Skin

Question 1

What are 7 functions of the skin?

Answer 1

1. Excretion via sweat
2. Physical protection
3. Water retention
4. Sensory information
5. Barrier against UV
6. Temperature regulation
7. Manufactures vitamin D

Question 2

What are the 2 layers of the skin?

Answer 2

1. Epidermis

2. Dermis

Question 3

What are the 2 types of skin?

Answer 3

1. Thick Skin

2. Thin Skin

Question 4

Where is thick skin found?

Answer 4

Palms of the hand and soles of the feet

Question 5

Besides thickness, what is the major difference between thick and thin skin?

Answer 5

Absence of hair follicles on thick skin

Question 6

What type of tissue is the epidermis?

Answer 6

Stratified squamous keratinising epithelium

Question 7

What are the 4 cell types present in the epidermis?

Answer 7

1. Keratinocytes
2. Melanocytes
3. Merkel Cells
4. Langerhans Cells

Question 8

What is the function of keratinocytes?

Answer 8

Produce keratin

Question 9

What is the function of keratin?

Answer 9

Helps with water retention and waterproofing of skin

Question 10

What is the function of melanocytes?

Answer 10

Synthesise pigment melanin

Question 11

What is the function of melanin?

Answer 11

Protect against UV

Question 12

Where are melanocytes found?

Answer 12

Basal layer of the epidermis

Question 13

Where is melanin stores?

Answer 13

Melanosomes

Question 14

What is the function of Langerhans cells?

Answer 14

Part of the immune system

Question 15

What is the function of Merkle cells?

Answer 15

Function as mechanoreceptors i.e. detect shape

Question 16

What are the 5 strata of the epidermis in ascending order?

Answer 16

1. Stratum Basale
2. Stratum Spinosum
3. Stratum Granulosum
4. Stratum Lucidum (Thick Skin only)
5. Stratum Corneum

Question 17

What cells are found in the stratum basale?

Answer 17

Single layer of cuboidal cells

Question 18

What binds stratum basale to the basal lamina and dermis?

Answer 18

Hemidesmosomes

Question 19

At what strata of the skin does active cell division take place?

Answer 19

Stratum basale

Question 20

What cells are found in the stratum spinosum?

Answer 20

2-8 layers of prickle cells

Question 21

What causes cells to have a prickle appearance in stratum spinosum?

Answer 21

Desmosomes hold cells together but the rest of the membrane contracts

Question 22

What cells are found in the stratum granulosum?

Answer 22

2-3 layers of squamous cells

Question 23

At what strata does the nucleus being to break down?

Answer 23

Stratum granulosum

Question 24

What cells are found in the stratum corneum?

Answer 24

Cells with no organelles composed almost entirely of keratin

Question 25

What is the function of the lamellar body?

Answer 25

Produce lipids which are secreted to waterproof skin

Question 26

What type of tissue is the dermis?

Answer 26

Dense Irregular Connective Tissue

Question 27

Name 5 elements contained within the dermis

Answer 27

1. Fibroblast 2. Collagen fibres 3. Elastic fibres 4. Nerve fibres 5. Blood and lymphatic vessels

Question 28

What are the 2 layers of the dermis?

Answer 28

1. Papillary | 2. Reticular

Question 29

What is the papillary layer of the dermis?

Answer 29

Superficial region which interdigitates with epidermal ridges

Question 30

What is the reticular layer of the dermis?

Answer 30

Deeper region which is attached to underlying hypodermis

Question 31

What is the function of collagen fibres in the dermis?

Answer 31

Provide high tensile strength

Question 32

What is the function of elastic fibres in the dermis?

Answer 32

Provide elasticity and recoil of skin

Question 33

What is the hypodermis?

Answer 33

Connective tissue layer immediately deep to skin

Question 34

Name 3 epidermal appendages

Answer 34

1. Sweat glands 2. Hair follicles 3. Sebaceous glands

Question 35

What are the 2 types of sweat gland?

Answer 35

1. Merocrine | 2. Apocrine

Question 36

What is the arrector pili muscle?

Answer 36

Muscle found at the base of hair follicle which allows it to stand

Question 37

What is the function of the sebaceous gland?

Answer 37

Secrete sebum onto hair follicle

Question 38

Name 3 functions of sebum

Answer 38

1. Soften and lubricate hair 2. Slow water loss 3. Bactericidal function

Question 39

What word best describes sebaceous glands with regards to their release of sebum

Answer 39

Holocrine