integument REMAKE

Question 1

what are the 2 layers of the integumentary system
what is not a layer ?

Answer 1

• dermis
• epidermis
• hypodermis is NOT a layer

Question 2

what are the 5 layers of the epidermis

Answer 2

Come Lets Get Sun Burn
- stratum corneum
- stratum lucdium
- Stratum granulosum
- Stratum Spinosum
- Stratum basale

Question 3

what are the charecteristics of the stratum corneum
What does it protect against?
(3)

Answer 3

• it is the most superficial layer
• 20-30 layers of dead anucleated keratinocytes
• protects against friction and water loss

Question 4

• what are the characteristics of the stratum lucdium (2)

Answer 4

• 2-3 layers of dead anucleate cells
• only in thick skin

Question 5

what are the characteristics of stratum granulosom

Answer 5

• 3-5 layers of keratinocytes with distinct
• distinct kerato-hyaline granules

Question 6

what are the characteristics of stratum spinosum

Answer 6

• several layers of keratinocytes joined by desmosomes
• langerhan cells are present

Question 7

what are the characteristics of the stratum basale (5)

Answer 7

• deepest layer
• single layer of if cuboidal - low columnar cells
• in contact with the basement membrane
• mitosis occurs here to create new skin cells
• ## melanocytes and merkel cells are present

Question 8

what is the basal layer also called what is a special characteristic about this layer

Answer 8

• stratum germanitivum
• only layer that has dividing cells

Question 9

what type of cells make up the epidermis

Answer 9

• keratinized stratified squamous epithelium

Question 10

what layer of the epidermis are hemi - desmosomes closely associated with

Answer 10

• basal layer

Question 11

what is the difference between thick and thin skin

Answer 11

• thick - has no hair, no errector pilli, no sebaecous glands
• thin - no stratum lucidum

Question 12

what is the origin of the epidermis

Answer 12

surface ectoderm

Question 13

what is the origin of merkel cells and melanocytes

Answer 13

neural crest

Question 14

what is the origin of langerhan cells and what are their function

Answer 14

• monocytic origin ,
• macrophages of the epidermis ( immune system)

Question 15

what do merkel cells do?

Answer 15

light touch sensation

Question 16

what is the function of melanocytes

Answer 16

produce melanin to protect the dna in the nucleus from UV damage

Question 17

what is the function of the meisner corpuscle?

Answer 17

light touch and highly sensitive to sensation caused by low frequency vibrations
- tactile receptors

Question 18

what is the function of the pacinian corpuscle cells and where are they located

Answer 18

• sense deep pressure and high frequency vibrations
• found in the deep reticular dermis

Question 19

what are the layers of the dermis

Answer 19

-superficial papillary dermis
-deep reticular layer

Question 20

what are the characteristics of the papillary dermis
- what type of cell is found here

Answer 20

• loose CT
• meisner corpuscles are found here ( only found here)

Question 21

what are the characteristics of the reticular dermis
- what cells are found here

Answer 21

• dense irregular CT
• pacinian corpuscles are found here ( lamillae corpuscles)

Question 22

what are the sweat and sebaceous glands an extension of and where do they extend to?

Answer 22

they are externtions of the epidermis and extend to the reticular dermis

Question 23

what is the function of the epidermis

Answer 23

• water proof
• protects against mechanical stress

Question 24

what makes the epidermis water proof?

Answer 24

glycolipids and lipids

Question 25

what components of the epidermis protect against mechanical stress

Answer 25

the keratohyaline and tonofilaments

Question 26

what structures are localized in the basement membrane

Answer 26

hemidesmosomes

Question 27

what do the desmosomes do

Answer 27

they are in the lateral plasma membrane and connect cells btwn eachothers

Question 28

what do tight junctions do

Answer 28

separate the apical domain from the basal lateral domain

Question 29

what are the 2 different skin glands

Answer 29

- sweat glands - sebaceous glands

Question 30

through which mechanism do sebaceous glands secrete and why?

Answer 30

- holocrine secretion - they don't have myoepithelial cells to push the secretion through the ducts so they explode and have a layer of stem cells to regenerate the gland

Question 31

what type of sweat gland are there and through which mechanisms do they secrete

Answer 31

- eccrine >> merocrine secretion - apocrine >> apocrine secretion

Question 32

what allows the sweat grands to secrete?

Answer 32

- myopepithelial cells- push out the secretion

Question 33

what organ does not have myoepithelial cells

Answer 33

pancreas

Question 34

where are sabecous glands found in the body and what allows them to secrete sebum here?

Answer 34

they are found in the hair and errector pilli pushes the sebum upwards

Question 35

what type of muscle is found in errector pilli

Answer 35

smooth muscle

Question 36

what layers of the integument is vascularized what is not?

Answer 36

- dermis and hypodermis - NOT epidermis

Question 37

where are the 2 capillary plexuses

Answer 37

- papillary dermis - reticular dermis

Question 38

is there a possibility to shut off the penetration of blood to the papillary dermis ? if so, how?

Answer 38

yes, through the arteriole-venous anastomosis/ areteriole-venous shunt

Question 39

how are arteriole-venous shunts established

Answer 39

- blood goes directly from the artery to the vein and bypasses the papillary cappilaries

Question 40

where are arteriole venous shunts present

Answer 40

ONLY in the reticular dermis NOT in the papillary or hypodermis

Question 41

what layer of the epidermis do cancers arrise

Answer 41

basal layer

Question 42

what disease is caused T-lymphocyte autoimmune disease

Answer 42

psoriasis

Question 43

what vitamin does the skin make

Answer 43

vitamin D3 in the dermis under the influence of UV