intra-epidermal) epidermis

Question 44

Types of dermis

Answer 44

Papillary Reticular

Question 45

What structure runs vertically from deep reticular dermis to fascial fibrous tissue that underlies subcutaneous

Answer 45

Fibrous septa